Hawkeye Coolant
09 February 2011, 04:14 PM
#31
Subaru HGs have been used on many high power builds - its the std head clamping and the affect of heat cycling that may be more to blame on the rash of 2006/07 HG problems.
Once the heads start to move then the HG starts flapping and the sealant comes away. This can be a slow process and maybe why some failures are difficult to spot in their infancy.
My Hg failure took over 10,000 miles to fully develop - but there never was any bad oil consumption issues.
Once the heads start to move then the HG starts flapping and the sealant comes away. This can be a slow process and maybe why some failures are difficult to spot in their infancy.
My Hg failure took over 10,000 miles to fully develop - but there never was any bad oil consumption issues.
10 February 2011, 12:29 AM
#32
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I'm no expert by a long way. All I know is he had the same symptoms as Mav and me.
I wasn't saying the oil loss was due to headgaskets. I meant that if he's consuming oil he might aswell get the pistons done at the same time.
I didn't and now they need doing! Which has cost me loads more money I wouldn't have had to spend if I did it right first time!
I know one thing for sure. Cosworth HG's can't be any worse than the Subaru ones!
I wasn't saying the oil loss was due to headgaskets. I meant that if he's consuming oil he might aswell get the pistons done at the same time.
I didn't and now they need doing! Which has cost me loads more money I wouldn't have had to spend if I did it right first time!
I know one thing for sure. Cosworth HG's can't be any worse than the Subaru ones!
07 March 2011, 01:09 PM
#33
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Update - After filling the expansion tank up with water it went over a week, including some longish journeys, with no problems whatsoever, including sitting in a 45 minute traffic jam, until I had stopped to fill with petrol after a 120 mile journey home - late no traffic - and when I went to pull away the temp gauge thought it was the new replacement for the Space Shuttle and headed skywards again and it took 4 stops to travel the 3 or so miles home.
Took it to local dealer who checked it over including pressure test and radiator out and could find no problem although, thinking about it, I'm not sure they did a compression test.
So now I need to keep one eye on the temp gauge, one eye on the speedo, one eye looking for speed camers and one on the road
Took it to local dealer who checked it over including pressure test and radiator out and could find no problem although, thinking about it, I'm not sure they did a compression test.
So now I need to keep one eye on the temp gauge, one eye on the speedo, one eye looking for speed camers and one on the road
However, longish trip back from Weymouth on Thursday and after a while it started misbehaving again with the temp gauge rising and falling like a fiddler’s elbow. Something I did notice, which is totally conflicting with my understanding, is that when the gauge was rising if I either booted it or dropped a gear whilst maintaining speed (ie increase in engine revs) the gauge generally stopped rising and started dropping back towards normal. If this was normal overheating I would have thought the extra load would increase the overheating problem.
So now I’m thinking sticking thermostat although that doesn’t explain the gunge in the expansion tank.
Last edited by GeeDee; 09 March 2011 at 07:42 AM.
21 April 2011, 06:10 PM
#34
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Final update - I hope!
Changed the thermostat - no difference.
Just driven car back 100 miles from API with new headgaskets (and new turbo and new cam belt and new forged pistons and new clutch and clean injectors and new BC suspension and new MOT and empty bank account - phew!) and can confirm my problems were as a result of two small HG leaks between cylinder and water jacket.
Still can't understand oily gunge in expansion tank nor small black bits of rubbery like material floating in coolant and can only assume the random overheating was due to gases getting into the cooling system from the cylinders and causing air locks.
Lets hope this episode is now well behind me and serves as future advice for others.
Changed the thermostat - no difference.
Just driven car back 100 miles from API with new headgaskets (and new turbo and new cam belt and new forged pistons and new clutch and clean injectors and new BC suspension and new MOT and empty bank account - phew!) and can confirm my problems were as a result of two small HG leaks between cylinder and water jacket.
Still can't understand oily gunge in expansion tank nor small black bits of rubbery like material floating in coolant and can only assume the random overheating was due to gases getting into the cooling system from the cylinders and causing air locks.
Lets hope this episode is now well behind me and serves as future advice for others.
Last edited by GeeDee; 22 April 2011 at 04:50 PM.
21 April 2011, 06:58 PM
#36
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The gunk in the tank was oil. The bits would have been the bits of gasket. That's what I was told! Good luck, sounds like you have a beast there!
In the end I got rid of mine and bought an 08 Renault megane r26 f1 with manufacturers warranty.
I've never been happier. Saying that it's going in for a slight leak from the cam cover!
Can't anybody build anything right anymore!?!
In the end I got rid of mine and bought an 08 Renault megane r26 f1 with manufacturers warranty.
I've never been happier. Saying that it's going in for a slight leak from the cam cover!
Can't anybody build anything right anymore!?!
22 April 2011, 05:44 PM
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It was a steel gasket with no "bits" to come off and there was no apparent leak to an oil way.
Also, having changed the thermostat and cleaned out the expansion tank, the gunge never reappeared although some more black bits did appear.
Also, having changed the thermostat and cleaned out the expansion tank, the gunge never reappeared although some more black bits did appear.
22 April 2011, 09:35 PM
#38
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You have oil in your cylinders you know. Where the gasket makes contact is made from viton, a rubbery material. The gasket itself is obviously made of steel! 
You probably had no bits 'left' to come off, as they were all in your cooling system!
You probably had no bits 'left' to come off, as they were all in your cooling system!
Last edited by TheDuke; 22 April 2011 at 09:37 PM.
23 April 2011, 11:57 AM
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Also, if the brand new gaskets David showed me had any coating on them it was clear, not black, but I'll bow to superior knowledge on this subject as things have moved on some since the days of rebuilding engines and changing head gaskets - I had never seen just a steel HG before and compared to the "fibre type" with metal rings around the cylinders was a little surprised
28 April 2011, 12:44 PM
#43
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Not that much oil I hope!! In fact my rings were in excellent condition - much better than expected but I didn't want to take the risk of the pistons breaking down so went for new ones.
Also, if the brand new gaskets David showed me had any coating on them it was clear, not black, but I'll bow to superior knowledge on this subject as things have moved on some since the days of rebuilding engines and changing head gaskets - I had never seen just a steel HG before and compared to the "fibre type" with metal rings around the cylinders was a little surprised
Also, if the brand new gaskets David showed me had any coating on them it was clear, not black, but I'll bow to superior knowledge on this subject as things have moved on some since the days of rebuilding engines and changing head gaskets - I had never seen just a steel HG before and compared to the "fibre type" with metal rings around the cylinders was a little surprised
Possibly particles of radiator hose innards that flaked off when the engine got hot.
No need to uprate the head studs on a standard build. Original bolts are fine in your situation.
Hows the suspension feel ??
Thanks for your custom - David
Last edited by APIDavid; 28 April 2011 at 12:46 PM.
28 April 2011, 07:49 PM
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Glad you got it all sorted. What a hassle and scare! Sounds like you have a rock solid engine now (I've heard very good things about API) and you can now mod your car over 350bhp safely if you wanted, now you have forged bits
Would uprated head studs prevent the gasket going again or is it just a case of fitting a better gasket like the new steel laminate one to stop this happening as our hawkeyes are prone to this issue?
Would uprated head studs prevent the gasket going again or is it just a case of fitting a better gasket like the new steel laminate one to stop this happening as our hawkeyes are prone to this issue?
28 April 2011, 11:11 PM
#45
This photo shows my 06 STi EJ257 opened up to show where the black coating lost around the hotter side of the cylinders. This happened on both sides of the block in the same places.
The black bits broke up and were found floating in the coolant.
03 May 2011, 10:39 AM
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There IS black coating on the HGs.
This photo shows my 06 STi EJ257 opened up to show where the black coating lost around the hotter side of the cylinders. This happened on both sides of the block in the same places.
The black bits broke up and were found floating in the coolant.
This photo shows my 06 STi EJ257 opened up to show where the black coating lost around the hotter side of the cylinders. This happened on both sides of the block in the same places.
The black bits broke up and were found floating in the coolant.
Apologies, it's the 2.0 that doesn't have the black bits.
So many engines, so many gaskets...................
David
08 September 2011, 06:23 PM
#47
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Final update - I hope!
Just driven car back 100 miles from API with new headgaskets (and new turbo and new cam belt and new forged pistons and new clutch and clean injectors and new BC suspension and new MOT and empty bank account - phew!) and can confirm my problems were as a result of two small HG leaks between cylinder and water jacket.
Just driven car back 100 miles from API with new headgaskets (and new turbo and new cam belt and new forged pistons and new clutch and clean injectors and new BC suspension and new MOT and empty bank account - phew!) and can confirm my problems were as a result of two small HG leaks between cylinder and water jacket.
After speaking with David, he agreed to get a whole unit in in advance so the fix could be turned around in a single day as I’m 100 miles away.
This was fixed yesterday and it feels great again. Also had a 20k service to make the journey worthwhile and so saved some money from local dealer even taking the petrol into account although not sure if a mobile camera got me on the M40 on the way home.
David, should you pick this up, and I’m sure you will, would you please remind me what air filter was put in please?
Big thanks to David and his crew who provided excellent service and advice as usual. Even got rabbiting about our road rallying exploits and, it seems, we were probably competing against each other at times.
Last edited by GeeDee; 08 September 2011 at 06:27 PM.
09 September 2011, 09:32 AM
#48
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Simota panel.
Thanks for your custom, glad to know that the suspension is back on top form again.
That's a bugger about the speed camera, Cross your fingers, most are switched out these days as they don't have the staff to work them. Digital ones still work though, IE the average speed thingy's. They link straight to the DVLA who send out the nicking automatically - or something like that.
regards David
Thanks for your custom, glad to know that the suspension is back on top form again.
That's a bugger about the speed camera, Cross your fingers, most are switched out these days as they don't have the staff to work them. Digital ones still work though, IE the average speed thingy's. They link straight to the DVLA who send out the nicking automatically - or something like that.
regards David
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