Date: Mon, 13 Jun 2011 20:55:53 -0700
Reply-To: Poppie Jagersand <poppie.jagersand@YAHOO.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Poppie Jagersand <poppie.jagersand@YAHOO.CA>
Subject: Re: Debugging air leaks in a Diesel
In-Reply-To: <356474.42913.qm@web45303.mail.sp1.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Seem like the injection pump input shaft seal is the culprit as some suggested. Today I did some more testing running off using two hoses into a jerry can with Diesel. If the can is below the pump, small air bubbles are visible in the fuel return line as I wrote before. However putting the can a foot or two above the injection pump, and thus creating a small over pressure into the pump, then the bubbles go away. Instead a drop or two (very little) Diesel leaked out around the input shaft. I saw no other leaks.
This small air leak does not seem to affect driveability. It just takes a lot of cranking to start it. Bad for starter and pump! Doing the seal would be easy when time for the timing belt and tensioner change. Until then I'm tempted to put in an in-line fuel pump at the tank with a switch so I can prime the pump before starting.
Martin
--- On Mon, 6/13/11, Poppie Jagersand <poppie.jagersand@yahoo.ca> wrote:
> From: Poppie Jagersand <poppie.jagersand@yahoo.ca>
> Received: Monday, June 13, 2011, 1:18 AM
> Update on the slow progress on
> getting the Westy road ready. Our vacation got delayed a
> month so I have not been working on it at the speed I should
> have. Put in another afternoon in the debugging this
> Sunday.
>
> Looks like the unfortunate news is that the injection pump
> itself has a very small air leak. I have replaced all the
> rubber hoses for the injector return lines (the usual
> suspects). Then I disconnected the fuel; in and return lines
> on the pump and connected two new hoses that I ran directly
> from a jerry can of Diesel fuel.
>
> When starting the pump would first purge the air, so pushed
> big air bubbles through the return line. However, even after
> some minutes of running, small air bubbles would remain. I'm
> not sure how long it takes for the air to be completely
> purged, but it looked to me as if there was a continuing and
> not diminishing amount of small bubbles.
>
> So I'm running out of "easy" things to change. I guess I
> can change the copper washers on the input and output fuel
> fittings on the pump. If that doesn't help what else can I
> try short of removing the pump and replacing seals?
>
> I'm thinking since the bubbles continue when running, the
> leak should before the vane transfer pump. I'm not sure what
> shafts seals should be most suspect, but the input shaft
> might be one.
>
> Let me know what you think and if there is anything else I
> should test.
>
> I tried Gnarlie's oil squirting trick on the inlet
> fittings. Wasn't sure how to get motor oil to the input seal
> without risking splattering one the timing belt, so didn't
> do that. (Bad idea since backside of timing belt drives the
> intermediate shaft, and oil on the belt can make it slip.
> b.t.d.t. on my previous B2 Passat TD)
>
> I might also try adding a low pressure electric pump at the
> fuel tank as several forum members suggested. What do you
> think about this ebay pump?
> http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&item=220797730011&ssPageName=STRK:MEWAX:IT
>
> Thanks,
>
> Martin (and '82 Westy 1,9TD "Poppie")
>
| 
