Date:         Fri, 12 Oct 2001 12:45:23 -0700
Reply-To:     Tobin Copley <tobin.copley@UBC.CA>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Tobin Copley <tobin.copley@UBC.CA>
Subject:      Fixed!: How the heck to prime oil pump? (Vanagon D)
In-Reply-To:  <3B3F3C2C.837A6B4B@pugetsound.net>
Content-Type: text/plain; charset="us-ascii" ; format="flowed"

Hi all,

Some of you many remember me pulling my hair out over the oil pump in
my 1.6L diesel Vanagon initially having, but then permanently losing,
the ability to establish prime.  Well, it appears I have resolved the
problem.

For a full description of the history behind the problem, my efforts
to fix it, and quite a few pictures of the pump, my fix, and the
badly worn #3 rod bearings that precipitated the whole thing, please
go to:

http://www.sfu.ca/~tcopley/vw/ and click on the "oil pump" link at the top.

The oil pressure relief valve in the oil pump pickup tube was indeed
stuck in its bore. Thanks to the many vanagon list members who
provided feedback on the pictures and commentary posted here, and for
their helpful feedback and suggestions.

Very special thanks are due to Bob Donalds of Boston Engine ("Boston
Bob") for his extraordinary help and invaluable advice. Bob contacted
me following my initial post about the "no prime" problem, and asked
me to phone him so we could talk about it. He provided excellent
feedback, and personally spent over 25 minutes on the phone with
me--free of charge!  What a guy!  So thanks, Bob!

The oil pressure relief valve was indeed stuck partly open, with the
result being that the oil pump was sucking air instead of oil. I'm
very glad I tested the engine's lubrication system by spinning the
oil pump shaft with an electric drill first. Starting an engine with
such a serious problem would have almost certainly quickly led to
engine damage.

Following Boston Bob's suggestion, I dremelled out the metal holding
the oil pressure relief valve's cap in place, then removed the cap
and spring. The piston proved to be very difficult to remove from the
bore, as it was very soundly seized in place by grit and the remains
of my toasted bearings (see my web page for gory wasted bearing
pics). A coat hanger and various pokey and prying tools were used to
force the piston out of the bore. This was quite difficult to do,
since I had to be careful not to mangle the soft aluminum body of the
pickup tube itself when doing this.

With the oil pressure relief valve disassembled, I cleaned up the
piston with OO steel wool. I used a chainsaw file to remove the worst
of the burrs and nicks from the cylinder bore, then did a sloppy very
jury-rigged honing job on it using a chopstick and more OO steel
wool. And a lot of time.

It turns out I had removed far too much material from the pickup tube
body with the dremel, leaving me with too little metal on the body
left to stake the oil pressure relief valve's cap back in place.
Ooops.  Improvising, I drilled a 1/16" hole through each side of the
oil pickup tube body, with the hole passing through the cap as well.
Through these holes I fit a small cotter pin, thus holding the cap in
place against the oil pressure relief valve spring tension.

The correct method of dealing with this problem is, of course to buy
a new oil pickup tube. But I didn't have the funds to do this, and I
was treating the whole exercise as an educational experience anyway.
I'm leaning towards removing the diesel power plant and installing an
I-4 gasoline powered engine, and if I go this route I'd spring for a
new oil pump and pickup tube. I wish I had the coin to do a TDI
conversion, but that's just not going to happen.

I was expecting hear serious rod knock once I got the engine started
up, but with 20 minutes or so of idling and revving for warmup (to
permit changing the oil out), I didn't hear anything unusual. The
normal diesel valve train clatter may have been drowning rod knock
out, but I doubt it. Maybe I'll hear it when I actually try driving
it and load the drive train a bit--we'll see. Before I do that,
though, I'll be installing a oil pressure sender and gauge, and I'll
need a new battery.  So I won't know until spring when I take
"Stinky" out of winter mothballs.

Thanks again to everyone for their feedback and help in trying to
solve my oil pump priming problem!

T.
--
-------------------------------------------------------------------------
Tobin Copley        Bowen Island, BC, Canada      49deg 23'N-123deg 19'W

'82 Westfalia 1.6L NA diesel ("Stinky")
'97 son Russell                                   =============
'99 daughter Margaret                            /_| |_L| |__|:| clatter
                             SPEED KILLS!        {.            .| clatter!
                         Drive a Vanagon diesel   ~-()-==----()-~