Too Much Blow By?

[Shockster0429]

I've got a freshly rebuild rb25/26 motor, je pistons, eagle rods, 26 crank, acl, arp parts about 800 miles on it. Did some tuning this weekend trying to remove excess fuel in the maps. I'm using a mircotech lt12s unit. 67mm turbo (16-17psi 93octane timing 16 degrees at WOT) About 2-3 weeks ago (500 miles on motor) I noticed my valve cover tubes being pushed/shot off after boosting. (bad sign) I had them vented ATM where the PCV should be.

Comp Test

1. 145

2. 150

3. 140

4.135

5.125

6.150

Number 5 cylinder, didn't look good... Leak down.

1. 2%

2. 1%

3. 3%

4. 4%

5. 7%

6. 1%

Ok not too bad... tops of pistons all have a slight sludge/gooey oil slime on them. Engine is blowing a bit of blue smoke, when throttle is blimped. Black under full boost. No smoke under normal driving.

Builder feels I might have scuffed my new rings from washed out cylinder walls or glazed walls. I feel the same personally. Plugs are all burning pretty equally. I hooked up my rockers to the intake for some vac under boost, now seeing about 2 table spoons of oil in intake pipe after 200k.

Tracked her yesterday, was on street tires (should have brought the DR's). Trapping 110mph 2.35 60ft 86mph trap at the 1/8.... now granted I'm spinning till about the 1/8th while pedaling but I feel that my trap pick up between the 1/8th and the 1/4 is way low from what it should be seeing I'm WOT not spinning. A/f's are 11.0's at full boost with 16degrees of timing once again, intake temps at 32 degrees, water 88 degrees.

You guys thinking what I'm thinking?... rings/walls arn't in ideal shape...

thanks in advance.

Edited June 2, 2008 by Shockster0429

[Sydneykid]

What oil did you run the engine in on?

Cheers

Gary

[Shockster0429]

What oil did you run the engine in on?

Cheers

Gary

Rotella T 15w40 Diesel Oil, its conventional. Builder recommended it for the added Zinc to help the break in process.

[STATUS]

im thinking poor build, but i also dont like using diesel oils for run in... many do i dont.

[Shockster0429]

im thinking poor build, but i also dont like using diesel oils for run in... many do i dont.

poor build as in improper bore to ring tolerances?

[VB-]

93 octane fuel? are you in the US?

Edited June 3, 2008 by VB-

[Shockster0429]

93 octane fuel? are you in the US?

93 octane yes I'm in the U.S.

[R34GTFOUR]

that compression test tells the whole story, the motor is a breather. If my 100k km old engine had a 25psi variance between cylinders i would strip it down, having that sort of variance on a new built motor is pretty bad...

Pop the pistons out, re hone it and put new rings in and check the clearances then take it from there. Hopefully you're not too unlucky and have to rebore it and stick new pistons in

[Shockster0429]

that compression test tells the whole story, the motor is a breather. If my 100k km old engine had a 25psi variance between cylinders i would strip it down, having that sort of variance on a new built motor is pretty bad...

Pop the pistons out, re hone it and put new rings in and check the clearances then take it from there. Hopefully you're not too unlucky and have to rebore it and stick new pistons in

Its looking like thats what I will be doing...

Well, got some awesome results from the latest compression test. I let the motor warm up to operating temp while idling... here is the run down!!!

1 - 132psi

2- 132 psi

3- 132 psi

4- 118 psi

5 -118 psi

6- 72 psi (ouch)...

So hmm bad of course, lets put about a table spoon of oil in each cylinder and try again. (testing to see whats causing the leak)

1- 180psi

2-175 psi

3- 155 psi

4-188 psi

5-170 psi

6- 157 psi

Yeah my rings are definitely not seating/scuffed/****ed all of the above?

Heres some pics of what I was talking about.

Poping off hose

Mess its making on my hood when it does.

150 mile old Rotella T 15w40 diesel oil

.. nice and black

Plugs burning equally, have a bit of fuel on them from the cold start. (motor leans out to 14.5's once warm at idle) The rest on the threads seems to be nasty oil ****

#6 cylinder (72psi one)spark plug showing no signs of pre-det

Nasty goo on the tops of my pistons I scraped off with a magnet

So yeah, rings are looking like they are at a point of no return since the comp test has gone down since the one ~ 2 weeks ago....

Most likely will be pulling the head this weekend to get a closer inspection..

I'll be calling my builder tomorrow to let him know whats up.

These are JE pro-seal rings and pistons as well, opinions on them anyone?

[STATUS]

i would pull engine, something has even scored your cam lobe.

[msnismo]

:Dave here:

umm thats freekin nowwhere!!!

time to find a new machine shop. ive seen je on a sr20 with 6 thou clearance and have no dramas at all. i will be very interested to see what the bores look like once you pull off the head!

some bad news dude, but its looking pretty terminal. whats the blowby like?

ive run engines in on mobil 1 rite down to penrite "running in oil" and have had no issues at all with ring seating. just takes longer with the synthetic.

either its binding the rings and broke them or there is like 40thou ring gaps lol..