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Discussion Starter · #1 ·
getting tons of blow by coming out at the valve cover breather.... tried a few things, hasn't seemed to help.... making a big mess under the hood, what to do? (194 ci. six)

replaced the breather w/ a new one

pcv valve hooked up the rear port on the vavle cover and to base of carb, 4bbl holley (shake it and it rattles like it's still good, line is free of clogs also)

is there a different valve cover w/ a better baffle in it to look for? or were they all the same....

any thoughts?

I put a ton of miles on this car, freeway and street, averaging 18,000 a year since '02, looking for something that works, not a quick rigged up fix....
 

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An old school trick is to run a "road hose".

basically get a PCV breather that has no PCV valve and run a long hose to a good spot under your car for it to well... spit out on the road.

Not echo friendly at all but works.

Iv even seen people weld a nipple of sorts onto their exhaust to hook the hose to also.
 

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You didn't say type Or whos vlave cover you have on your motor. If there isn't a baffle under the oil breather, That is Your Main issue.The rockers are just tossing the oil right at the breather base.
 

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getting tons of blow by coming out at the valve cover breather.... tried a few things, hasn't seemed to help.... making a big mess under the hood, what to do? (194 ci. six)

replaced the breather w/ a new one

pcv valve hooked up the rear port on the vavle cover and to base of carb, 4bbl holley (shake it and it rattles like it's still good, line is free of clogs also)

is there a different valve cover w/ a better baffle in it to look for? or were they all the same....

any thoughts?

I put a ton of miles on this car, freeway and street, averaging 18,000 a year since '02, looking for something that works, not a quick rigged up fix....
The 'shake' test for checking a PCV valve doesn't work. It's a waste of time. All that will tell you is if it is completely filled with rust or crap to the point it should have been replaced 100,000 miles ago. The pintile inside the valve can still be clogged and it will pass the shake test. Go buy a new PCV valve first (they're dirt cheap) and see what happens. PCV valve should be replaced as often (or more often) than spark plugs. Every tune-up. They don't last long - especially on high-milage engines.

I replace my PCV valve every tune-up. It should be looked at like anything else that needs replaced frequently.
 

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Discussion Starter · #9 ·
thanks guys for the input....

going to pick up a new pcv valve..

also think the stock valve cover I'm running now has no baffle, I've got a couple other junk ones I can weld and hack on and make a baffle for it...I'll get on it this weekend.... see what happens...
 

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That is a very good point about the baffle. On my chevy 383, we installed old aluminum non-baffled covers. GAWD, they chewed oil to the tune of about a quart every few hard trips!!! Every time I'd go to high vacuum, poof, there goes blue smoke through the exhaust pipes. Pulled the covers off, screwed and siliconed the supplied baffles, and have never had an issue since, with no oil consumption like that!! Good point!!
 

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Discussion Starter · #11 ·
Update...

swapped out valve covers this weekend, the one on there only had a baffle on the pcv side, none on the front hole.... swapped it out w/ one I had w/ baffles on each hole....
(original one on bottom, new one on top)

also replaced the pcv valve w/ a new one...

appears to still be getting a lot of blow by at the breather, put about 70 miles on it today at work....(could have been residual oil that was allready in the breather)

My new question(s) is/are.... did this application originally come w/ a breather? and/or does this application need a breather?

I've read tons of threads on breathers and I know they are important, but the reason I ask this is I'm assuming by looking at the stock valve cover that it originally came w/ an oil cap only instead of a breather (this would explain not having a baffle on the front hole).
I really want to stop all the oil from crudding up everything....

thanks for any input....
 

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This could be as simple has having a bad or incorrect PCV valve. Just because it rattles does not make it a good unit.

The breather is there to take air in, if blow by is happening it is one of 2 problems.

First being, there is no air circulaton, PCV system is not correct.

Also, you can not over come Bad rings, bad valve guides.
 
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