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(75 280) Valve Cover Breather Hose replacement


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So I need a new valve cover breather hose since it has split where it connects to the Valve cover.... I can't seem to find a part number for it and the one I could find is from MSA 

 

http://www.thezstore.com/page/TZS/PROD/15-6204

 

but it says that hose is for 77-78 280zs

 

Also when I pulled the hose off there was some brownish black goop inside the hose... is that normal??

 

 

Edit: Also the PVC valve on the crank case doesn't tighten down all the way in the right placement... When it is tighten down the hose can't reach it and it looks like this

 

7e1j24R.jpg

Edited by Zmanj87
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It's just a piece of hose. I believe it's something like 9/16 ID hose. You can buy it by the foot at Autozone etc.  All it does is connect the crankcase back to the intake to reburn some of the fumes that leak past the cylinders.  Some people just put an air filer on it and leave it. I believe running it back into the intake is best.  Clocker is right, you're not looking at a PCV valve, that's just a hose barb. The goo inside is oil that's blown out of the valve cover. It's no big deal, it's too little to be of importance. It san be hard on your seals if that gets pinched off.   The L28 and the L24/L26 are mostly the same engine, the biggest difference is that most L28's were fuel injected.

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How you deal with this system depends entirely on whether you have carbs or FI.

 

With carbs you can do pretty much anything you want- put filters on the valve cover and block, put catchcans, run it stock...the carbs don't much care.

EFI is another matter.

 

If you look at the FSM, you'll see the valve cover is an intake, not a breather.

It is fed air sourced after the AFM and before the throttle plate.

This air is pumped through the crankcase and reintroduced into the intake through the PCV valve under the intake manifold.

 

This is important because the computer is aware of this extra air coming into the intake...it's already been seen by the AFM.

Putting a filter on the valve cover is just a giant vac leak into the intake.

 

In theory, at least.

I've seen pics of injected cars with just a filter, with the valve cover plumbed direct into the intake manifold, with catch cans, etc., and the odd thing is that they all claim to work great.

 

Perhaps our computers are just too crude to know?

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The mess inside the hose is the  " back fire " something to prevent oil goes in. Last time when I changed all my hose , I thought some stupid mechanic clean the hose and left stuff in there. I found that out later after threw the whole thing away and change the new hose from O'reilly. I didn't stuck any stainless steel mess in there, however , I checked the hose every couple oil change seeing it was clean inside without oil.

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The hose from the valve cover is part of the PCV system.  The L shaped metal fitting from the top of the cover is just a press fit with adhesive in to a grommet, I believe, or something similar.  It's not threaded.  You have to seal that if you're running EFI.  If your engine runs clean you can get away with heater hose for the valve cover hose.  It only sees fumes if you have more blowby than the PCV valve and its hose underneath the manifold can handle.  The flame arrester is an individual call.  A piece of brass scrubbing pad would probably do the same job.  I think it only sees flame in extreme cases.

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In to a plastic grommet?  With adhesive?  I think it's meant for permanent installation with no rotation.  At least on the 280Z and ZX covers I've seen. 

 

In other words, he can spin it all he wants, it's not going to get tighter.  The plastic base is broken.

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