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TR4/4A PCV hoses

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nbailey

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I recently noticed more oil leaks and consumption on my 4A. I just noticed that the PCV hoses I
had purchased from Moss collapse when engine running. They are made from soft rubber, and can,t
handle the vacuum. Has anyone found a supplier that has hoses that work properly? Thanks for any help.
 
I'm not sure what size your 4A takes; but any decent auto parts store should have PCV hose in several sizes and sold by the inch. In addition to withstanding vacuum, it has to be resistant to oil vapor, which many hoses are not. In the past, I've "made do" with heater hose, but it turns to mush after a few years of service.
 
To prevent hoses from collapsing there is an additional step you can take. Remove the hose from the car and measure its inside diameter. At the hardware store buy a length of screen door closure spring that will fit inside the hose. I typically pull the spring open to deform it so adjacent coils are not directly touching each other. Then measure the spring and cut a length that is shorter than the hose by the length of the nipples it slips onto. Insert the spring in the hose, refit to the car, and you have a hose that will not collapse again.
 
nbailey said:
I recently noticed more oil leaks and consumption on my 4A. I just noticed that the PCV hoses I
had purchased from Moss collapse when engine running. They are made from soft rubber, and can,t
handle the vacuum. Has anyone found a supplier that has hoses that work properly? Thanks for any help.
Click to expand...

Can you tell me what part number you purchased and from what vendor, if it wasn't us, so I can track this down. PCV hose should not collapse. I need to get our Tech department on this.

Thanks,

Shawn
PS You can also email me at shawn@mossmotors.com
 
Nbailey,

How did you actually trace it back to collapsing hoses? This may be the answer I have been desperate to find.

I replaced my PCV hoses in summer 2000. All seemed good until about 2008 when my car started suffering very bad crankcase pressurization and oil leaks pretty much from every opening. At it's worst I was getting oil coming out the oil filler cap on the valve cover and a 4" puddle of oil on the floor an hour after a drive. I tried everything...leak down tests, compression tests, rebuilt/reconfigured my original PCV, purchased new PCV, purchased NOS PCV from ebay...on and on and on. For 2 years I was pulling my hair out and going insane. I finally admitted I couldn't solve the issue (attributing it to a faulty PCV design from the factory). I resolved to simply run a 1/2" hose of the valve cover, over the carbs routed down by the chassis - effectively making a mini road draft tube. It seems to vent well enough.

But, your post may have given me something new to inspect! Can't wait to wake the car from its winter slumber and look at those hoses. Who knows?

Bob
 
Responding to my own response. I pulled my PCV from the basement and inspected the hoses. They are much more rigid/firm than I expected - not soft or pliable at all. So, it is unlikely they were collapsing under vacuum. I'm somewhat disappointed - since I was hoping this would be a quick easy fixed to my problem.

I'll still inspect more fully on a running engine when the car comes out of storage in April.

Bob
 
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