Oil Change Questions
27 March 2010, 11:58 AM
#151
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That would be so funny, to see Toshi two times World Champion doing an oil change on a customers car
You could try Subaru Technica International... I actually have a few mates who work there, but I feel a bit stupid asking them such a question after the first reaction I got...
27 March 2010, 02:07 PM
#152
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Tanx for the picture Eggy. 
Hopper, re. Arai, why don't you put your journalist's hat on and ask the question? It'd be interesting to see if you got an answer out of him:
Toshihiro Arai
Arai Motor Sport Ltd
837-1 Shibamachi
Isesaki City
Gunma, Japan
Some do all of the above, most are probably too lazy Chris. However, Subaru UK dealers are not the "ones who build the engine". The engines are built by FHI or STi in Japan. And speaking of the ones who are too lazy (or dull)...
I'm sure Hopper and other victims of engine failure under similar circumstances will be pleased to hear of a Subaru UK or franchised dealer employee "laughing at this". Would you like to tell us where your brother works so we can phone the service manager up and ask them how they do it? Maybe we could ask for your bro by name?
You're not telling any of us on this thread anything we don't already know. You will never get loads of pressure in the system by cranking the engine on the starter, so I'm not sure what your bro thinks he's trying to prove there. The point is to purge air out of the oil system while the engine's not exposed to running pressures.
Really? Why?
Hopper, re. Arai, why don't you put your journalist's hat on and ask the question? It'd be interesting to see if you got an answer out of him:
Toshihiro Arai
Arai Motor Sport Ltd
837-1 Shibamachi
Isesaki City
Gunma, Japan
Some do all of the above, most are probably too lazy Chris. However, Subaru UK dealers are not the "ones who build the engine". The engines are built by FHI or STi in Japan. And speaking of the ones who are too lazy (or dull)...
I'm sure Hopper and other victims of engine failure under similar circumstances will be pleased to hear of a Subaru UK or franchised dealer employee "laughing at this". Would you like to tell us where your brother works so we can phone the service manager up and ask them how they do it? Maybe we could ask for your bro by name?
You're not telling any of us on this thread anything we don't already know. You will never get loads of pressure in the system by cranking the engine on the starter, so I'm not sure what your bro thinks he's trying to prove there. The point is to purge air out of the oil system while the engine's not exposed to running pressures.
Really? Why?
yer like i say simple ok. no one can def say yes or no so just do it 5 mins extra or like six mths over time for a poss new engine. i work as a parts man in a daihatsu IM garage. niks head thech he nows about this as been OLD skool so my dad he IS old skool. but they both said just do it for to be safe. am i correct that just turning the cracnk pully would lift the oil in to the filter and start to prime the system 1st?? as for filling the oil filter and just starting sure this would create two air locks??!!??
27 March 2010, 05:50 PM
#153
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While I did suggest it with tongue in cheek, the semi-serious point is that the bloke's an international ambassador for the Subaru and STi brands and thus it might be interesting to see his response to the situation Hopper found himself in.
Why would that be funny? Is something getting lost in translation here?
Theoretically, yes, but you'll be there for ages and will knacker yourself turning it over with a socket wrench, and in any case you won't be able to turn it over consistently at the same speed like the starter does.
Covered that earlier in the thread dude. Scroll up through my posts and you'll see it.
That would be so funny, to see Toshi two times World Champion doing an oil change on a customers car
as for filling the oil filter and just starting sure this would create two air locks??!!??
27 March 2010, 05:52 PM
#154
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[quote=Splitpin;9311393]Tanx for the picture Eggy.
Hopper, re. Arai, why don't you put your journalist's hat on and ask the question? It'd be interesting to see if you got an answer out of him:
Toshihiro Arai
Arai Motor Sport Ltd
837-1 Shibamachi
Isesaki City
Gunma, Japan
Splitpin,
I have written direct to Subaru HQ in Japan enclosing all previous correspondence between myself and IM, and asking for their reaction.
The last two letters to IM have gone unanswered.
They obviously feel they cannot say any more than they already have and probably hope I will just now fade away.
I will let you know if/when I get a response.
I don't think Toshi would have any opinions one way or other and it is Subaru that I need to speak.
It is interesting hearing all of these sceptics who "laugh" at the idea of having to go through the crank sensor process.
I would value their suggestions as to why they think my engine failed.
It was technicians like this who shrugged their shoulders, but admitted they had known of or rebuilt large numbers of engines due to the same problem.
Something is going wrong somewhere when a car with 36k miles and full Subaru history from new knocks its big-ends out 200 miles after a regular service.
Let's hear some theories from the doubters instead of laughter.
Hopper, re. Arai, why don't you put your journalist's hat on and ask the question? It'd be interesting to see if you got an answer out of him:
Toshihiro Arai
Arai Motor Sport Ltd
837-1 Shibamachi
Isesaki City
Gunma, Japan
Splitpin,
I have written direct to Subaru HQ in Japan enclosing all previous correspondence between myself and IM, and asking for their reaction.
The last two letters to IM have gone unanswered.
They obviously feel they cannot say any more than they already have and probably hope I will just now fade away.
I will let you know if/when I get a response.
I don't think Toshi would have any opinions one way or other and it is Subaru that I need to speak.
It is interesting hearing all of these sceptics who "laugh" at the idea of having to go through the crank sensor process.
I would value their suggestions as to why they think my engine failed.
It was technicians like this who shrugged their shoulders, but admitted they had known of or rebuilt large numbers of engines due to the same problem.
Something is going wrong somewhere when a car with 36k miles and full Subaru history from new knocks its big-ends out 200 miles after a regular service.
Let's hear some theories from the doubters instead of laughter.
30 March 2010, 01:50 PM
#155
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Ok, went and spoke to the mechanics at Arai Motorsports again today 
I was given three bits of good information.
1, The only reason that dry cranking with the CPS disconnected might have any effect, is if the owner of the car is using crap oil. High quality oils provide more than enough of an oil film all over the engine, for a long time... otherwise, you would have to do it everytime you start the engine.
2, When the oil goes from the oil pump, it first goes to the head, then wherever else it has to go. If there is any air in the system, it goes to the head, and out through the blowby pipe. Any air that could be in the crank or near the bearings, is nothing to worry about as the crank is low enough to the sump, not to worry about it.
3, There is a possibility of causing damage, WITH disconnecting the CPS. When you dry crank, the ecu forgets the position of the crank/cam. The instant you fire up, the CPS has to figure out what angle everything is at, so the first few combustion cycles could be causing det and knock etc.... until the sensor adjusts the fueling/spark to the cam/crank position.
They have never done it on any of their cars, and have never had any failures. Only one failure they told me about, was when an ecu when crazy, and caused the engine to blow... nothing to do with oil change.
As for reasons why your engine blew hopper, there is a plethora of reasons why... You may have been using crap oil, you may have thrashed your car before the service.... who knows.... we need details from you, on how you drove the car. I know that few people nowadays pay much attention to a "full subaru service history", as supposedley, the dealers don't have a clue what they are doing.
I was given three bits of good information.
1, The only reason that dry cranking with the CPS disconnected might have any effect, is if the owner of the car is using crap oil. High quality oils provide more than enough of an oil film all over the engine, for a long time... otherwise, you would have to do it everytime you start the engine.
2, When the oil goes from the oil pump, it first goes to the head, then wherever else it has to go. If there is any air in the system, it goes to the head, and out through the blowby pipe. Any air that could be in the crank or near the bearings, is nothing to worry about as the crank is low enough to the sump, not to worry about it.
3, There is a possibility of causing damage, WITH disconnecting the CPS. When you dry crank, the ecu forgets the position of the crank/cam. The instant you fire up, the CPS has to figure out what angle everything is at, so the first few combustion cycles could be causing det and knock etc.... until the sensor adjusts the fueling/spark to the cam/crank position.
They have never done it on any of their cars, and have never had any failures. Only one failure they told me about, was when an ecu when crazy, and caused the engine to blow... nothing to do with oil change.
As for reasons why your engine blew hopper, there is a plethora of reasons why... You may have been using crap oil, you may have thrashed your car before the service.... who knows.... we need details from you, on how you drove the car. I know that few people nowadays pay much attention to a "full subaru service history", as supposedley, the dealers don't have a clue what they are doing.
30 March 2010, 04:22 PM
#156
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Next time you speak to them, tell them they're full of cr*p.
No you weren't. You were given two bits of information that are largely b*ll*cks, along with a third that is complete and unadulterated ignorant bullsh*t. Well, it's either that or you are full of sh*t and haven't spoken to these people at all. Only you know how that works.
I'm not even going to bother with items 1 and 2 for now, as item 3 suggests that nothing you post from this point forward in the name of "Arai Motorsports" should be trusted.
That's cr*p. And therefore anyone saying so with a straight face is full of it.
The reason it's cr*p is because every time you start up, the Subaru ECUs (and no doubt the same with aftermarket ones) reacquire the position sensors and allow the engine to rotate and stabilise on the starter before initiating fuel and spark. Indeed, the ECU can't know into which cylinder and when to inject fuel and set fire to it until it knows whereabouts in the cycle the engine physically is.
As such, the engine is never started in a scenario where the ECU doesn't fully understand what the timing is, and thus there is no risk from damage in this way.
When you think about it, if what these muppets had told you was true, that would mean the engine was "at risk of damage" on its first start after removing the battery. It would also mean that the ECU would have to know, and retain in memory, the exact position the engine is in every time it stops, which it doesn't and can't do given the precision of the Subaru six point crank position wheel. If their line was correct it would mean the engine was at risk of "damage" every time it is started.
It's not true, and when you stop and think about it, it's not even logical. And believe me, on this one, I know what I'm talking about. If you really wanted me to, I could post up a disassembly of an ECU firmware showing exactly what it does when the engine is being started.
I'd already have done so if it wasn't for the fact that it'd be far too big to manageably post, and in any case without knowledge of the hardware architecture and low level programming languages you wouldn't have the foggiest idea what you were looking at. Still, if you don't believe me, it might be worth asking Steve Rally, Bob Rawle, JGM, Pat, Paul Zen or possibly Dynamix, as any or all of them should know how this works.
Without wanting to sound like I'm on your case too much, for the benefit of anyone else reading, there's no way to say this other than that you're quoting people who are full of it, or are making it up yourself and trying to name drop in an attempt to pick up a bit of credibility. Which is it?
No doubt David will be along when he has time to tell you why items 1 and 2 aren't exactly from the top drawer of the toolbox, although #1 has already been ably covered earlier in the thread.
I was given three bits of good information.
I'm not even going to bother with items 1 and 2 for now, as item 3 suggests that nothing you post from this point forward in the name of "Arai Motorsports" should be trusted.
3, There is a possibility of causing damage, WITH disconnecting the CPS. When you dry crank, the ecu forgets the position of the crank/cam. The instant you fire up, the CPS has to figure out what angle everything is at, so the first few combustion cycles could be causing det and knock etc.... until the sensor adjusts the fueling/spark to the cam/crank position.
The reason it's cr*p is because every time you start up, the Subaru ECUs (and no doubt the same with aftermarket ones) reacquire the position sensors and allow the engine to rotate and stabilise on the starter before initiating fuel and spark. Indeed, the ECU can't know into which cylinder and when to inject fuel and set fire to it until it knows whereabouts in the cycle the engine physically is.
As such, the engine is never started in a scenario where the ECU doesn't fully understand what the timing is, and thus there is no risk from damage in this way.
When you think about it, if what these muppets had told you was true, that would mean the engine was "at risk of damage" on its first start after removing the battery. It would also mean that the ECU would have to know, and retain in memory, the exact position the engine is in every time it stops, which it doesn't and can't do given the precision of the Subaru six point crank position wheel. If their line was correct it would mean the engine was at risk of "damage" every time it is started.
It's not true, and when you stop and think about it, it's not even logical. And believe me, on this one, I know what I'm talking about. If you really wanted me to, I could post up a disassembly of an ECU firmware showing exactly what it does when the engine is being started.
I'd already have done so if it wasn't for the fact that it'd be far too big to manageably post, and in any case without knowledge of the hardware architecture and low level programming languages you wouldn't have the foggiest idea what you were looking at. Still, if you don't believe me, it might be worth asking Steve Rally, Bob Rawle, JGM, Pat, Paul Zen or possibly Dynamix, as any or all of them should know how this works.
Without wanting to sound like I'm on your case too much, for the benefit of anyone else reading, there's no way to say this other than that you're quoting people who are full of it, or are making it up yourself and trying to name drop in an attempt to pick up a bit of credibility. Which is it?
No doubt David will be along when he has time to tell you why items 1 and 2 aren't exactly from the top drawer of the toolbox, although #1 has already been ably covered earlier in the thread.
Last edited by Splitpin; 30 March 2010 at 04:56 PM. Reason: Speling
30 March 2010, 04:52 PM
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I have nothing to add:- Splitpin has said it all.
That info is so far wrong, ALL OF IT - that it is impossible to believe that anyone at Arai's place would even think to utter it, unless you spoke to the secretary whilst she is doing her nails.
Go away djmisio85 we don't need your sort of crap here on Scoobynet.
David APi
Could djmisio be PS Lewis by any chance ???
That info is so far wrong, ALL OF IT - that it is impossible to believe that anyone at Arai's place would even think to utter it, unless you spoke to the secretary whilst she is doing her nails.
Go away djmisio85 we don't need your sort of crap here on Scoobynet.
David APi
Could djmisio be PS Lewis by any chance ???
Last edited by APIDavid; 30 March 2010 at 04:53 PM.
31 March 2010, 01:21 AM
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Oh - forgot to add to my previous post. If this bolx about "the first few combustion cycles could be causing det and knock etc" was in any way true, anyone who disconnects their crank position sensor and churns the engine over for a bit would notice their engine misfiring like a tw*t "until the sensor adjusts the fueling/spark to the cam/crank position" during the subsequent restart.
Hands up anyone here who's noticed their engine doing that after a CPS disconnect.
Really? For what it's worth I don't think DJMisio is Pete, the posting styles aren't similar enough. We'll see!
Hands up anyone here who's noticed their engine doing that after a CPS disconnect.
For what it's worth I don't think DJMisio is Pete, the posting styles aren't similar enough. We'll see!
31 March 2010, 03:43 AM
#162
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Ok, so maybe some of the smaller details got lost in translation, the whole discussion was in Japanese after all...
but again, those 3 main points simplified,
1,decent oil provides enough protection and a good enough film on the main parts - fact, you can't argue with that. Look into an engine, and you will see oil stuck to all the parts...
2, "if" any air gets into the system, its not enough to worry about it
3, I didnt say that disconnecting the crank sensor is a bad thing. I totally agree with the logic, of priming the system. I was told, that when the CPS is disconnected, usually nothing goes wrong, BUT, you have now admitted it aswell that something "could" happen, and you would get some misfires... but it usually doesnt. So this is like pot calling the kettle black. A usual oil change does not usually lead to massive engine failure.
The main thing is, the mechanics said, that dry cranking to prime the system, is NOT needed on a standard car. They change their oil the normal way every time, even on the PWRC car and no engine blows due to oil changes...
Im curious as to how many people have had a blown engine after an oil change? As with most things, especially on the internet, you only hear about the bad things that happen to people, and not thousands of people who haven't had a problem...
Also again to hopper, how was your car driven? What oil was used? etc etc
but again, those 3 main points simplified,
1,decent oil provides enough protection and a good enough film on the main parts - fact, you can't argue with that. Look into an engine, and you will see oil stuck to all the parts...
2, "if" any air gets into the system, its not enough to worry about it
3, I didnt say that disconnecting the crank sensor is a bad thing. I totally agree with the logic, of priming the system. I was told, that when the CPS is disconnected, usually nothing goes wrong, BUT, you have now admitted it aswell that something "could" happen, and you would get some misfires... but it usually doesnt. So this is like pot calling the kettle black. A usual oil change does not usually lead to massive engine failure.
The main thing is, the mechanics said, that dry cranking to prime the system, is NOT needed on a standard car. They change their oil the normal way every time, even on the PWRC car and no engine blows due to oil changes...
Im curious as to how many people have had a blown engine after an oil change? As with most things, especially on the internet, you only hear about the bad things that happen to people, and not thousands of people who haven't had a problem...
Also again to hopper, how was your car driven? What oil was used? etc etc
31 March 2010, 10:59 AM
#164
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but again, those 3 main points simplified,
1,decent oil provides enough protection and a good enough film on the main parts - fact, you can't argue with that. Look into an engine, and you will see oil stuck to all the parts...
1,decent oil provides enough protection and a good enough film on the main parts - fact, you can't argue with that. Look into an engine, and you will see oil stuck to all the parts...
A "film" is not "good enough", and if it was engines wouldn't have a high pressure directed lubrication system designed into them in the first place. If you want to know more about why this is the case, scroll up the thread.
2, "if" any air gets into the system, its not enough to worry about it
3, I didnt say that disconnecting the crank sensor is a bad thing.
BUT, you have now admitted it aswell that something "could" happen, and you would get some misfires... but it usually doesnt.
While the disassembly is too unwieldy to post, when I get round to putting it into a postable format I'll put up a datalog of the engine startup sequence that will clearly show you how the ECU acquires crank and cam position and then turns the engine at least two complete revolutions before enabling spark and fuel.
It is literally impossible for the explanation you gave previously to occur on a Subaru engine running standard engine management, and also, I would imagine, on pretty much every modern programmed ignition electronically controlled engine. Only an idiot would suggest otherwise, and thus it is difficult to believe that anyone who works on the technical side of these cars would tell you that. With the possible exception of the tea boy.
I don't have the slightest idea whether English is your first language or not but you're making a prat of yourself here and are polluting a legitimate technical discussion.
31 March 2010, 11:25 AM
#165
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As for reasons why your engine blew hopper, there is a plethora of reasons why... You may have been using crap oil, you may have thrashed your car before the service.... who knows.... we need details from you, on how you drove the car. I know that few people nowadays pay much attention to a "full subaru service history", as supposedley, the dealers don't have a clue what they are doing.[/QUOTE]
Also again to hopper, how was your car driven? What oil was used? etc etc[/QUOTE]
djmisio85
Without wishing to give creedence to these questionable "quotes" I will give the details you request as far as I know them.
I was told that the oil used in the engine was Shell Helix, previously I think it was Gemini though not sure of that. The Subaru dealer where the servicing was done used Shell oils anyway. I can only trust them that they used the proper stuff, but this seems a reasonable assumption.
When I asked them about the procedure there was mention only of priming the filter and nothing of disconnecting the CPS.
I won't be trusting the job to them anymore, needless to say.
Regarding how I drive the car, I am an experienced driver in my mid-fifties who drives quickly when able to.
It was just over 200 miles after the service that the big-ends went and yes, I had just extended the engine prior to the ticking noise first being apparent. (this rapidly turned to a knock).
Otherwise as stated previously in this and my other thread, the car was driven normally and serviced by the main dealer on the button from new.
I believed that a car treated like this should be reliable and that the engine should be good for considerably more than 36k miles before suffering big-end failure.
I am not a technical person, so I trust others more experienced than I to maintain the car - with regular oil level checks by me in between - so that I can use it in the manner that it was designed for when the opportunity arises.
I am not a traffic-light grand prix merchant if that is what you are getting at.
I note that you, like Subaru UK state that there are a number of reasons why my engine should fail. Perhaps with the information here you will be able to narrow things down for me.
IM (Subaru UK) have been unable or unwilling to offer further guidance, nor have they been able to recommend additional steps that I could take to prevent a future occurrence.
So, as stated previously on this and other threads my gods are David and Splitpin who have at least come up with a credible argument why it should have happened.
And for that reason I believe their account in the absence of any other reason why my engine failed, and since posting my original thread have learned that I am by no means alone.
Maybe I was unlucky. I am not alone in having this problem, but clearly there are a lot of people - Toshi Arai included apparently - who have sailed through Impreza ownership without difficulty, but I did what was advised of me for the good of my car and got stung. Big time.
Given the information available to me at the time I think I am entitled to feel let down by the system and the car.
Anyway, I keep reading about 'det' in this thread. What is that?
I am due to perform the 1,000 mile oil change post-engine rebuild tomorrow in a mechanic mate's garage on his ramp. I will be doing it to the letter of the recommended procedure given to me by David at API using the best oil and a genuine Subaru filter. Let's hope that is enough to prevent a further failure.
I am more confident this time.
Also again to hopper, how was your car driven? What oil was used? etc etc[/QUOTE]
djmisio85
Without wishing to give creedence to these questionable "quotes" I will give the details you request as far as I know them.
I was told that the oil used in the engine was Shell Helix, previously I think it was Gemini though not sure of that. The Subaru dealer where the servicing was done used Shell oils anyway. I can only trust them that they used the proper stuff, but this seems a reasonable assumption.
When I asked them about the procedure there was mention only of priming the filter and nothing of disconnecting the CPS.
I won't be trusting the job to them anymore, needless to say.
Regarding how I drive the car, I am an experienced driver in my mid-fifties who drives quickly when able to.
It was just over 200 miles after the service that the big-ends went and yes, I had just extended the engine prior to the ticking noise first being apparent. (this rapidly turned to a knock).
Otherwise as stated previously in this and my other thread, the car was driven normally and serviced by the main dealer on the button from new.
I believed that a car treated like this should be reliable and that the engine should be good for considerably more than 36k miles before suffering big-end failure.
I am not a technical person, so I trust others more experienced than I to maintain the car - with regular oil level checks by me in between - so that I can use it in the manner that it was designed for when the opportunity arises.
I am not a traffic-light grand prix merchant if that is what you are getting at.
I note that you, like Subaru UK state that there are a number of reasons why my engine should fail. Perhaps with the information here you will be able to narrow things down for me.
IM (Subaru UK) have been unable or unwilling to offer further guidance, nor have they been able to recommend additional steps that I could take to prevent a future occurrence.
So, as stated previously on this and other threads my gods are David and Splitpin who have at least come up with a credible argument why it should have happened.
And for that reason I believe their account in the absence of any other reason why my engine failed, and since posting my original thread have learned that I am by no means alone.
Maybe I was unlucky. I am not alone in having this problem, but clearly there are a lot of people - Toshi Arai included apparently - who have sailed through Impreza ownership without difficulty, but I did what was advised of me for the good of my car and got stung. Big time.
Given the information available to me at the time I think I am entitled to feel let down by the system and the car.
Anyway, I keep reading about 'det' in this thread. What is that?
I am due to perform the 1,000 mile oil change post-engine rebuild tomorrow in a mechanic mate's garage on his ramp. I will be doing it to the letter of the recommended procedure given to me by David at API using the best oil and a genuine Subaru filter. Let's hope that is enough to prevent a further failure.
I am more confident this time.
31 March 2010, 01:09 PM
#166
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Hopper, Det is short for detonation and can be created in many ways, for example;
Poor octane or old fuel.
High intake temperatures.
Excess or optimistic timing.
Oil consumption [ see 1 above ] weakening the octane rating of the fuel.
In fact anything that compromises the burn capability of the fuel.
Det shock loads the piston crown which is translated into energy going down the shaft of the con rod and overloading the upper bearing in the big end of the con rod.
If you take a set of big end bearings out of a set of turbo car rods, you can always tell the upper bearing, as it will have a bruise mark where it has absorbed the load. The lower shell does not take anything like as much load and remains evenly marked in a healthy engine.
That help??
David
Poor octane or old fuel.
High intake temperatures.
Excess or optimistic timing.
Oil consumption [ see 1 above ] weakening the octane rating of the fuel.
In fact anything that compromises the burn capability of the fuel.
Det shock loads the piston crown which is translated into energy going down the shaft of the con rod and overloading the upper bearing in the big end of the con rod.
If you take a set of big end bearings out of a set of turbo car rods, you can always tell the upper bearing, as it will have a bruise mark where it has absorbed the load. The lower shell does not take anything like as much load and remains evenly marked in a healthy engine.
That help??
David
31 March 2010, 03:33 PM
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While the disassembly is too unwieldy to post, when I get round to putting it into a postable format I'll put up a datalog of the engine startup sequence that will clearly show you how the ECU acquires crank and cam position and then turns the engine at least two complete revolutions before enabling spark and fuel.
I don't have the slightest idea whether English is your first language or not but you're making a prat of yourself here and are polluting a legitimate technical discussion.
I don't have the slightest idea whether English is your first language or not but you're making a prat of yourself here and are polluting a legitimate technical discussion.
And no, I'm not a troll, I just want to know more about this whole issue...
Now without you two getting too rowdy, I have a question in relation to the above quote.
When the the CPS acquires the information during the first two revolutions, that is also turning the oil pump and giving oil pressure without combustion forces right? (Similar to dry cranking )
Are these two revolutions not sufficient enough under normal circumstances?
31 March 2010, 07:42 PM
#168
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Thanks for that David.
I feel I have learned a lot recently!
BTW We tried disconnecting the battery and counting to 20, but still the engine light stayed on. In the end my mate connected up his SnapOn meter to the plug under the dashboard and when it showed up that the CPS had a 'fault' he was able to clear it and the light went out.
All is fine now.
I feel I have learned a lot recently!
BTW We tried disconnecting the battery and counting to 20, but still the engine light stayed on. In the end my mate connected up his SnapOn meter to the plug under the dashboard and when it showed up that the CPS had a 'fault' he was able to clear it and the light went out.
All is fine now.
Last edited by Hopper; 31 March 2010 at 07:44 PM.
01 April 2010, 04:44 PM
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When the the CPS acquires the information during the first two revolutions, that is also turning the oil pump and giving oil pressure without combustion forces right? (Similar to dry cranking )
Are these two revolutions not sufficient enough under normal circumstances?
However, two revolutions, as John has already explained, will in no way be enough to purge a few hundred cubic centimetres of air out.
01 April 2010, 07:13 PM
#171
Wow, a six page thread on oil change procedure.
Very simple, if you do not think it is advantageous to prefill the oil filter and crank the engine without starting it until oil pressure builds, you are under no obligation to follow this advice. Being cynical, the shorter your engine life the better for guys like David at API, Splitpin or me.
FWIW : My cars have switches to isolate the fuel pumps and the main reason for this is to additionally facilitate the pump running continuously so I can pump out the fuel tank when I wish.
To achieve oil pressure from an engine stood overnight takes about ten seconds of cranking. I will actually time it if I remember tomorrow.
I regularly crank to full oil pressure if the car has stood overnight, particularly when temperatures are very low or extended parked up periods, before activating the fuel pump and starting.
The reason I do this is simply that over an extended period, I have observed the engine noise, during and on start up. When prelubricating then starting the engine has less noise, absolutely no question of that.
Just another observation, on some marine deisle propulsion units, a lot of effort goes into prelubricating before start up.
Very simple, if you do not think it is advantageous to prefill the oil filter and crank the engine without starting it until oil pressure builds, you are under no obligation to follow this advice. Being cynical, the shorter your engine life the better for guys like David at API, Splitpin or me.
FWIW : My cars have switches to isolate the fuel pumps and the main reason for this is to additionally facilitate the pump running continuously so I can pump out the fuel tank when I wish.
To achieve oil pressure from an engine stood overnight takes about ten seconds of cranking. I will actually time it if I remember tomorrow.
I regularly crank to full oil pressure if the car has stood overnight, particularly when temperatures are very low or extended parked up periods, before activating the fuel pump and starting.
The reason I do this is simply that over an extended period, I have observed the engine noise, during and on start up. When prelubricating then starting the engine has less noise, absolutely no question of that.
Just another observation, on some marine deisle propulsion units, a lot of effort goes into prelubricating before start up.
01 April 2010, 08:42 PM
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Wow, a six page thread on oil change procedure.
Very simple, if you do not think it is advantageous to prefill the oil filter and crank the engine without starting it until oil pressure builds, you are under no obligation to follow this advice. Being cynical, the shorter your engine life the better for guys like David at API, Splitpin or me.
Very simple, if you do not think it is advantageous to prefill the oil filter and crank the engine without starting it until oil pressure builds, you are under no obligation to follow this advice. Being cynical, the shorter your engine life the better for guys like David at API, Splitpin or me.
FWIW : My cars have switches to isolate the fuel pumps... over an extended period, I have observed the engine noise, during and on start up. When prelubricating then starting the engine has less noise, absolutely no question of that.
And can't fault the isolate switch. My own's got a way of stopping injection and spark without having to disconnect anything. I've extended the pre-start crank delay a little as well, just as a bit of insurance.
02 April 2010, 12:24 AM
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I take it Harvey's method is running the power to the fuel pump to a switch on the dash?
02 April 2010, 12:56 AM
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The way I've done the start inhibit switch (and the only way to increase the automatic pre- start delay) is by customising the ECU firmware. However the only reason I've done it that way is because I've done a stack of other much cooler things to it, and as a result these extras became very simple to add.
You could achieve the same thing simply by cutting the wire from the crank position sensor in the ECU loom and soldering in a switch that you fit somewhere in the cabin. That way, flicking the switch off does exactly the same thing as physically unplugging the sensor, but you can do it all easily from the driver's seat.
If you hid the switch somewhere not immediately accessible, or disguised it as something else, it has the potential to become a passive anti-theft device too.
Without wanting to speak for him, if you got a single pole double throw switch with three positions (On-Off-On), and connected its middle pin to the wire going to the fuel pump, and then the outer two from the regular pump drive, and a permanent fused 12v source, when you have the switch in the centre you'll have pump inhibit. If you flick it one way you'll have regular ECU control and to the other, manual "on" for draining etc like Harvey's.
Again, where you site the switch is up to you. Hiding it has certain passive security benefits.
You could achieve the same thing simply by cutting the wire from the crank position sensor in the ECU loom and soldering in a switch that you fit somewhere in the cabin. That way, flicking the switch off does exactly the same thing as physically unplugging the sensor, but you can do it all easily from the driver's seat.
If you hid the switch somewhere not immediately accessible, or disguised it as something else, it has the potential to become a passive anti-theft device too.
I take it Harvey's method is running the power to the fuel pump to a switch on the dash?
Again, where you site the switch is up to you. Hiding it has certain passive security benefits.
02 April 2010, 04:35 AM
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Hopper:
PPP....did the dealer replace the fuel pump when they Prodrive tuned the car?
Standard fuel pump cannot live up to the pressure, leading to lean mixture and detonation at high revs. Moderate, you wouldn't necessarily hear it, and it would be worst when hitting the rev limiter...where the engine sounds and performs oddly anyway.
Perhaps this a new tack on IM.UK? If the car was running, or still is(!), a standard fuel pump, they should have replaced it during the PPP upgrade.
PPP....did the dealer replace the fuel pump when they Prodrive tuned the car?
Standard fuel pump cannot live up to the pressure, leading to lean mixture and detonation at high revs. Moderate, you wouldn't necessarily hear it, and it would be worst when hitting the rev limiter...where the engine sounds and performs oddly anyway.
Perhaps this a new tack on IM.UK? If the car was running, or still is(!), a standard fuel pump, they should have replaced it during the PPP upgrade.
02 April 2010, 03:40 PM
#176
Without wanting to speak for him, if you got a single pole double throw switch with three positions (On-Off-On), and connected its middle pin to the wire going to the fuel pump, and then the outer two from the regular pump drive, and a permanent fused 12v source, when you have the switch in the centre you'll have pump inhibit. If you flick it one way you'll have regular ECU control and to the other, manual "on" for draining etc like Harvey's.
Of course those of us with Simtec ECUs can vary the starting if we want through the ECU
Harvey, there are some on this thread who no amount of real world observation will convince. But, as you say, it's entirely up to them what they do.
You have attracted a disproportionate number of numpties to this thread. I do wonder why just like I wonder why there are so many corrupt numpties in Westminster. That too seems disproportionate.
Another one of life's little mysteries as David Attenborough would say.
Last edited by harvey; 02 April 2010 at 03:47 PM.
02 April 2010, 03:51 PM
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im confused now
harvey my car is a weekend car .. parked up for 5 days on the road and starts up first time everytime, are yous aying i should ideally crank it on starter build oil pressure again before starting it?
these cars seem soo much headache lol
harvey my car is a weekend car .. parked up for 5 days on the road and starts up first time everytime, are yous aying i should ideally crank it on starter build oil pressure again before starting it?
these cars seem soo much headache lol
02 April 2010, 04:31 PM
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I assume the Boxer engine has (effectively) a dry sump,if thats the case everytime the engine is stopped, as well as losing pressure instantly (same in all engine's, wet or dry sump)you will only be left with a micro-thin film of oil on the crank/bearings, as the majority of oil will drain out from the bearings (even in a wet sump only a small part of SOME of the bearings will be sat in an oil bath) exposing the crank to a "dry" atmosphere EVERY time the engine is stopped,so the theory you should disconnect the sensor on every oil change is a load of bollocks,coz that would mean every time your engine is stopped for a period of time (overnight for example) you should disconnecting said sensor before re-starting it.
Dry sumps have been in use for years on ultra highly tuned motor bikes (and other vehicles) with NO evidence of rapid (instant) engine failure.
I have no doubt engines have failed after having an oil change (by Scooby dealers) , but I also have no doubt engines have failed within 1 mile of leaving the factory.And not just Subaru either..
Dry sumps have been in use for years on ultra highly tuned motor bikes (and other vehicles) with NO evidence of rapid (instant) engine failure.
I have no doubt engines have failed after having an oil change (by Scooby dealers) , but I also have no doubt engines have failed within 1 mile of leaving the factory.And not just Subaru either..
