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Author Topic:   Blowing oil out the breather
Dirt Forum Racer

Total posts: 94
posted April 17, 2005 04:05 PM  
The last two weekends the motor has been blowing oil out of the valve cover breather. About a quart for the night, roughly 30 laps. Any thought on what could be causing this, the motor has about 25 nights on it.


Dirt Forum Champ
Total posts: 968
posted April 17, 2005 06:12 PM  
Just guessing I wuld say that you have broken a piston or two.
That's what I found when mine did that...sorry to be the bearer of bad omens.

Mr. Badboy
Dirt Full Roller

Total posts: 29
posted April 17, 2005 06:43 PM  
Try running a compression check and leak down. This should give a good idea of the type of problem and which cylinder(s) the problem can be found.

Dirt Maniac

Total posts: 127
posted April 17, 2005 08:32 PM  
I am having the same prob and today was the 1st day out on a fresh engine any ideas

racing is way too cool gave up golf for it

Dirt Maniac

Total posts: 165
posted April 17, 2005 08:34 PM  
if u don't have oil restrictors it could just be getting to much oil and dosn't have anywere to go except out mine does the same thing half a quart a night just clean it up at the car wash and make sure u are full before u go out to race

Dirt Forum Racer

Total posts: 94
posted April 17, 2005 08:39 PM  
I am running restrictors. I would not ordinarilly be concerned but I did not have this happening last year or the first two weeks of this year.

[This message has been edited by sledgehammer (edited April 17, 2005).]

Dirt Maniac

Total posts: 123
posted April 17, 2005 09:13 PM  
i ran in to this promlem late last season and it was the rings allowing blow by. a re build cleared it up

Dirt Maniac

Total posts: 167
posted April 19, 2005 12:51 PM  
sounds like motor is ready to be freshened up.

Dirt Forum Racer

Total posts: 100
posted April 19, 2005 05:00 PM  
A quart for the night? That's alot. It's normal for some oil to come out the breathers but I dont know about that much. I cut up some pantyhose and stuff it into my breathers so the oil doesnt make a mess of my engine. Dont works good.

Dirt Forum Racer

Total posts: 94
posted April 19, 2005 05:30 PM  
I'll have to try that, here are the compression readings.


My first time doing this, but #7 is the only one that seems to be off much.

Dirt Freak

Total posts: 344
posted April 20, 2005 07:30 AM  
As long as they are all within 10% of each other it shouldn't be a problem.

Dirt Maniac

Total posts: 123
posted April 24, 2005 10:30 PM  
u say about panty hose i have a trick like that too but i use socks over the outside helps keep the dirt out of the filter and and oil off the engine. plus there easy to wash

Dirt Freak

Total posts: 372
posted April 25, 2005 03:28 PM  
i 2nd the sock idea, i usually cut'em in half, been doing that for 4 years now, it helps keep the bigger chunks outta the filters and helps everything stay cleaner, i usually change the socks every 3-4 weeks. my dog likes to chew on old socks so there is an overabundance of them around here,lol, you just gotta be quick and take e'm when he ain't looking, i tried taking one right away from him once and hefollowed me out into the shop and would'nt leave me alone till i gave it

Dirt Full Roller

Total posts: 26
posted April 25, 2005 08:12 PM  
I had that problem before. We put a Chrysler PCV valve on the valve cover, and got the vacuum off the carb. cured the problem right away, didnt need a rebuild like we feared.

Dirt Maniac

Total posts: 106
posted April 26, 2005 02:42 PM  
I had the same problem last year with a fresh engine. We put a splash guard in, and welded covers over the holes inside the valve cover. Dont plug it completly obviously, but we took and bent light metal so there is about a 1/4 inch opening 1/2 inch to either side of the vent hole.

Not one drop since.

Dirt Forum Racer

Total posts: 94
posted April 26, 2005 04:25 PM  
How much end gap did you have in the rings?

Dirt Forum Racer

Total posts: 94
posted April 26, 2005 05:11 PM  

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