spridgets
[Top] [All Lists]

Re: Crankcase Venting

To: VolksPEZ@aol.com
Subject: Re: Crankcase Venting
From: Ulix Goettsch <ulix@u.washington.edu>
Date: Tue, 1 Jun 1999 13:51:37 -0700 (PDT)
Cc: spridgets@autox.team.net
In-reply-to: <69fa681e.248495d2@aol.com>
Reply-to: Ulix Goettsch <ulix@u.washington.edu>
Sender: owner-spridgets@autox.team.net
Hi Jim (Mr. Carillo-rods-but-we-tight :-)

Why did you install a PCV valve?  You are not doing POSITIVE crankcase
venting by connecting manifold vacuum to the crankcase, you are just
venting to a catch tank. It should work even better
if you take out the valve, shouldn't it?
Also, I would assume that if you open up the little hole in the valve
cover vent tube all the way to the diameter of the tube, that should
provide enough pressure relief for the top end so that the oil wouldn't
come out of the cap.  Just a thought.

Ulix

On Mon, 31 May 1999 VolksPEZ@aol.com wrote:

> My biggest problem since putting the "Motor of Doom" in the Spridget (1380, 
> roller rockers, carrilo rods, JG pistons yada yada) has been excessive 
> crankcase pressure.  Venting from the front cover and the valve cover into a 
> catch tank (this is a race car) Still pressures high enough that the valve 
> cover gasket was not holding.  Finally broke down and tried a kit offered by 
> MiniMani (www.minimania.com) that attaches a baffled vent to the fuel pump 
> opening (assuming you arent using a manual fuel pump) very nicely machined 
> piece...tapped for a threaded pipe fitting to run a vent pipe.  The threading 
> works great with threaded PCV valves.  took all of about 15 minutes to 
> install.  Ran the car up to about 9500 rpms (it can turn over 12000)and no 
> leaks...lots of venting into the catch tank but no leaks.  And unlike my 
> other 2 vents (still connected but not working as hard) the baffling seems to 
> be keeping the oil in the engine and not filling the catch tank.  Still needs 
> to stand the test of a full race day but so far Im real happy.  Will let 
> everyone know the results after the next race but this may be an answer for 
> all those with high reving motors with excessive crankcase pressure.
> BTW...does anyone make an aftermarket oil filler cap for the valve cover that 
> ISNT vented....mine tended to spew oil all over the motor under the 
> pressures...I finally sealed the vent holes with RTV but was wondering if 
> there was something better... would like to spring for one of those pretty 
> finned aluminum jobs with a screw on cap but as we all know "We Tight"
> 
> Jim
> 

    Ulix                                       __/__,__      ___/__|__  
..............................................(_o____o_)....<_O_____O_/...
                                              '67 Sprite     '74 X1/9


<Prev in Thread] Current Thread [Next in Thread>