Date: Thu, 1 Sep 2005 13:43:10 -0500
Reply-To: Stan Wilder <wilden1-1@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1-1@SBCGLOBAL.NET>
Subject: Re: oil from pushrod tubes
Content-Type: text/plain; charset="iso-8859-1"
There is more to pushrod tubes than just push rod tubes.
There are O rings on each end.
The smaller inner O ring usually drops right in to the crankcase bore
provided.
The outer smaller O ring requires some message to get it to slide in through
the top of the hole provided in the head.
The hole has a slight shoulder that often cuts O rings for novice
installers.
It's a good idea to clean the crankcase and head bores and use a good
silicone coating for insurance on the O rings.
In addition there are wire retainers inside the valve cover area that hold
the pushrod tubes in the right position.
If this wire retainer slips off the edge of the push rod tube it can drag on
the pushrod and eventually cause a problem by allowing the tube to move or
it could cut a hole in the pushrod within 50 years.
That's the tube part, now on to the valve cover bails. The bails are the
wire retainers on the heads that hold the valve covers tight to the head.
Loose bails will often allow leaks past the valve cover gaskets.
You can re-bend them to get a tighter fit.
The mostly Cork gaskets appear to work better than the other options.
If oil is everywhere like you say it could also be coming from a loose fit
at the steel tube at the oil fill tube. Heat distorts the plastic parts and
they will leak if you have overfilled the crankcase or have just minor
crankcase pressure.
If you have been blowing the dipstick out of the tube about an inch I'd
suspect that you have crankcase pressure from a broken ring.
If you've sprayed lots of oil it can often get picked up by the engine can
and hold in the bottom of the fan shroud for easy distribution later. Be
sure the fan shroud gets cleaned too and has a drain to let the extra oil
out.
Stan Wilder
Engine Ceramics
214-352-4931
www.engineceramics.com
----- Original Message -----
From: "Alan Sinclair" <alan@DETERMINISTICNETWORKS.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, September 01, 2005 1:04 PM
Subject: oil from pushrod tubes
> First the history: last week our '81 a/c tanagon got new hydraulic
> lifters fitted at a local shop, then went to a different place for a
> transmission checkup. At the tranny shop, with the van on the lift,
> there was a largish pool of oil on the floor, looking like it came from
> the pushrod tubes above the heat exchanger. Back to the local shop,
> arriving in a BIG cloud of oil smoke (outside and inside from the
> heater), who said the rocker cover had been leaking and they fixed it
> (free.)
>
> Now the problem: picked up the tanagon and drove home late, last bit is
> a very steep 100 ft driveway. At the top, another cloud of smoke and a
> cupful of oil on the ground. Could this oil have been sitting somewhere
> inside the engine, draining out (over the heat exchanger) only when I
> drove up our steep driveway? Otherwise the leak must have sprung again.
>
> The van is back at the local shop, who are checking again, but say
> there's so much oil it needs steam cleaning before they can tell much.
> That's not possible before the long weekend so any insights would be
> helpful. My other car has just split its radiator so maybe the weekend
> will all be walking.
>
> I should be under the van myself, but work's getting in the way (and I
> don't have risers or a lift.)
> Thanks
> Alan
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