healeys
[Top] [All Lists]

100M crankcase vent

To: <healeys@autox.team.net>
Subject: 100M crankcase vent
From: "Allen C Miller, Jr." <acmiller@mhcable.com>
Date: Tue, 30 Aug 2005 09:40:33 -0400
I have been putting a lot of miles on the M this summer (two long driving
trips of ~750-1000 miles), and have been getting pretty trouble-free
performance. One of the minor problems I have is what appears to be oil loss
through the crankcase vent pipe attached to the tappet cover. There  is a
uniform deposit of oil mist on the inside of the left fender than seems to
center on the vent pipe, and I notice that the headers might create a larger
airflow obstruction than the original single pipe (the headers are Dennis
Welch Derrington style, but we customized the exhaust to run dual pipes from
the headers to a 6-cylinder two-in/ two-out muffler, so the pipe's tapered cut
stands over the inner pipe).

Is there a work-around for this? Would I be altering anything is I simply ran
a rubber hose from the down pipe to under the car to be in the 'slipstream'?

I also bought a 1" i.d. one-way rubber venting valve for oil covers which I
could also adapt to the pipe to keep the venting oil mist from aerosoling into
the engine compartment. It has a small back pressure, but operates effectively
as a one-way valve. Would there be any harm in this?

The oil loss is pretty significant (1 quart about every 500 miles), and there
is no oily soot in the exhaust, or any smoke even on start-up, so I think this
is the source of the loss. Is this amount of oil loss typical, or should I be
looking into the bottom end internals? I can live with this, but it is a pain
to wipe down the underside and fender's interior (chubby arms).

Any and all advice welcome.

Other than that, the M seemed to enjoy its last outing to New Hampshire's
scenic roads. Have a great Labor Day.

Allen Miller




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