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Re: 1500 Blowing Oil

To: Michael Altomare <MTAltomare@prodigy.net>
Subject: Re: 1500 Blowing Oil
From: Joe Curry <spitlist@gte.net>
Date: Sun, 14 Feb 1999 12:03:40 -0800
Michael,
Since the 1500's were designed to be a "closed" breathing system, the
air pump in integral to relieving the pressures built up in the sump. 
My first experience with this problem was on my brother's '68 Camaro
that he purchased new.  After removing the air pump, he couldn't keep
oil in it. (Unfortunately my younger brother took a hammer to it and
rendered it useless to re-install)

So if the emissions equipment is removed, one must try to re-create the
"open" breathing system first implemented on the Spitfires on the Mk1. 
It consists of a blow-by pipe on the right side of the engine and a
valve cover that had no breather pipe.  If you look closely you will see
the hump on the 1500 that is the remnant of the casting for the blow-by
pipe.  You could carefully drill that out (but only when the block id
disassembled), or use the hole provided by the fuel pump as Kas Kastner
suggests.  When I first did that, I hadn't read Kastner's book, so I
thought It was an "original" idea.  Just shows what I know!

It's a good idea to use all available relief holes to solve the problem,
so I connected the valve cover breather tube through a "T" to the hose
from the fuel pump port.  Then I routed it to a catch bottle to prevent
any oil from escaping.  So far I haven't collected any oil in the
bottle, so it must be working.

Regards,
Joe

Michael Altomare wrote:
> 
> HI, I'm pretty new to the reader's list, and thought that this subject was
> pretty interesting.  I've had my '77 1500 since 1981, and never had a
> problem with blowing oil until I rebuilt the engine last year.  I used high
> compression pistons, Kent cam, Weber 32/36 carb and a Mallory Unilite
> distributor.  It runs great except for too high an idle speed and oil that
> blows out of the dipstick and valve cover vent.  The oil will pool up in the
> air cleaner assembly after a short period of time.  It doesn't get into the
> carb as the Weber's inlet  has a raised area that blocks it.  I assumed that
> I had excessive blowby that will go away after the rings seat, but after 700
> miles, it hasn't.  I do have an electric fuel pump that I added as a boost
> pump for the mechanical pump, so I could use the mechanical pump's mounting
> pad as described in Joe's article.  As Bob asked, what else could/should be
> done?  I'm also unclear on how the emissions equipment (when it was
> installed) kept the oil from blowing - the pressure has to vent somewhere.
> Please explain.

-- 
"If you can't excel with talent, triumph with effort."
 -- Dave Weinbaum in National Enquirer



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