Forged Engine Using Oil

[sickr33]

my new forged engine is using about 1 to 1.5L of oil per 2500km

compression test shows 155 to 160psi across the board

i cant see any oil leaks.

very little oil in intercooler piping.

have been told the car blows the blue/black smoke under throttle.

the motor does breath quite a lot (white smoke out of the oil cap when removed).

i get a (brown water) like liquid in catch can.

im hoping it is my turbo seals

can a turbo seal leak into the exhaust housing and not the compressor housing?

so i ask can anyone shed some light on this problem.

cheers

Ryan

[STATUS]

engine has an issue, should be no breathing at all.

[sickr33]

what can i do to find out what

[STATUS]

leak down test... but if your using oil and the oil breathers are fuming... its not a good sign.

[The Mafia]

+1 on the leakdown test.

Compression tests don't really mean shit these days.

This will tell you instantly if your rings are rooted.

[Smegul]

+1 on the leakdown test.

Compression tests don't really mean shit these days.

This will tell you instantly if your rings are rooted.

whats a leak down test?

[TiTAN]

do a fairly agressive leak down test on it (@ operating temp), it will tell you whats going on.

Here's one we did not long ago.

CYL COMP LEAK DOWN

1 155 10-16% @100-110psi

2 155 10-16% @100-110psi

3 155 10-16% @100-110psi

4 155 10-16% @100-110psi

5 155 10-16% @100-110psi

6 155 10-16% @100-110psi

http://www.carcraft....ster/index.html

[sickr33]

i have found another symptom

some times when the car is running only on cold start i believe have not confirmed this yet

if you hold your hand behind the exhaust you get little black specks on your hand i believe this might be the oil i'm loosing.

please share your opinion but i believe this to be a good sign that the turbo's are leaking the oil.

my reason for this is the if it were the rings the oil would be burnt rather than spat out the exhaust.

also i assume that this would only occur when the exhaust is not hot enough to burn oil hence only happens on cold starts.

what are your thoughts people

[DVS JEZ]

it will be condensation build up in the exhaust and its mixed with the black soot and being spat out the end.

[Beer Baron]

i have found another symptom

some times when the car is running only on cold start i believe have not confirmed this yet

if you hold your hand behind the exhaust you get little black specks on your hand i believe this might be the oil i'm loosing.

please share your opinion but i believe this to be a good sign that the turbo's are leaking the oil.

my reason for this is the if it were the rings the oil would be burnt rather than spat out the exhaust.

also i assume that this would only occur when the exhaust is not hot enough to burn oil hence only happens on cold starts.

what are your thoughts people

sorry but that's normal. it's just a build up of moisture and carbon blasting out the exhaust on start-up. I've owned over a dozen GTRs and all have done it. it's not oil. my old GTR with no cat etc painted the wall behind it completely black after a short while just due to that.

[Nee-san]

Considered a crack in sump ?

[FJdat]

Are there any oil stains on your driveway/garage? I

would suggest getting the whole engine degreased properly on a hoist, then drive the car for a few days and see if there any leaks.

if there aren't any physical leaks then it sounds like it maybe worn valve guides or valve stem seals

[Sinista32]

"my new forged engine is using about 1 to 1.5L of oil per 2500km"

+1 for leak down test.

+ my 2cents

Check for wet oil on plugs to see if your oil is being pushed up/sitting on top of your pistons,

Drain oil to see if there is fuel in your oil pan.

Consider not driving it, if you can, until you work it out as it can lead to another re-build..

[MrStabby]

Drain oil to see if there is fuel in your oil pan.

You could send the oil away for analysis - that can tell you if there's abnormal piston/ring or bearing wear, how much fuel is in the oil etc.

[tridentt150v]

if there aren't any physical leaks then it sounds like it maybe worn valve guides or valve stem seals

bingo.....didn't look at the head when you did your build!!!!

[r33_racer]

If its using oil when on the throttle it generally wont be valve guides or seals, that generally only happens at idle and on decel. Oil burning under load is usually always rings. Could be wrong cross hatch angle, damaged rings, scratches in bore from improper assembly or dirty assembly, poor initial break in and the list goes on.

Have you done the leak down test yet?

[Rolls]

when my turbo seal went I had this exact problem, compressor made love to the housing not long after. Never checked the catch can though as it is a gay one where I have to remove it to drain it.

Edited January 31, 2011 by Rolls

[Beer Baron]

yeah I would be sending the oil away for analysis. it's cheap (under $50) and will tell you what is going on. and yeah get the leak down test done too, it's not hard.

[sickr33]

i jacked the car up nice and high to day and i have noticed i have an oil leak

it appears to be the return oil line for the front turbo.

general area around is oily but not dripping!

i am pleased to have found this as i have a new set of gt2860-5 along with Tomei manifolds and dumps to go in the next 2 weeks

i hope this is the only oil consumption

[STATUS]

i jacked the car up nice and high to day and i have noticed i have an oil leak

it appears to be the return oil line for the front turbo.

general area around is oily but not dripping!

i am pleased to have found this as i have a new set of gt2860-5 along with Tomei manifolds and dumps to go in the next 2 weeks

i hope this is the only oil consumption

to lose 1-1.5l per 2500km it should be soaked.