AC Delco Mechanical Fuel Pump

Joined
10 Jan 2017
Messages
1,821
Reaction score
279
Location
Derbyshire
Country
United Kingdom
I am suffering from fuel drain back to the tank on an older car which uses a mechanical fuel pump, it's the glass bowl type one as seen in the attached image. Fuel is also leaking into the oil through the diaphragm, so the whole thing needs refurbing.

The car is used weekly and each Friday the fuel has drained back to the tank, which makes it a pain starting as there's no manual lift pump (primer). I don't mind cranking a bit to build up oil pressure, but sitting there 10-20 seconds is causing premature wear on the battery and starter each week.

I have decided to rebuild the pump which should be fairly straightforward, however I'm not sure how to get the check valves out of the pump housing. They are apparently 'peened' into place using a suitably-sized socket and then a punch to bend metal over the top of them to hold them in place.

How would I go about 'un-peening' them and then 're-peening' them into place? Anybody here still know how to maintain these? Annoyingly, the later pumps (with a the manual primer) used a plate held in with screws to secure these valves which would be much easier!
 

Attachments

  • 1502406301_525046013.jpg
    1502406301_525046013.jpg
    129.3 KB · Views: 74
  • IMG_4919.jpg
    IMG_4919.jpg
    279.6 KB · Views: 77
How would I go about 'un-peening' them and then 're-peening' them into place? Anybody here still know how to maintain these? Annoyingly, the later pumps (with a the manual primer) used a plate held in with screws to secure these valves which would be much easier!

I'm not sure it would be any help to you, if you could get those valves out - you will not be able to repair/service those, or buy replacements. I half remember replacing those valves on one where they were not peened in place. I think your only way forward, is to seek a complete replacement.
 
Aha, traditional engineering :love:
The best way to remove peins is to grind them away - with great care! Out with the Dremel.
If you can get new flap valves (Rimmer Bros maybe? you could replace them, and then pein them in place with a very sharp centre punch.
As Harry says though, a new pump is by far the easiest way.
John :)
 
It's a long time since I've seen one of them things.
The valves are not designed to be repaired, just the diaphragm, really.
Can't you get a replacement from any of the "vintage" guys or, replace it with an electric pump, unless you want to keep it original?
What is it off?
 
I should have said, I have a rebuild kit which includes all the gaskets, rubbers, etc.! This kit does include two new valves which I know do fit this pump (some are 0.014" too small in diameter and there are plenty of them still out there.

I've seen a new pump at £90 and I'll admit it's probably easier, but I'd rather service and maintain the original. I'll try the Dremel with a fine head on it to grind it away gently.

Yes I love this kind of car maintenance as with a workshop manual, the right tools and patience, most of the jobs are doable at home. It's like with this pump, the further you space it away from the engine block, the weaker the pump pressure is -- it's easy to understand how it works.
 
Can't you get a replacement from any of the "vintage" guys or, replace it with an electric pump, unless you want to keep it original?
What is it off?

Over the years I have attained a few of these (I have four of them) all in different states, to keep as spares. I can't simply replace with one, but there are useful things like the body, glass bowl, etc. As I have a service kit I'd like to maintain it.

I'd rather keep it original (it's a Singer Gazelle) as possible to use weekly -- still uses points which are fine. I just keep it well looked after.
 
And for a long while, too I think. The old Willey's CJ2A jeeps used them in the 1940s. Latest installation from new I can find is on a late '60s Triumph Vitesse, with the final models replacing the glass bowl with metal.

I say "them" because I don't know what this model is called! I think they came in "types" but I can't find reference.
 
I think the were used into the early seventies. I seem to remember Hillman Hunters and Avengers having them.
Edit; I found this, maybe you've already seen this pabe, I don't think it is still for sale but, the numbers might be useful.
 
Last edited:
You can see the extra metal that holds those valves in place. Just turn them back to align with the housing using a pair of pliers. Those pumps are about £25 from places like Rimmers, Davind Manners etc. Make sure the seats are clean before replacing. Mended one on a Spitfire at the side of the road in about 30 minutes.
 
You can see the extra metal that holds those valves in place. Just turn them back to align with the housing using a pair of pliers. Those pumps are about £25 from places like Rimmers, Davind Manners etc. Make sure the seats are clean before replacing. Mended one on a Spitfire at the side of the road in about 30 minutes.

I saw the protruding metal, I will remove this with a Dremel or Stanley blade.

If Rimmer Bros. sell them for that kind of price, it might be worth getting from them -- I was seeing NOS ones for £90 which I don't want. I can't find it on their website so will e-mail them now.

Most things from this era are a joy to work on compared to modern I've found, so long as you don't mind regularly working on them!
 
I saw the protruding metal, I will remove this with a Dremel or Stanley blade.

If Rimmer Bros. sell them for that kind of price, it might be worth getting from them -- I was seeing NOS ones for £90 which I don't want. I can't find it on their website so will e-mail them now.

Most things from this era are a joy to work on compared to modern I've found, so long as you don't mind regularly working on them!
You dont need to remove the metal, just ease it back so the valve can pop out.

 
You dont need to remove the metal, just ease it back so the valve can pop out.


Thank you, I will inspect it on the bench at the weekend and look at doing this. I do want to give it a go to maintain originality and just for the achievement factor.

Rimmer Bros. have actually got back to me and said they don't stock any Rootes stuff, but the one in your link looks right -- thanks for sharing that. If it goes t'ts up with the valves, I'll go with the new pump and just carry a spare old one (along with the points, plugs, etc. that we all carry!)
 
Back
Top