390 engine covered in oil need help!!!

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Relaxedarnold

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I have a completely performance built 63 cadillac 390 engine, I'm having problems with oil blowing out of the oil filler breather tube. I've checked the pcv valve it's brand new. I have the pcv valve hooked up to the port in my carburatored spacer. Any ideas?? Can't find the problem
 
New rings aren't necessarily seated yet. Requires some running under a load to accomplish. Also, some oil additives can prevent ring seating.

Let's start with this...
 
Using autozone 10/30 oil in the motor has under 1000 run time miles on the motor. Never did this before the rebuild. Don't understand why it's doing it now, I can make it do it in the driveway slow bringing the motor up to wide open throttle
 
The old rings were seated and broken-in before the rebuild. New rings have to be run-in under load after rebuild.

Light driving may not do it. It's not advised to go by the manual's recommendation of driving easy for the first xxxx miles. It needs to be run somewhat briskly, minimum. Just not full rpm, esp. if you have tuning issues. Ring material matters, as much as cylinder finish.

Has the problem always been there since the rebuild?
If so, I'll get into more detail.
 
8ad-f85 said:
Light driving may not do it. It's not advised to go by the manual's recommendation of driving easy for the first xxxx miles. It needs to be run somewhat briskly, minimum. Just not full rpm, esp. if you have tuning issues. Ring material matters, as much as cylinder finish..
Click to expand...

1000 miles already


8ad-f85 said:
Has the problem always been there since the rebuild?
If so, I'll get into more detail.
Click to expand...
85 he did say it has


Read this yesterday didn't want to say it first.. But sure sounds like broken rings or ring lands
Having that much crankcase pressure WITH a pcv hooked up is a big alarm to me

Do a compression or leak down test..

I wouldn't run it anymore till you make sure it aint this.. youll just be doing damage if you do

What kind if rings did you use? ... What kind of ring compressor ? and are the pistons cast
 
I hate to be gloom and doom, but:

What do plugs look like? One or more oiled, compared to others?

I would do compression test AND leakdown test
 
Exactly, step by step.

One thing I do in cases like this is chuck some air into the cylinder at TDC and listen to where the sound comes out. Valve leaks come out the carb or tailpipe, rings are heard from an oil cap or PCV opening. Make sure your breaker bar is off the crank, just in case...
Is one cyl. much worse? Compression test narrows down the bad hole...

I knew about the 1000 miles, that doesn't mean anything. Many factors here.
One way of proving the rings are seated is to note the temp gauge under those break-in miles. When you load it real good, the temp rises.
Eventually you will see that the range of temps (rise and fall) will get closer. This is a good indicator of ring break-in.
If the vehicle won't ever get raced, I've recommended a procedure...
Get as much weight packed into it and take it on a long trip, such as a freeway loop. Alternate loading it, enough to watch the temp gauge climb, then easy to cool it. You will see when it's "broken -in".

Have you run it really hot since the rebuild?
 
Did a compression test on all cylinders here's what I got:
1- 190. 3- 190. 5- 190. 7-180.
2- 150. 4- 190. 6- 180. 8-180.
My concern is cylinder 2 is low. Did a wet test came up with same 150 on the cylinder
 
Relaxedarnold said:
Did a compression test on all cylinders here's what I got:
1- 190. 3- 190. 5- 190. 7-180.
2- 150. 4- 190. 6- 180. 8-180.
My concern is cylinder 2 is low. Did a wet test came up with same 150 on the cylinder
Click to expand...

#2 plug wet?

If you don't have a leakdown tester, do you have a way to put compressed air into the plug hole? Adapt the hose from the compression tester to air hose?

If you can do so, and hear air hissing out of the oil fill, you'll know that you have a bad problem.

Btw, that's a helluva big psi number. Are you sure about the gauge? I can't imagine a stockish engine [stock replacement pistons, etc] would crank that high. Check it on another engine to be sure? If psi is normal [lower #s] on another stock type engine, I might suspect the cam is in way advanced.

In any case, if it really pumps 180-190, imo, that's really pushing it on pump gas. Did the engine "rattle"? [detonation]

Dave
 
I agree with Dave, if that psi is correct its probably rattled and butted a ring. My motors just shy of 12.1 with a tight lsa cam and only cranks a little over 200 psi. No chance of running it on pump gas. Did the rebuilder use stock type pistons?

Robbie
 
My motor isn't stock here's the specs:
I have a 63 cadillac with a 390. I pulled the motor an did a full rebuild as follows:
Block bored .060 over
Egge pistons 10.5:1 compression
Heads ported with 2.02intake 1.60exhaust valves
Cad500.com valve spring kit, timing chain kit
Isky cam from cad500.com 435 lift duration 208 lobe center 108. Timing duration 262
Modified intake with 1" open spacer, all exhaust ports filled an intake gasket that blocks off the center
Holley 750 double pumper
Mallory electric fuel pump reg. at 7psi with 3/8 AN fittings lines
Crane ignition XR-I with autolite plugs one stage hotter gapped at .050"
 
Awful lot of compression for a tiny cam...detonation. Damaged piston or ring.
Sorry to be the harbinger of doom... :D
FWIW, Egge pistons won't tolerate much abuse.
Not minimizing quench distance or softening sharp edges dramatically reduces safety threshold against abnormal combustion.
If that's what it is, it's saveable. Gotta start with a better plan.
As stated, get some compressed air into the cyl. Might be time for a teardown.
Sorry, bud..not lookin' good.
 
Ok figured out the issue, the PCV valve was to restrictive that I was using, under hard throttle right at or close to full throttle when vac. Goes to 0 I was getting to much pressure an it would push the pressure an oil with it out the breather full tube. Used a high flow valve fixed the issue
 
Cool!
Except for the 1 bad hole. Might as well enjoy it for a while. :D
 
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