Too much Crankcase pressure
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Too much Crankcase pressure
I think, that I am getting too much Crankcase pressure on my new engine, (11.1 CR)
I notice a "mist" of oil escaping around the bottoms of the valve cover grommets, the PCV works,
when the car idles, it seems to leak only when I am using the mid to upper RPM range.
I wonder about the Charcoal canister, I wonder about putting a Breather in the valve covers.
Don't know, what have you guys done to alleviate this?
I notice a "mist" of oil escaping around the bottoms of the valve cover grommets, the PCV works,
when the car idles, it seems to leak only when I am using the mid to upper RPM range.
I wonder about the Charcoal canister, I wonder about putting a Breather in the valve covers.
Don't know, what have you guys done to alleviate this?
Burning Brakes
Joined: Jun 2002
Posts: 1,001
Likes: 1
From: sd
Don't do just the breather in the valve covers....ask me how I know and why I had to tear the whole front side of the motor apart to replace a leaking crank seal on a new 383. PCV is good! Don't pull it, you'll regret it. Sorry LD85 I don't have an answer on what is going to help with you're problem though.
Melting Slicks
Joined: Jun 2002
Posts: 2,151
Likes: 239
From: Northern VA
gosh Larry, wasn't this happening on the previous motor??? I am still having the exact same issues on mine. My leakdown test was ok but I am pulling a lot of oil thru the intake! I put a small inline catch on the PCV line and it fills pretty quick. I am at 11.8 CR
I really don't want to pull the motor as it is running really good
I really don't want to pull the motor as it is running really good
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by jerkyboy
gosh Larry, wasn't this happening on the previous motor??? I am still having the exact same issues on mine. My leakdown test was ok but I am pulling a lot of oil thru the intake! I put a small inline catch on the PCV line and it fills pretty quick. I am at 11.8 CR
I really don't want to pull the motor as it is running really good
I really don't want to pull the motor as it is running really good
I just got back into town, I am goiing to look it over this weekend, it just seems like it only leaks when I get it up in RPM's, I will get it on the ramps again tomorrow and check it over in depth this weekend.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Any chance the oil pump is putting out excess pressure?
Just throwing an idea up there,may not be related at all.
Hope you figure things out...when I get a chance to come to Indy,hopefully in a few weeks,ill get in touch and maybe come by!
Just throwing an idea up there,may not be related at all.
Hope you figure things out...when I get a chance to come to Indy,hopefully in a few weeks,ill get in touch and maybe come by!
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Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by Bill's86Coupe
Any chance the oil pump is putting out excess pressure?
Just throwing an idea up there,may not be related at all.
Hope you figure things out...when I get a chance to come to Indy,hopefully in a few weeks,ill get in touch and maybe come by!
Just throwing an idea up there,may not be related at all.
Hope you figure things out...when I get a chance to come to Indy,hopefully in a few weeks,ill get in touch and maybe come by!
Hey Bill, it might be, it is a HV oil pump, I will know more tomorrow, I hope
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
OK, I found a couple of things,
the fancy Billet Breather caps I bought have a smaller orifice tube OD
(7/16" ) , than the factory fittings, so I put the factory breather parts back on with the larger (.5/8") hose and also the factory PCV valve which appears to have a much lighter duty spring.
the rear of the valve covers are still leaking but,, the good news is that there is no noticeable crankcase pressure coming from the VC's
I will wipe it down Saturday and pull the VC's again
the fancy Billet Breather caps I bought have a smaller orifice tube OD
(7/16" ) , than the factory fittings, so I put the factory breather parts back on with the larger (.5/8") hose and also the factory PCV valve which appears to have a much lighter duty spring.
the rear of the valve covers are still leaking but,, the good news is that there is no noticeable crankcase pressure coming from the VC's
I will wipe it down Saturday and pull the VC's again
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by honda hunter
Could you get some different valve covers and a new gasket to see if it still does it?
I will get new gaskets in the morning and take this new rubber set back to Autozone, they are junk, and I will likley by a new set of VC's too,
Race Director
Joined: Aug 2000
Posts: 14,130
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Cruise-In II Veteran
Hey Buddy,hope you got it figured out! Btw,I was just bored and wondering,have you hooked up a vacuum pump/gauge to the engine?
If so whats the reading?Im just curious thats all.Was wondering what the inches of vac would be on an engine like yours normally put out.
Keep us posted on your progress!
If so whats the reading?Im just curious thats all.Was wondering what the inches of vac would be on an engine like yours normally put out.
Keep us posted on your progress!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
OK, it was a combination of rear passenger valve cover leak and an rear of the intake leak. I am a little surprised because I gooped the heck out of the china wall with right stuff, but, this is better than a rear main leak in my book.
No more misting around the valve cover grommets so going to the larger ID hose/breather fitting helped this scenario.
Bill, 42cm/hg at idle, drops to 10 or so when you blip the throttle
No more misting around the valve cover grommets so going to the larger ID hose/breather fitting helped this scenario.
Bill, 42cm/hg at idle, drops to 10 or so when you blip the throttle
Last edited by LD85; Aug 19, 2006 at 04:53 PM.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Originally Posted by LD85
OK, it was a combination of rear passenger valve cover leak and an rear of the intake leak. I am a little surprised because I gooped the heck out of the china wall with right stuff, but, this is better than a rear main leak in my book.
No more misting around the valve cover grommets so going to the larger ID hose/breather fitting helped this scenario.
Bill, 42cm/hg at idle, drops to 10 or so when you blip the throttle
No more misting around the valve cover grommets so going to the larger ID hose/breather fitting helped this scenario.
Bill, 42cm/hg at idle, drops to 10 or so when you blip the throttle
