Date:         Sun, 15 May 2011 14:55:17 -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:      Debugging air leaks in a Diesel
Comments: To: Diesel-Vanagon@yahoogroups.com
In-Reply-To:  <iqp5c4+jgjs@eGroups.com>
Content-Type: text/plain; charset=us-ascii

The most common "hard start" problem I've had with both Diesel Vanagons and VW Diesel cars is a slow air leak allowing air into the injection pump that takes a lot of cranking to purge before it will start.

Culprits are often the injector fuel return lines. These are luckily easy to check. It is harder when it is in the return circuit to the tank. On my Quantum the return circuit was a combination of hose and tube. One tube in an inconvenient location roughly under the rear seat had rusted just enough to allow air in. Took me a lot of time to find.

Now my Vanagon Westy takes longer than usual to start. Pulled the small injection lines. Each shed a drop of fuel. Pulled the injector to pump line at the pump. That looked dry, but fuel hose is fine. (This one I replaced just last year) . Could be tank return line or some problem with pump.

Wanted to pull the plastic return line to tank, but it wont come off. In the past I've pulled it, cut a piece and put a fresh piece on the pump each time. Now I'm at/near the limit of length.

To get it back on I usually have to heat the plastic line with a lighter flame. That sometimes works, but sometimes melts it too much and I have to cut and start over. Is there a better way?

What do you suggest to do when the line becomes too short? Splice in a piece of hose? (add one more junction to leak...) Replace whole line? Can the original style plastic line still be bought somewhere? (I'd hate to have rubber hose all the way)

I had to replace the input line from fuel filter to injection pump a couple of years ago. Canadian dealer no longer has the clear line (where one supposedily can see any air bubbles). Just sold me black rubber hose at $20/metre.

Does anyone have a more principled approach to go about finding air leaks into the Diesel fuel system?

Martin (and '82 Westy 1.9TD "Poppie")