The-LS

The motor has 120,000 miles on it. 40,000 of it was boosted. I'm running 10W-30 regular oil and recently (past 2 months) the car has been buring oil like crazy. VERY visbile on the highway when boosting, trailing with a bluish smoke screen that continues to billow out as the car is pushed with the accelerator floored. City cruising I cannot see any oil visibly burning when I look in my rear view.

There was one time when I was running Valvoline SynBlend 10W-30 and that oil was buring EVERYWHERE I drove regardless of how I drove, city, highway, hard, or babying it.... it just had a continuous fog coming out.

I did a lot of searching and I'm guessing it has something to do with my valve guides or seals. I would like to see input from those who have knowledge about motor internal workings, or just personal experience.

Some info about the car:

JRSC 8-9psi
Walbro Fuel pump
Skunk2 Cam Gears (dyno Tuned)
440cc Injectors
Uberdata ECU. (car runs between 12:1 - 10:1 A/F richer in the higher gears)
Full USDM Type-R Exhaust w/ 2.5" Carsound Cat

If not mentioned, everything else is stock.

Compression and Leak down results today:

Cylinder......... Compression............ Leakdown
Cyl 1 ............ 215 ............ ............8%
Cyl 2 ............ 210 ............ ............5%
Cyl 3 ............ 210 ............ ............4%
Cyl 4 ............ 208 ............ ............10%

Jared

tear it down and rebuild. rings are the culpruit

DefiantGSR

isn't leakdown a sign of bad seals?


why the heck would rings be the culprit if his compression is pretty good?

primeredbeast

might help a little if you go to a little heavier oil but unltimately rebuild it

wantboost

iTrader: (2)

has anyone bothered to ask about the head? the valve seals could be going bad or have already gone bad

fullracegsr

drop a tablespoon of oil in each cylinder and redo the comp test... if the numbers go up then the rings are no good... if numbers stay the same could be valve seals...

The-LS

forgot to add that I'm also running a oil catch can. The amounts of oil going into the catch can seem normal. I've run compression tests previously in the past when the car was boosted at 6psi and the numbers have come back relatively the same ~210 across the board and back then I did NOT have abnormal oil consumption or a smoke screen coming out the rear, and it had a test pipe then.

One thing that also comes to mind right now is I've removed a PCV valve I had installed onto the line from the intake to valve cover. I had the PCV valve to ONLY allow fresh air INTO THE VALVE COVER. Is it possible the JRSC is sucking to much at 9psi now that its pulling oil out of my valve cover into the combustion chamber? This just dawned on me, so I may yank the hose just off the valve cover and run without it if to see if anything changes (this will be the same as having a breather on the valve cover).

99B16Si

valve seals
pcv
too much oil

are the only things that come to mind. try removing any lines that can pull oil into the intake track to see if that helps

The-LS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99B16Si &raquo;</TD></TR><TR><TD CLASS="quote">valve seals
pcv
too much oil

are the only things that come to mind. try removing any lines that can pull oil into the intake track to see if that helps</TD></TR></TABLE>

what about valve guides? the cloud of oil smoke is most visible under hard acceleration and cintinuous with boosted acceleration. Does my head have to come off? How much am I looking to spend? I really don't want to put anymore money into the car, and if the cost is too much I may just sell the entire car... I would like to be able to keep her a little longer though, the car is in otherwise great condition for a 1995 car.

ladysman

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Black-LS &raquo;</TD></TR><TR><TD CLASS="quote">

the cloud of oil smoke is most visible under hard acceleration and cintinuous with boosted acceleration.
</TD></TR></TABLE>
This here tells me it is the rings. Listen to Jared.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Black-LS &raquo;</TD></TR><TR><TD CLASS="quote">
Does my head have to come off? How much am I looking to spend? I really don't want to put anymore money into the car, and if the cost is too much I may just sell the entire car... </TD></TR></TABLE>

Of course it will have to come off if it is the rings. Cost depends on you. Easily 1g to do it somewhat right.

yellowturbo

maybe its the turbo seal... I dont see anything wrong with your number in the compression test, leakdown.

ladysman

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by yellowturbo &raquo;</TD></TR><TR><TD CLASS="quote">maybe its the turbo seal... I dont see anything wrong with your number in the compression test, leakdown.</TD></TR></TABLE>

Read his setup again.

The-LS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ladysman &raquo;</TD></TR><TR><TD CLASS="quote">
This here tells me it is the rings. Listen to Jared.

</TD></TR></TABLE>

my compression numbers, like others have stated lead me to believe the piston rings should be fine. could it be my oil rings? I appreciate the comments and insights to my problem, and I know the RIGHT thing to do is tear down and take care of everything while the motor is apart. But I'm getting old and don't want to put anymore money into this car. $200-$300 would be okay... even if the car was in great shape I'd still sell her in a year and move on. but she is still fun to drive and I would love to be able to keep her for another year and not have a smoke screen coming out the rear. I'm just trying to explore all possibilities and options at this point.

VTC_CiViC

Compression is good, leakdown is satisfactory.. I say valve stem seals.

fullracegsr

why dont you just put a tablespoon of oil in each cylinder and redo you comp test... if the number go up then rings are shot... if they stay the same your numbers are else where.... no simplier a check than that

Jared

in many cases you can have good compression numbers and still have weak oil rings. it happens. valve seals wont smoke like you describe, hell i run my motors with no valve seals on th exhaust side and they dont smoke like that. bite the bullet, pull the head and rering the engine if you dont find a melted ring lang.

ladysman

From experience, you can have awesome compression and leakdown numbers and it still be the rings/hone job.

For example, mine was 230 compression across with less than 1% leakdown across. It used 1 quart every 200 miles (or more). It was either the oil rings not doing their job or out of round cylinders.
Yours being a stock engine with the mileage, I still say rings.

I'm still with Jared on this one.

The-LS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ladysman &raquo;</TD></TR><TR><TD CLASS="quote">From experience, you can have awesome compression and leakdown numbers and it still be the rings/hone job.

For example, mine was 230 compression across with less than 1% leakdown across. It used 1 quart every 200 miles (or more). It was either the oil rings not doing their job or out of round cylinders.
Yours being a stock engine with the mileage, I still say rings.

I'm still with Jared on this one. </TD></TR></TABLE>

this is the type of comments I was looking for. not saying I'm happy to hear its my oil rings. but you are speaking from experience and your example sounds almost identical to mine, good compression and leakdown numbers but burning lots of oil. I'm doing about 1 qt. per ~200 miles as well depending on the weight of the oil now.

so most likely my compression rings are good but my oil rings are bad right? will the tablespoon of oil in each cylinder and redo compression test tell me if its the OIL rings? I get a feeling the answer is "no".

fullracegsr

i dont believe it will tell you exactly what ring is bad... i was just suggesting trying that for a quick check... most cars i have found with bad rings the compression numbers jumped up with oil... i havent had any with good comp numbers and still being the rings that are the culprit... just trying to help

94whtgsr

turbo seals for sure man...

Mag00n

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94whtgsr &raquo;</TD></TR><TR><TD CLASS="quote">turbo seals for sure man...</TD></TR></TABLE>

Read the thread for sure maaaaaaaan

Jared

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94whtgsr &raquo;</TD></TR><TR><TD CLASS="quote">turbo seals for sure man...</TD></TR></TABLE>

you have smoked yourself retarded

Muckman

iTrader: (2)

As much as everyone likes to use compression testers and leakdown testers to diagnose bad rings - The top piston ring holds back most of the compression and theres 2 rings below that can be damaged and not show up on either test.

Nothing burns that much oil except for bad rings.

m R g S r

Hmm. . mine does the same thing, but not as rapidly. I say 1 quart every 600-1000 miles. .

The-LS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">Nothing burns that much oil except for bad rings.</TD></TR></TABLE>

yea, as much as I didn't want that to be the case.... I'm going to agree that is the case, I just wanted other's opinions first before I just take 1 person's word. The mechanic performing the tests said he felt it may be the oil rings too, but with a high mileage car he said it could be a combination of many parts leaking oil into the combustion chamber.

oh, well... now I gotta decide what I'm going to do with the car.