C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

What Causes High Pressure in Crankcase?

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Old Sep 16, 2014 | 06:38 PM
  #21  
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Really TOM400CFI, Really. Why am I being Irresponsible??

You said-

Quote:
Originally Posted by cudamax View Post
Without a pcv on an engine or if its plugged You loose ring seal and horsepower.

TOM400CFI Replied-- No. There is still a crank case vent and that is sufficient to allow gases to escape on any reasonably sealed engine. No meaningful HP loss will occur from a plugged PCV valve. In fact, most racing applications don't have a PCV valve at all.

So you have your PCV Valve plugged and by-passed and are not running one on your engine because its not needed?? Because thats what you seem to be saying by overcorrecting my writings and you are Implying that here. That everyone doesn't need their's and that all the Auto engines and Auto Manufacturers really are wrong and can learn from you, that no one really needs a PCV valve and the Crankcase vent is good enough.

You are saying that I'm Irresponsible because of my Arm-Chair Diagnosis of the op's engine as being "Done" and should be rebuilt and or replaced because his motor is pushing oil while running out the dipstick tube and most likely pushing the dipstick itself up and pushing oil out the rocker arm oil filler cap and most likely will be blowing every seal on the engine and will be leaking from everywhere from Piston Combustion Ring Blow-by.

So according to you, whats right is wrong and whats wrong is right.
You know. This reminds me of a Crazy Ex-girlfriend I once had. Man she was Annoying and Funny at the same time and always Hormonal. My God What a Drama Queen She was.
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Old Sep 16, 2014 | 07:28 PM
  #22  
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CUDAMAX...you are CORRECT....in my opinion on what you wrote so far.

It is simple as this...as stated before....of you have verified that the PVC is sucking like crazy as designed....and you remove the tube int eh valve cover WITH the PCV in the valve cover on the other side...if you feel or see air/smoke coming out of the grommet in your valve cover...YOUR ENGINE IS SHOT.....Simple as that.

And CUDAMAX was using the air cleaners on engines with a carburetor ...where oil can collect up in them when there is a blow-by issue that is severe.

All I will write is this....if the PCV is sucking very strong...and I can feel air coming OUT of the fresh air tube grommet....it is POINTLESS for me to do anything else or any other test....because if the PCV can NOT keep up with the compression blow-by....then the rings are shot. Then in many cases..(pre-1984) I can stop the engine... and by pulling on the alternator belt..can spin the engine with NO effort...thus NO ring drag...thus worn out engine. I have had engines that when the breathers were taken out of the valve covers...it literally blew smoke rings out of the valve cover grommets that were blueish /white smoke.

MY vote it the rings are shot...and that is that...in my opinion....due to the information currently provided.

DUB
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Old Sep 16, 2014 | 07:56 PM
  #23  
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Thanxs DUB
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Old Sep 16, 2014 | 08:00 PM
  #24  
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Soes the OP know if his PCV is "sucking hard"??

Does he know his leak down? No. He doesn't. THat's why its irresponsible "advice".
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Old Sep 16, 2014 | 08:41 PM
  #25  
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My Arm Chair Diagnosis is by no means Irresponsible. He spoke of someone Ruining his engine. So I assumed that this was not going on for him in the past and had not happened slowly and over time. That would Indicate to me just a high milage worn motor

but by the op stating Detonation & overheating I suspect broken piston lan grooves and or piston rings and damaged and or wiped out cyl bores.

I'm sick and tired of defending myself and my writings and responses from what seems to be "My Weirdo Stalker" TOM400CFI whom is relentlessly personally attacking me and continues to contradict a lot of what I say.

I enjoy helping others with fixing their cars with advise from my life long obsession of building and repairing cars through my over 40yrs experience as a master mechanic.

I will not sit back Idle while someone wants to go on and on with me jumping from thread to thread and starting crap and stating that I have any Irresponsible or Malicious intent in my responses to mislead anyone in anyway.
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Old Sep 16, 2014 | 09:51 PM
  #26  
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Well finally making headway. Dealer agrees the oil blow by must be a piston/cylinder problem not the exhaust valve. We worked out a solution can cost me a few $$ if this is not the problem after engine tear down at his expense. This is good, more to follow.
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Old Sep 16, 2014 | 11:19 PM
  #27  
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Originally Posted by cudamax
So I assumed...
And therein is the root cause or your irresponsible advice-giving. We have figured it out. You made an assumption, advised a new motor w/out even confirming the hypothesis the OP's mechanic, came up with. A motor is a lot of money, to not even check and confirm the root cause of the problem.


Originally Posted by cudamax
I'm sick and tired of defending myself and my writings and responses from what seems to be "My Weirdo Stalker" TOM400CFI whom is relentlessly personally attacking me and continues to contradict a lot of what I say.
I asked in another thread, I'll try again here:
QUOTE WHERE I MADE A PERSONAL ATTACK. Did you not compare ME, to a "crazy x GF" above? A "drama queen"? QUOTE ME, where I ever said anything remotely that personal or attacking toward you. Who is making personal attacks here?In the other thread, it was YOU, who attacked ME, for stating fact, that you didn't happen to LIKE. You should educate yourself as to what a "personal attack" actually is, then you can stop doing it. *I* am sick of YOU attacking me for stating a fact, and correcting misinformation, or bogus claims. I left the last bogus claim in the other thread alone, just so as not to hurt your feelings...even though it was wrong, as wrong can be.



Originally Posted by cudamax
I enjoy helping others with fixing their cars with advise from my life long obsession of building and repairing cars through my over 40yrs experience as a master mechanic.
Great, so do I. I base my advice on fact, and PROVING parts to work or not work, however...not just WAG'ing and spending other peoples money on "arm chair assumptions".





At least the OP seems to have a solution worked out for himself.

Last edited by Tom400CFI; Sep 16, 2014 at 11:25 PM.
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Old Sep 16, 2014 | 11:30 PM
  #28  
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YA O.K Who is Proving now
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Old Sep 17, 2014 | 12:05 AM
  #29  
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Default Leak down!

Instead of making assumptions, just do a leak down and you will know WITH OUT A DOUBT what is wrong with your engine. It's a quick easy test. Takes 2 hours tops.
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Old Sep 17, 2014 | 12:58 AM
  #30  
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It's in the Chevy Manual. Whenever while the motor is running and the engine oil dip stick pushes up on its own and oil starts to leak out of the dip stick tube.
1. Don't listen to anyone call Tommy
2. #1. above is a cry baby.
3. Replace Engine Block/Pistons & Rings.
4. Make whomever did this to the engine & Tommy Pay for it.
5. Thank Cudamax for being right all the Time.
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Old Sep 17, 2014 | 01:03 AM
  #31  
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Originally Posted by cudamax
It's in the Chevy Manual. Whenever while the motor is running and the engine oil dip stick pushes up on its own and oil starts to leak out of the dip stick tube.
1. Don't listen to anyone call Tommy
2. #1. above is a cry baby.
3. Replace Engine Block/Pistons & Rings.
4. Make whomever did this to the engine & Tommy Pay for it.
5. Thank Cudamax for being right all the Time.
CUDAMAX- are you drunk??
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Old Sep 17, 2014 | 01:15 AM
  #32  
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No Cudamax is Crashed out. This is Vanessa
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Old Sep 17, 2014 | 01:18 AM
  #33  
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Originally Posted by cudamax
No Cudamax is Crashed out. This is Vanessa
You can be anything you wanna be on the internet these days, even if that means you want to be a chick with the name Vanessa!
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Old Sep 17, 2014 | 02:39 AM
  #34  
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Default Vanessa??? :) Welcome to Corvette Forum!

Originally Posted by cudamax
No Cudamax is Crashed out. This is Vanessa
Cool. Hi Vanessa! Welcome to CF. You could have some real fun with Cudamax's account before you log out.

You could:
1. change his Avatar (I suggest a demure picture of yourself, G Rated please (OK, PG then)),

2. Post something in all of the open topics like "I am so sorry for being WRONG all the time"

3. Post "Tom is right -- AGAIN" in all the open topics

4. THEN, go back and post "Oops, I thought I was wrong but I made a mistake and I really am right" in all the open topics.

Then, when Cudamax logs in again in a few days, he will see a whole bunch of very confused posts about is he right or is he wrong....

Of course, you would have to be watching to get the full effect as he scrolls through the barrage of PMs and replies that will be waiting for him.

Could be rather amusing.....

Frankly, I don't know enough about engines to contribute anything complicated, but I am a trouble maker myself. I can do that pretty well.

Cheers,
M
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Old Sep 17, 2014 | 08:40 AM
  #35  
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Funny but that would never happen, Masterspy, even thou she's still pissed I sold the Cuda. She was tempted. Im glad all were nice to the boss.

Last edited by cudamax; Sep 17, 2014 at 08:43 AM.
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Old Sep 17, 2014 | 11:21 AM
  #36  
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My advice... If you are at a dealer.. drug stores should sell some lube or go to a xxx shoppe and by some **** lube you'll need it.
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Old Sep 17, 2014 | 02:54 PM
  #37  
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Originally Posted by Tom's '07 Monty
My 1990 L98 (101K miles) is now running fine but my trusted Corvette mechanic reports that my oil leaks are really "oil blow by" coming out of the oil dipstick tube and rocker arm cover oil filler cap. The oil is burning on the exhaust manifold. Mechanic reports that because of the recent overheating and severe denotation, a ring land or ring broke and/or a piston is burnt - both allowing the combustion chamber pressure to be released into the crankcase. The dealership that worked on the Vette originally (and whom is responsible for the overheating and denotation) says it a value not properly seating and now wants me to pay for a valve job. I have a hard time believing and my trusted mechanic says it is not the cause that a leaky value will cause this much pressure and blowby - especially for the oil coming out of the dipstick tube.

Advice please. thanks,

Tom
Sounds to me like you definately have a ring problem. All motor leak past the rings some, but of your blowing oil out the DS tube there are issues. As mentioned a leak down would tell, but they are a PITA Ill tell you right up front especially with the stock manifolds.

On the valve issue I will also tell you I just had a broken VS. When I pulled my plenum I immediately knew something was wrong. It was gas soaked and "cruddy" looking. I have nothing but air going in mine and fuel down the runners so it usually is prefectly clean. Not the case this time.

Upon investigating I had two intake valves broken which were allowing pressures to be pushed back into the intake. This could in the right situation make its way back through breather lines and into the crank. If that path exists.

Now I think you have bad rings and your in need of an overhaul. Welcome to the game and once the PITA part of paying the bills and getting it back together - you will be much happier with the new found power. Might as well stroke it while your in there.
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Old Sep 17, 2014 | 02:56 PM
  #38  
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You never told us how the dealer caused your overheating problem that caused the rings to go bad.
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