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Burning Oil?

966 views 7 replies 5 participants last post by  DrSquirley 
#1 ·
my n/a900S has small bit of smoke coming out of oil fill/check tube and the levels are very low. what other symptoms would there be and what could be causing this. the tappets are very worn an noisy could they be the culpret?

edit: been thinking, could the oil pickup screen be clogged? would that produce those effects? im pretty it would cause the noise of the tappets...
 
#2 ·
Cheap answer
The noisy tappets could well be due to the low oil level as could smoke/vapour from the filler tube (oil gets very hot if the level's too low).

Expensive answer
Smoke may also be due to piston blowbye. This indicates wear to the engine bores. If this gets too bad it means a major engine rebuild.

I suggest you fill the engine up to max oil level and let it tick over. See if the noisy tappets go away.

I would also look into the cause of the low oil level before I went on another journey - its a lot cheaper than getting the car recovered. :-?
 
#4 ·
gerryp said:
Expensive answer
Smoke may also be due to piston blowbye. This indicates wear to the engine bores. If this gets too bad it means a major engine rebuild.
And how would i prevent this, keep the oil up? is there anything else i can check in regard to the engine bore wear? is it caused by heat? poor oil? over use/high rpm?
 
#5 ·
clearly im the only one posting here, but at least im solving problems.

ok, the news is that it wasnt getting dangerously low because it was burning it all, theres a confirmed leak somewhere, i can see it on the floor

next question is, where are the spots to look for this leak?
 
#6 ·
You can check for piston-blowby by doing a compression test. record all the pressures of the cylenders, know inject a small amount or oil into the cylender using a syrige. If know try another compression test. The oil will temporarly seal the rings if you are expexencing blow-by. this will create a higher pressure in the cylender than the first test. Make sure you test the compreccion with no s-plugs, and WOT.
 
#7 ·
DrSquirley said:
clearly im the only one posting here, but at least im solving problems.

ok, the news is that it wasnt getting dangerously low because it was burning it all, theres a confirmed leak somewhere, i can see it on the floor

next question is, where are the spots to look for this leak?
First place I would look is the oild drain plug.... very often the washer is not replaced after a change or it is simply too slack.

then, head gasket.... You would typically think that if a head gasket had blown it would be visible from the performance and all the fluids geting mixed up.... but, a gasket can crack at on the outside edge allowing oil to seep down the block only slightly affecting oil circulation/pressure (tappets etc).

Is the rocker cover tight enough?

Hope you locate it.... maybe a steam clean will help.
 
#8 ·
garry said:
First place I would look is the oild drain plug.... very often the washer is not replaced after a change or it is simply too slack.

then, head gasket.... You would typically think that if a head gasket had blown it would be visible from the performance and all the fluids geting mixed up.... but, a gasket can crack at on the outside edge allowing oil to seep down the block only slightly affecting oil circulation/pressure (tappets etc).


its beginging to seem like the head gasket but my fluids are still clean, so perhaps the break is on the outside edge. also, its been running idle a little high lately, not too much jsut more around 1000 rpm instead of 8500-9000 would this point to head gasket or just in need of some throttle body and aic cleaning? (vacuum sys checked out)

perhaps piston ring is gone though, ill do a compression test monday, i probably shouldnt be driving her around right?
 
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