greasemonkey

How many Subarus have you done? It's getting a bit boring repeating this, but EJ20's aren't like all other engines. There's more than enough anecdotal evidence to suggest that the interruption in oil pressure caused by a "quick" oilchange can reduce the longevity of these engines - whether or not your own experience bears this out.

What advice would that be? IM advise dealers to both prefill the oil filters and establish oil pressure before firing.

Not really relevant is it? If you take the time to do the job properly, the chances of you needing a warranty claim in the first place are likely to reduce.

At the end of the day, none of us really care whether you go to these lengths or not. Fact remains that it's of the opinion of a number of people that taking a few extra minutes to carry out these steps could save a failed engine or few. Whether you choose to follow these steps is nobody's business but your own. As Les says, do what you want to do, but don't whinge and moan if your own engine lets go.

[Edited by greasemonkey - 9/6/2003 1:50:28 AM]

andypugh2000

Want to chage the oil on my scooby, after reading various posts on here what is the "definative" safe way of doing this as i hear stories about removing a plug and crank sensors etc, is this not as straight forward as an oil change on a ford fiesta????!!!

dhorwich

This is how greasemonkey's instructions went

Correct impreza engine oil change procedure

1) Warm engine

2) Drain old oil from sump

3) Remove old filter

4) Pre-fill new filter with fresh oil. Fill and keep filling until it won't take anymore.

5) Apply new filter

6) Apply new washer to sump plug and tighten

7) Fill engine oil filler to mid-way between two holes on the dipstick

8) Disconnect crank sensor

9) (Preferably) remove spark plugs

10) Dry crank engine at least until oil pressure light extinguishes - ideally for 20
seconds or so more.

11) Refit spark plugs

12) Refit crank sensor plug

13) Start engine, leave to idle for a good minute or so before driving for oil pressure to stabilise

14) Check sump plug and filter seal for adequate tightness/leaks

15) Go for slow drive until engine fully warmed

16) Top engine oil to upper hole

17) Check sump plug and filter seal for adequate tightness/leaks

Delboy2

Just done mine found step 4 took about half an hour and about 250mls of oil.

Bob Rawle

Step 4 is the one alot of people miss out on .... food for thought.

bob

greasemonkey

No Andy, it's not as straightforward as changing the oil on a Fiesta, as an Impreza's engine isn't as straightforward as a common or garden CVH

Thanks Dan for reposting the instructions, which, BTW, are a distillation of many peoples' experience, Bob, Pat and DavidAPI to name just a few.

mart360

i just drain & fit then fill with 10-40

nothing in my subaru owners manual about crank sensors and prefilling


Mart

Snoop Dogg

If people who know what they are talking about give directions then its best to follow them.

caz1562

The pre-filling is how a filter should be re-fitted. Its called common sense, costs nothing and simple to do.

mart360

If prefiling is common sense

i was wondering ...myself ( worked with cars for 20 years) my mate
(mechanic at main dealer) and his dad (cheif mechanical engineer)
Engines have never done this... and no probs with all the rebuilds we have done

so am i to ignore the advice of subaru who manufactured my car and whos manual i followed to change the oil???

which do you think would stand up in a warrranty claim

Mart

Leslie

Do your own thing Mart, but dont whinge if your big ends go!

Les

Delboy2

20 Seconds of oil starvation doesn't do the shells much good, the time taken to fill the filter from empty and prime the pump

rapac

I m still waiting for SOMEONE to post the official Subaru or dealers reply regarding the UK oil change procedure(prefill oil filter,plugs etc etc).
In the mean time I am following my Subaru manual instructions and so far so good with 162000kms on my97.
This is my offer:
If in OZ we take my wrx for a blast short or long and try to do a BIG END after an oil change(as per Subaru manual).
Next thing someone may suggest to pull the engine out for an oil change???
These are some of the web sites we have in OZ:
www.wrx.com.au/forum
www.wrx.net.au/forum
www.mrtrally.com.au/forum
Anyone who really believes that SAID oil procedure can save big end bearings failure can post it for discussion.
After all Australia has more than 16000 wrxs on the road.
PS.NT(40 C) has no speed limit and often wrxs will do 230k/h +

Cheers
Chris

mart360

Hmmm is this not a forum... are we not entitled to our own opinions??

I posted a reply to a question,,,based on what i have done for the

last 22 years.... fact: i have never prefilled an oil filter in my life..

I have never heard of this practice before... and as i stated ...my subaru owners manual makes no mention of prefiling the oil filter when carrying out an oil change...

I have noted from other posts that there are instances that shortly after an oil change has occured big end failure has occured..

as to what causes this... ?? at present the jurys out on that one..

I can see the reasoning behing disabling the ignition, but surely turning the engine over whether the ignition is conected or not is a moot point... you are still turning the engine over... and loading the bearings

i dont believe that the contents of a prefilled filter would go very far in such a short space of time?

If this was a common occurance i would have expexted IM to have recalled the affected vehicles , or issued a service bulletin.. i dont believe that has happened.
I accept that some of the owners who have owned scoobys for some time have found a method which works, and fair enough if people wish to follow there advice..

with regards to the "advice" its the page refering to changing the engine oil in my subaru owners handbook as issued by Subaru.


what happens if we get a post i prefilled the filter ... but my big ends have gone??

Mart

greasemonkey

Of course. Who said otherwise? As I keep saying, you, Rapac and whoever else can do what they like. However, as long as people keep asking what the "safest" method of changing the oil is, I daresay people will continue to suggest prefilling and dry cranking.

It ain't like it's just me, BTW. It may have been my post that Dan quoted, but that "list" was a distillation of a discussion involving Bob Rawle, David O'Brien, John Felstead, Pat Hebron and others. I also know that at least one of the UK's leading Subaru rally teams follows this method on all their cars - whether they be road, Group N, or WRC/Group A.

If you want to contend that a number of people with large amounts of Subaru experience either don't know what they're talking about, or are suggesting unnecessary levels of caution, you are more than entitled to do so, this being a forum and all.

The jury may be out, but there's more than enough smoke to suggest where the fire might be. If you can't suggest a more viable explanation though, your dismissal of the "pressure loss" theory rings more than a little hollow.

That's why it's suggested you remove the plugs. Even if you don't, there'll be a lot less load on the bearings if the engine is being turned on the starter without fuel or spark than there would be if it was firing.

If you don't believe this can be the problem, what other explanation can you offer for the increased frequency of engine failure shortly after an oil change?

That's not really practical if all the engines (with the possible exception of EJ207 with its modified crank and bearings) are theoretically susceptible, is it?

My local dealer told me several months ago that they had been instructed by IM to carry out this procedure. It was a moot point though as they already did it. There have also been a number of other people posting here saying their dealers did too.

Indeed. At no point have I or anyone else to my knowledge portrayed this method as a de facto "standard" and any other one as "wrong". What has been said is that this method is safer/less likely to lead to problems, which it is. At end of day, it's not going to cause any problems (bar possibly a DTC on some cars), and could prevent an expensive failure, so there's no good reason to suggest people not do it, yes?

Nobody has suggested that this method is a 100% cure-all for all big-end failures, so no doubt Scoobys will continue to blow up from time to time, whether this method is followed or not.

However, if there is a noticeable reduction in the number of post-oilchange failures as a result of people following this method, one exception probably won't break the rule...

MARK MORRIS

always done the fill the new filter bit on 12 years of opel manta ownership and my mums citroen ax, havnt changed the scoobs oil myself yet but planning to do an intermediate service on my sti7 myself next year, where is the crank sensor and how awkward is it to remove the plugs ?
mark

greasemonkey

Crank sensor is easy peasy, right at the top front of the block, immediately behind the timing marks on the cambelt cover, underneath the alternator.

Removing the plugs is nowhere near as easy as on an inline engine, to be sure, but it's far from impossible. To make access as easy as possible, removing the filter box, battery and washer tank is well worthwhile. Once you've got those out, a 3/8" ratchet, 14mm plug socket and 3" extension bar (and maybe a UJ) will get you in business.

andypugh2000

Cheers for the advice guts, just one more real dumb question, where is the crank sensor that i have to disconnect?? if anyone can post a picture or explain in detail that would be great.

cheers guys


andy

greasemonkey

Erm, look at my post immediately above Andy, everything you need is there!

Just press in the little detent on the CPS plug and disconnect it. Reconnect when you're done repriming the system.

andypugh2000

Doh!!! one of those days greasemonkey!!

Bob Rawle

Mart ... the words are ... "ostrich head sand in", the dealer manual doen't tell you to breath but you do don't you?

Some of us have done alot of work on this problem, how much have you done ?

cheers

bob

(only intersted in getting the problem solved)

mart360

Ok guys i give in find dark hole to hide myself in...

i wasnt trying to dispute what you were saying, merely posting what i have done over the years..

regarding the manual bit... I work very closly with most of the automotive manufacturing companys, and deal with similar types of issues on a daily basis,,, and the first question asked invariably is did you follow the correct procedures... and invariably they/ we will produce either a service manual or other documentation ... to validate or dispute the issues... what i was trying to put accross was if a.n. other states i carried out xxx when i did my oilchange and it varies from what the Manufacturer advises / reccomends,,, it can lead to claims being rejected...

One of the reasons dealers are now becoming reluctant or hesitant in accepting warranty claims is because previously the claim was passed back to the manufacturer.. and then onto the supplier of that part/ component.. and they picked up the costs... but it has become evident that some dealerships ( no specific models) were passing back either goodwill work or clearly non warrenty work...

because this is identified in various surveys.. JD power etc,, the motor manufactures have started looking at ways to improve things, and as a result have identified that this happens.. the result being that the cost is now picked up by the maindealer.

hence my comments... the last thing you want to do is give the dealers any more reasons to bounce claims

appologies if i have inadvertantly upset anyone..


my dark hole awaits

mart

Ive595

Read this thread with interest, and a question.....
Why do you need to remove the spark plugs? If it is to reduce compression when cranking the engine, then I understand, however if it is to stop detonation to allow oil pressure to increase then surely disconnecting the coil leads will do the same job.

Cheers

Ive

Bob Rawle

Mart ... no problem, appreciate your position, I, as others, know the issue that can be raised when dealer/Subaru proceedure3s are not followed but ... when it comes to oil change any engineer should akcnowledge that if you leave a filter mpty and then start the engine there will be a delay in pressure build up before the filter fills, so logically "fill the filter".

The big end syndrome has many schools of thought but ... one thing stands out is that service just b4 failure is common, those amongst us that run big power engines are particularly careful about this. So maybe, just maybe, you should take the "advice" back to your dealership and suggest its a good idea to fill the filter b4 assembly, especially as it takes 0.4 litres (up to) of oil to do this and when yu start the engine ITS NOT THERE until presure builds.

no offence meant

bob

mart360

Has anyone got any concrete figures of what the failure rate is??

if Subauru use an external supplier to manufacture the engines to there own (subaru) spec, i would guess that if there was a concern, they would be leaning pretty hard on the supplier to come up with a robust solution., however if its subaru themselves who manufacture / build the engines, well ?? the only way that might provide some openings for out of warranty vehicles concerns is through the new and ammended sale of goods act and or/ there is i believe a design limitation statue which may be applicable... i will dig through my files and let you know..

Mart

Welloilbeefhooked

iTrader: (3)

My word, its a bit hot in here!!!

My take on this is simple. It cant hurt to put oil in a filter (a very simple job) and then crank the engine to ensure correct lubrication (again, a very simple job).

So if you do this and its "possibly" over and above what Subaru suggest who cares about warranties and the like. You cant be voiding your warranty by doing this.


Just food for thought. I once fitted oil and filter on a so called bullet proof x-flow engine without priming. 2 miles down the road the big ends went. The carnk was only machined 2 months before and had been perfect before the oil change. The guy at the engine recon place said "You should have primed the filter", so now I do.

My run around "Cav GSI" is running 205,000 miles, of which I have done 150,000 of those. The engine is as sweet as a nut.


THIS IS DOWN TO PROPER CARE!!

greasemonkey

Exactly. Pre-filling and dry-cranking are simple, common sense measures that take virtually no time. There is no good reason not to do them.

MorayMackenzie

Heres another recent thread discussing this problem: http://bbs.22b.com/ubb/Forum8/HTML/000546.html

I know of one engine that had a big end failure shortly after a careful oilchange where the filter was primed and the crank position sensor was pulled to allow pressure priming on the starter. The plugs weren't pulled on the change though. So theres an exception to the "rule".

I am a little suprised that 3 engineers involved in the automotive buisiness for a large number of years hadn't come across the practice of priming the oilfilter. I'm sure I have read instructions to prime the filter actually written on OE replacement filters in the past.

greasemonkey

The "rule" also recommends plug removal as well Moray, so not quite an exception, although this is no comfort to the owner of the car concerned.

Every now and again a car will fail as a result of other issues, and a recent oil change will be coincidence more than anything else.

Jay m A

iTrader: (2)

Question.

Does the engine retain oil pressure when switched off? Or does it return to atmos when not running. I assume since oil drains into the sump it is open to atmoshere. So every time you restart a car, irrespective of an oil change theres always a certain time needed for the engine to build oil pressure.

Is there a reason that it takes longer for this pressure to build directly after an oil change? There must be otherwise you'd have to dry crank every time you want to start the car.

Thanks

Justin