I recently bought a project car, it had no compression on no 1 cyl. It also was burning oil. Upon disassy i found a cracked exhaust valve.removed and replaced bad valve and all seals. Cleaned head mating surfaces as best as i could .Reassembled now i have great compression but still an oil intrusion issue. Please heeeeeeeeeeeelp!!
2006-11-26 13:41:14 · 13 answers · asked by recoyle3 2 in Cars & Transportation ➔ Maintenance & Repairs
The most common sources for oil in the cylinders are leaks from the valves, and worn piston rings.
If you did a compression test and all cylinders show a similar drop in pressure from the minimum spec, then that confirms the leak is across all cylinders, and it's due to one of the two sources above.
You can check for leaking oil past the rings by doing another compression test after pouring about 1 teaspoon of oil down the spark plug hole and checking compression, one cylinder at a time. If the compression increases, then you temporarily sealed the leak and you know to replace the rings. If the compression does not change, then the oil leak is most likely coming from the valve guides.
When you do a valve job, you should check the valve stem clearance and play in the valve guide. If too much clearance, you can have the guides 'reamed' to reduce the stem to hole clearance, and that should reduce oil leakage down the valve stems.
2006-11-26 15:27:23 · answer #1 · answered by Tom-SJ 6 · 0⤊ 0⤋
Firstly your compression reading should be consistent between the 4 cylinders. The difference should not be greater than 5 to 8psi as an example (check your servicing manual).If there's no leak of compression, top up your engine oil, start your engine & stop it after running for 10 to 12 seconds. There should be a drop in the engine oil level. This shows that the engine oil is getting into the cylinders & circulating in the engine oil system.
2006-11-26 13:59:44 · answer #2 · answered by Howard Teo 3 · 0⤊ 0⤋
Well lets think about this, the fuel is pressurized along the fuel rail going to each injector and the injector is electronically activated to open at a specific time, then it closes when no electronic signal is sent to it by means of a spring, within this little thingamabob called an injector is a seat so that no fuel can leak past in the closed position, however even when you turn the engine off there's still residual fuel pressure within the fuel rail, so what do you suppose will happen if one or more of the seats in the thingamabobs were leaking? come on think about it, might that leak into the cylinder and past the piston rings into your engine oil? If I were to have to guess I'd say yes that could be a very good explanation. and no I have no ASE certs, I wont even get out of bed for the money you make working on passenger cars
2016-05-23 07:11:15 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I think it's coming from the valve guides. You say good compression. Has to be a valve guide. maybe that is why the valve cracked in the first place over heated from oil running down the valve and burning it up. Sorry!
2006-11-26 13:54:27 · answer #4 · answered by Bill M 2 · 0⤊ 0⤋
head gasket and win you put in new exhaust valve the guide was probable bad needs head work sucking oil down valve stem you can do the compression check again and see what it reads or a norther thing you can go is get a feting that go's in the spark plug hole and put compressed air in the cylinder if you hear excess air you no you have got a leak. i could go on &on but this mite help point you in the right derection
2006-11-26 13:52:00 · answer #5 · answered by master of none 3 · 0⤊ 0⤋
Don't know how old this project car is or what it is...BUT,an oil
burner PLUS lack of compression would certainly indicate to me
bad rings and/or blown piston LEADING to such things as bent,
cracked,burnt valves.
Sorry,but it sounds like a "tear-down" to me.
2006-11-26 14:10:55 · answer #6 · answered by huppercupper 3 · 0⤊ 0⤋
Frist what kind of car is it? and what size motor?
my quess would be piston rings gone bad will u are puting new piston rings on replace the head gasket and your oil pan gasket and put a new timeing belt on and that motor should be good as new
2006-11-26 15:23:22 · answer #7 · answered by davedebo198305 4 · 0⤊ 0⤋
Your cylinder rings are leaking, that would also account for oil in the cylinder. Do a compression test on that cylinder....KECK
2006-11-26 13:46:51 · answer #8 · answered by Tneciter 3 · 0⤊ 0⤋
do a compresion test and then a leak down i bet either a valve seal is damage or a ring land is cracked,
2006-11-26 15:20:44 · answer #9 · answered by Anonymous · 0⤊ 0⤋
oil could be getting in past your rings did you check any of your block components and have the head magnufluxed to check and see if you had any cracks?
2006-11-26 13:44:25 · answer #10 · answered by wrenchbender19 5 · 0⤊ 0⤋