Oil on top of piston - Page 2 - GT-R Register - Official Nissan Skyline and GTR Owners Club forum

Phil69 · 28th July 2012, 10:27 PM

This might sound lame but, how do I do that? Not something I've tried before.

R32 Combat · 28th July 2012, 10:33 PM

You need an air compressor and a leakdown tester. It's a much better was of testing how well the combustion chamber is sealed. Google it.

Phil69 · 28th July 2012, 10:34 PM

Ahh right. I get it now. I assume it holds the pressure in so you can watch it over a period rather than the quick blast of pressure as you crank the engine for a compression test.
Thanks for your help!

R32 Combat · 28th July 2012, 10:38 PM

I hope you get it sorted.

DrGtr · 28th July 2012, 10:48 PM

just start with a check list of a couple of things, leak test , even though if you have a good symmetrical compression test i would just unbolt the turbo first and be sure that its not the seals , i dont have the experience but my opinion is that is the turbo.

Phil69 · 28th July 2012, 10:51 PM

I already removed the front turbo and there is oil coming through the exhaust port into the manifold so the oil is from before the turbo plus, as said before, the inlet pipes are clean and there is oil on the piston.

xxfr · 30th July 2012, 02:07 AM

Sometimes the oil in the cylinder above the piston tends to seal and hold pressure, enough to give false compression readings. Do the leak down test as that will give you a better result.

I have seen in big truck engines when rings give up and they start using oil like hell. The oil ends up in the cylinders from the bottom through around the rings and up. Put the same pistons back in with new rings and problem is solved.

bucharest · 12th August 2012, 07:10 AM

i think maybe your turbo let go and the wet piston may be a different issue. one thats not such a big deal. how much oil on top we talkin bout tho ? and did plug 2 actually have oil on and look different than the rest ? and plus 1 for a leakdown test.

Mark@Abbey M/S · 12th August 2012, 08:37 AM

Wet piston top as long as it isn't swimming in the liquid I wouldn't worry, when you run a car and turn it off and pull the spark plugs your see the top of the pistons still damp.

If you put #2 cylinder to TDC can you put a long screw driver down the plug hole and touch the fluid and then inspect it?

If you have neat oil in the down pipes and good compression's I would say you have a turbo failure.

It does all seem strange that the car was running lean before you have the failure thou as these 2 items aren't connectted at all.

Mark@Abbey M/S · 12th August 2012, 08:46 AM

Sorry just read the oil is coming down the exhaust port, no the turbo outlet.

Can you see where the oil is coming from? Is it coming down the exhaust valve guide?

Leak down test definite, look down the bores with a good endescope as well, any piston damage will also damage the cylinder bores as well.

Mark

28th July 2012, 10:27 PM	#16 (permalink)
Phil69 Phil69 is praying for sunny weather so he can polish the Skyline GTROC Member Join Date: Sep 2006 Location: RAF Coningsby near Lincoln Cars owned: Skyline GTR R33 V-SPEC Posts: 1,604	This might sound lame but, how do I do that? Not something I've tried before. __________________

28th July 2012, 10:33 PM	#17 (permalink)
R32 Combat R32 Combat is in limbo Spannering again. Join Date: Jan 2004 Location: Berkshire Cars owned: R33 GTR Posts: 7,645	You need an air compressor and a leakdown tester. It's a much better was of testing how well the combustion chamber is sealed. Google it. __________________ SKYLAB FUSION. The 3rd generation torque split controller for the ultimate driving experience. This replaces your old G-Sensor for a digital, faster responding, unit along with offering the driver the ability to alter the balance of the cars 4WD power delivery for the optimum balance. A free fitting service is available at Skylab HQ, which is postcode RG19 Limited offer Only £185. including p&p worldwide tracked postage Also available in the GTROC online shop To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

28th July 2012, 10:34 PM	#18 (permalink)
Phil69 Phil69 is praying for sunny weather so he can polish the Skyline GTROC Member Join Date: Sep 2006 Location: RAF Coningsby near Lincoln Cars owned: Skyline GTR R33 V-SPEC Posts: 1,604	Ahh right. I get it now. I assume it holds the pressure in so you can watch it over a period rather than the quick blast of pressure as you crank the engine for a compression test. Thanks for your help! __________________

28th July 2012, 10:38 PM	#19 (permalink)
R32 Combat R32 Combat is in limbo Spannering again. Join Date: Jan 2004 Location: Berkshire Cars owned: R33 GTR Posts: 7,645	I hope you get it sorted. __________________ SKYLAB FUSION. The 3rd generation torque split controller for the ultimate driving experience. This replaces your old G-Sensor for a digital, faster responding, unit along with offering the driver the ability to alter the balance of the cars 4WD power delivery for the optimum balance. A free fitting service is available at Skylab HQ, which is postcode RG19 Limited offer Only £185. including p&p worldwide tracked postage Also available in the GTROC online shop To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

28th July 2012, 10:48 PM	#20 (permalink)
DrGtr DrGtr is unaware they can edit their status GTR Register User Join Date: Jul 2009 Location: Cyprus Posts: 1,620	just start with a check list of a couple of things, leak test , even though if you have a good symmetrical compression test i would just unbolt the turbo first and be sure that its not the seals , i dont have the experience but my opinion is that is the turbo. __________________

28th July 2012, 10:51 PM	#21 (permalink)
Phil69 Phil69 is praying for sunny weather so he can polish the Skyline GTROC Member Join Date: Sep 2006 Location: RAF Coningsby near Lincoln Cars owned: Skyline GTR R33 V-SPEC Posts: 1,604	I already removed the front turbo and there is oil coming through the exhaust port into the manifold so the oil is from before the turbo plus, as said before, the inlet pipes are clean and there is oil on the piston. __________________

30th July 2012, 02:07 AM	#22 (permalink)
xxfr xxfr is hibernating GTR Register User Join Date: Apr 2009 Posts: 387	Sometimes the oil in the cylinder above the piston tends to seal and hold pressure, enough to give false compression readings. Do the leak down test as that will give you a better result. I have seen in big truck engines when rings give up and they start using oil like hell. The oil ends up in the cylinders from the bottom through around the rings and up. Put the same pistons back in with new rings and problem is solved. __________________

12th August 2012, 07:10 AM	#23 (permalink)
bucharest bucharest is 92' gtr. GTR Register User Join Date: Sep 2010 Posts: 62	i think maybe your turbo let go and the wet piston may be a different issue. one thats not such a big deal. how much oil on top we talkin bout tho ? and did plug 2 actually have oil on and look different than the rest ? and plus 1 for a leakdown test. __________________ Last edited by bucharest; 12th August 2012 at 07:17 AM..

12th August 2012, 08:37 AM	#24 (permalink)
Mark@Abbey M/S Mark@Abbey M/S is looking forward to racing on the circuits again soon GTR Register Trader Join Date: Feb 2002 Location: The workshop... Cars owned: Skylines... Posts: 3,284	Wet piston top as long as it isn't swimming in the liquid I wouldn't worry, when you run a car and turn it off and pull the spark plugs your see the top of the pistons still damp. If you put #2 cylinder to TDC can you put a long screw driver down the plug hole and touch the fluid and then inspect it? If you have neat oil in the down pipes and good compression's I would say you have a turbo failure. It does all seem strange that the car was running lean before you have the failure thou as these 2 items aren't connectted at all. __________________ Servicing/tuning all Skyline models since 1990 Ecutek/Cobb/Syvecs and Up Rev approved tuners In house Dynapack dyno Up to date diagnostics for all Nissan,s Consult 1/2/3 Laser 4 wheel alignment equipment Corner weight scales for trackset up Tuner of the fastest Rb26 powered car in Europe Any information needed give us a ring or mail us To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

12th August 2012, 08:46 AM	#25 (permalink)
Mark@Abbey M/S Mark@Abbey M/S is looking forward to racing on the circuits again soon GTR Register Trader Join Date: Feb 2002 Location: The workshop... Cars owned: Skylines... Posts: 3,284	Sorry just read the oil is coming down the exhaust port, no the turbo outlet. Can you see where the oil is coming from? Is it coming down the exhaust valve guide? Leak down test definite, look down the bores with a good endescope as well, any piston damage will also damage the cylinder bores as well. Mark __________________ Servicing/tuning all Skyline models since 1990 Ecutek/Cobb/Syvecs and Up Rev approved tuners In house Dynapack dyno Up to date diagnostics for all Nissan,s Consult 1/2/3 Laser 4 wheel alignment equipment Corner weight scales for trackset up Tuner of the fastest Rb26 powered car in Europe Any information needed give us a ring or mail us To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

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