[TR] Fw: TR4A Crankcase Breather Valve

Randall tr3driver at ca.rr.com
Wed Oct 21 22:40:36 MDT 2009


> Cosmo and i where chatting recently and we discovered we have 
> 2 similar but
> different parts.
> the manifold adapter (moss page 14 item #67) that Cosmo has
> is just a straight through tube, while mine is a spring 
> loaded one way valve.
> crank case gas can go into my manifold but not come out.

Should definitely be a check valve in there somewhere!  Otherwise, when you
floor the throttle, the partial vacuum in the crankcase is going to suck
fuel/air mixture out of the manifold.

But the information I have indicates that the check valve function was
incorporated in the PCV valve.  And the TR4A SPC lists the adapter as
Stanpart 138530, which is a simple straight-through adapter (also used for
the thermostat bypass on a TR6 apparently).
http://www.zeni.net/trf/TR6bluebook/76.php

So I think yours is a DPO-ism, Frank.

Randall


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