oil catch full, TOO MUCH BLOW BY

[jdms13rhd]

I got a 90 GTR with oil cooler big trust I/C, Profec B/C and thats pretty much it for performance upgrades. Boosting just under 1 bar.

Now I had a boost leak and fixed it and cleaned everything up good and it hauled ass. Still does but the problem is that my Damn oil catch got half full of me rippin hard for about 60km. I did a leak down test on each cyl and NO 1 and No 6 cly's arnt sealing well. I was running 10w30 synthetic.

I am thinking that the car sat for a long time in Japan and that there is a bunch of crap in the oil since I did the first oil change and the oil got dirty fast. I am also going to do a couple more oil changes with mineral oil with more heavy weight and run it for a bit and clean everything out just in case there is some crap in the rings. Other than that im convinced that the rings in the NO 1 and 6 CYL's are done for and I either need new long block or a rebuild. If you guys know of this problem or know of anything else I can try to help my car out it will be greatfull.

BTW the catch has one 5/8" line from the driver side rocker that goes to the Battery area and I still have the tube conecting the covers together. Cheers!

[qualthar]

A couple points.

1. WHERE ARE THE PICS!!!

2. You coming to Red Deer on Sunday?

I can't actually help with your problem, but I do think a few oil changes to flush out the system could do some good. Good luck with the car!

[CanadianGTR]

I thought mineral CAUSES build-up, and synthetic cleans...

Using mineral all-together instead of just using it to "clean things out" might help since it has a tendancy to leave deposits which can actually seal small leaks.

Also: what are your compression numbers?

[jdms13rhd]

Okay I dont think the compresion tester I was using before was 100% good so I got a new one and wow these numbers suck. I cant believe it ripped so hard. It also doesnt smoke out the tail pipe and idles awsome!

DRY NO 1:90
2:50
3:120
4:80
5:48
6:60

WET NO 1:215
2:162
3:210
4:160
5:150
6:140

Im going to wait till the cyl's are dry to do another Leak down test and I will post the results later too.

[tyndago]

Okay I dont think the compresion tester I was using before was 100% good so I got a new one and wow these numbers suck. I cant believe it ripped so hard. It also doesnt smoke out the tail pipe and idles awsome!

DRY NO 1:90
2:50
3:120
4:80
5:48
6:60

WET NO 1:215
2:162
3:210
4:160
5:150
6:140

Those numbers are all over the board. Are you sure the compression tester and the tester are correct ?

Ever use a leak down tester ? Its a much more accurate test. I hardly ever use a compression tester.

GT-R's move a lot of oil. If you are having problems, and dont want to rebuild the motor - you might want to try and run a drainback into the sump. T it in with the oil drain line.

It wont "fix" the problem, but its a fix for a problem.

[jdms13rhd]

well I have done a leak down test on all cyl's and they are all poor. I used my old compression tester the first time and didnt believe the numbers like you did so I got a brand new one and numbers were pretty much the same.

This car ran fine one minute and the next it sucked. It must have had good compression then BAM, it went down the shoot. I still dont understand what hampned. Maby the person in Japan knew the compression sucked ass and put that stop leak **** in the engine and when I did the oil change it went away causing it to suck ass. Im not too sure about that though. I have talked to many people and a good friend in AUSI that rebuilds rb's every day and he doesnt get it either.

Like I can understand loosing compression in 1 or 2 cyl's but not all 6 at the exact same second.

Now the car runs like **** and smokes at idle and wont run if I plug the oil catch line. which is prob the rings. I dont think I will get a good anwser until I tear downb the engine and take a look at what hampned.

When it hampned I was running 12-13lb boost 94oct gas and didnt rev over 8xxxrpm so nothing any GTR would see out of the normal.

I have looked at rebuilding it and doesnt seem it will cost too much anyways so it will be fun but if someone wants the car the way it is I might just sell it. I have too many projects at the monment and I got another GTR coming one the way.

Any more coments on this issue will be great!!! Thanks!!!

[SalEsh]

wow can u say strut bar... wowowowzers i like


Brandon

[tyndago]

I dont understand having 6 bad holes all at once. Normally thats only from bad machine work or assembly.

Normally you will only see 2 or 3 bad holes at the most on a motor thats been beat...

You said with oil the compression went up right ? Not bent valves ?

[jdms13rhd]

Yes I know. That is whay I am so confused. This makes no sence