gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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Following on from this thread http://www.migweb.co.uk/forums/engin...own-tests.html
And my quest to solve my oil burning mystery I conducted a compression test on my car. What do you make of the results:
Cylinder 1 dry 240 wet 270
Cylinder 2 dry 240 wet 270
Cylinder 3 dry 240 wet 250
Cylinder 4 dry 250 wet 250
Wet tests were conducted by placing 5ml of 10 - 40 oil in each cylinder and imediatly taking a test again.
Let me know what you think
Origionally was going to blame the cylinder head as its only had the problem since it was fitted. However after seeing these results im not so sure 
Drives supercharged Tec with torque  
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Dan295
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Registered: 9th Oct 06
Location: London
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i would say slightly warped head or a slightly dodgy headgasket imo of course, im not the genius that other people are
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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if its the head the readings shouldnt have gone up when oil was added though
Drives supercharged Tec with torque
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Dan295
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Registered: 9th Oct 06
Location: London
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what should it be?
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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Theres no definate saying what they should be. Should just all be fairly equal on dry which they are.
When you add a small amount of oil that seals the rings. Therefore if the seal becomes better with oil. ie higher reading the rings maybe leaking.
As far as I understand anyway 
Drives supercharged Tec with torque
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Dave A
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Registered: 10th Dec 03
Location: County Durham
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those results seem fine, a difference of 10-20% is normal between a wet and dry test.
done a leakdown test?
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Richardhhha
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Registered: 29th Sep 07
Location: Croydon, Greater London
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if its burning a lot of oil, easy easy test is to take the car for a nice drive, get it on a hill doing about 30 and use the engine breaking to slow you down when you get to bottom of hill boot it, (someone has to be behind you tho) and see or blue smoke! If smoker its rings. Other than that i would be looking at valve guides and valve guide oil seals!
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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quote:
Originally posted by Dave A
those results seem fine, a difference of 10-20% is normal between a wet and dry test.
done a leakdown test?
No, having trouble finding somewhere local that will do it
[Edited on 18-02-2008 by gavin18787]
Drives supercharged Tec with torque
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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quote:
Originally posted by Richardhhha
if its burning a lot of oil, easy easy test is to take the car for a nice drive, get it on a hill doing about 30 and use the engine breaking to slow you down when you get to bottom of hill boot it, (someone has to be behind you tho) and see or blue smoke! If smoker its rings. Other than that i would be looking at valve guides and valve guide oil seals!
It does smoke but very little. Get a bit after about 6.5k to the 7,800 rpm limit. Its not noticable from the car but if someone follows they can make out a bit and say it smells like burning (sorry mothers description )
Does about 1 litre every 500miles so I would expect more smoke tbh
Drives supercharged Tec with torque
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Richardhhha
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Registered: 29th Sep 07
Location: Croydon, Greater London
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i know you can rase the rev limit on the xe engines but i would say you scorched the rings mate.. try what i said and if there is a big puff of blue then defo rings. if not i say its oil seals
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luke85
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Registered: 26th Nov 07
Location: Chesterfield
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If its smoking at full throttle then Id be thinking towards the piston rings as well.
When my valve stem oil seals had gone It smoked a lot worse at part throttle than at full throttle
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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quote:
Originally posted by Richardhhha
i know you can rase the rev limit on the xe engines but i would say you scorched the rings mate.. try what i said and if there is a big puff of blue then defo rings. if not i say its oil seals
Rev limit has only been raised recently had the problem before
Drives supercharged Tec with torque
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Dave A
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Registered: 10th Dec 03
Location: County Durham
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very difficult to diagnose this problem over the net mate, my engine (the tb'd one) uses a fair amount of oil when used hard but its a precision built engine, 0% leakage accross all 4 cylynders and new everything including head casting and pistons! I put my oil loss down to high revs and an engine that gets used hard.
have you checked your breather system?
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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havent checked the crank case one, thats on my to do list. So blow down that and air should come out the dipstick hole?
I drive sensibly to work etc during the week nothing over about 3.5k and it still uses a fair bit of oil so there is definatly a problem i think 
Drives supercharged Tec with torque
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Dave A
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Registered: 10th Dec 03
Location: County Durham
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yes, blow down it and it should be completely free to come out of the dipstick hole.
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gavin18787
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Registered: 22nd Feb 05
Location: Basildon, Essex
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Ok I will do that and report back 
Drives supercharged Tec with torque
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