Jump to content

Fuel pump going out?


Guest Anonymous
 Share

Recommended Posts

Guest Anonymous

On the way back from a trip yesterday, I began to notice a growling/moaning noise coming from the engine, louder at higher rpms but not clearly rhythmically tied to engine or road speed. I have traced the sound to the valve cover in the region of the fuel pump pushrod. The fuel pump is leaking a fluid (uncertain as yet if it's fuel or oil) from the shaft running crosswise through the pump's "neck." I believe this is also the source of new leakage onto the engine block from the fuel-pump base.

Suggestions? Broken diaphragm, perhaps? How likely is whatever this is to do harm to the engine while driving the car -- could gas mix with the oil in the engine? Will this fail and strand me soon?

If it's the pump, I have a new later-style pump, but I know I'd need a different pushrod for it. I also understand a VW bug pump rebuild kit will work, if I can find one of them.

Thanks!

-Dave

Colorado '71

Link to comment
Share on other sites

Guest Anonymous

The pumps can leak where the pump valve is pressed onto the mounting flange - can mean a leaky diaphragm. The later pumps are the way to go - Much quieter. I wouldn't waste time trying to rebuild it when you can stick a new one on in 15 minutes. Stick a new inline fuel filter on too, and use new clamps and fuel hose if you're uncertain about the exisiting. I found that I didn't need the new pump rod - it was the same length as the one on the car, but I used since I bought it.

Link to comment
Share on other sites

Guest Anonymous

If you have the old style (i.e. rebuildable) fuel pump, replacing it with a new, later style (sealed) pump will require a new pushrod and spacer (insulator) block--later rod is a different length and spacer is a different thickness.

BTW--most mechanical fuel pumps eventually leak around the cross shaft--steel shaft on a pot metal journal=wear.

Cheers

Mike

A leaking fuel pump diaphragm will allow fuel to leak into the engine, thus diluting oil. Won't take much to mess up your bearings--happened to my Mom's Caprice and required new main, rod and cam bearings...

Pull old pump and check the pad on the pump where the pushrod bears. High mileage ones can wear to the point where the pushrod will no longer cause the pump to make a full stroke. If the rod has a flat spot worn on it, sometimes turning it around will at least get you going temporarily. If you can find a rebuild kit (from an old VW Beetle) the early style pumps are easy to rebuild--30 minute job.

Link to comment
Share on other sites

Guest Anonymous

Well, I tok the old pump off last night just to see if by chance my new sealed pump would fit. As Mike said, it would use a shorter pushrod. So I disassembled my old pump to see if it was FUBAR. I couldn't find anything clearly wrong -- no torn diaphragm or anything. So I cleaned it up really well and bolted it all back together. Doesn't seem to be leaking now (though it may still be around the shaft as Mike mentioned -- it was oil, not fuel), and the car runs fine.

Mike, any ideas on a source for the VW pump rebuild kit? Didn't see much on a quick perusal of the web yesterday.

The noise? Doing all this didn't help that, and more careful listening places it under the valve cover. My guess is the valves need some adjusting; the last time a few months ago was my first time, so they may not have been spot-on. I'll get 'em into spec once I have a chance and will post if that clears things up.

Thanks for your help!

-Dave

Link to comment
Share on other sites

Guest Anonymous

This is the same basic pump as used on VW beetles from the 50s and 60s...I have an old VW part number somewhere, but it's probably been superceded. Anyway, I don't think the part's available from VW any more. You need to find a place that sells vintage VW stuff, eihter on the web or find a copy of "Hot VWs" magazine and peruse the ads.

I've made new fuel pump diaphragms before from neoprene-reinforced fabric (available from a rubber supplier) to rebuild pumps where kits were just not available...but I'm sure these are--somewhere...

Good luck

Mike

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Upcoming Events

×
×
  • Create New...