VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Fuel pump diaphragm

I sent the carb on the 38 out to be rebuilt. I got it back last week, installed it and fired the car up. After running for a bit I started smelling a strong gas smell and discovered the pump was squirting gas out the weep hole. A lot of gas in a short amount of time! I assume I now have a crankcase full of gas so an oil change will happen. The issue is rebuild kits are stupid expensive, over $80 with shipping. All I need is a diaphragm. I have an NOS pump to put on the car but I have no idea if it's ethanol resistant so I should replace the diaphragm on it as well before installing. I've heard that there are existing diaphragms that can be used that are technically for other applications but can be easily made to work by cutting new screw holes. Before I go spending $200 for two $5 diaphragms I thought I'd ask here if anyone knows a source for diaphragms alone or a less expensive pump I can buy and steal the diaphragm(s) out of?

I was going to suggest Then and Now Automotive but I could not find just diaphragms on their site.

You might call and ask https://www.then-now-auto.com/fuel-pumps/

Dave

I have the same problem, Have a new 50 year old AC pump and want to replace the diaphragam and only find expensve kits.

Is this perhaps the same ? If not maybe they could suggest a supplier , https://www.snydersantiqueauto.com/searchm.htm?type=merged&sterm=ModelA&searcht=diaphragm

The Snyder diaphragm might work. I have purchased them from C & P Automotive that advertises in the G & D. Also most kits are made by Feltz Terrill, Jr in De Leon, TX. The web address for their museum facebook site is: https://www.facebook.com/profile.php?id=100032389162385

Try The Filling Station, I bought just an ethanol resistant one from them a while ago.

other option is IF you have the existing diaphragm you can take it to a local gasket shop and have them cut you one out of ethanol (i.e. EPDM, Neoprene, Butyl, or all out Viton) not very expensive, local gasket shop here made me some for my fuel tank when i redid it.

Thanks everyone. I've contacted C&P and Terrill. I'll post my findings here. I also found a more modern application pump on ebay that, by appearances, the diaphragm out of might work. I'll have to cut my own holes. It was only $20 shipping included. I bought one with the idea of scavenging the diaphragm out of it. I'll also update that here.

Awesome... let us know what you find out

just an FYI the local shop here charged me around $10 to waterjet the gasket and it was Viton :) less than a 48 hour turn around

Unfortunately that's a resource not available here.

C&P Automotive no longer can help. Terrill Machine sells the whole kit or just the diaphragms. These are the diaphragm assembly with the stem attached. The diaphragms are $25 each plus shipping. Their phone number is 254-893-2610. I have two on the way.

Generally the Filling Station has a lot of that ethanol resistant diaphragm type material. If not have you tried Olsons Gaskets in Port Orchard Washington? They carry a lot of different gaskets for many models, not just Chevrolets.

ok, if you can not find anything, let me know i can talk with them and see about getting something cut and then ship it to you :)

Thanks but I think I've got it handled. Chip pointed me to the outfit that makes the rebuild kits and they also sell individual components. I have two of their diaphragms on the way. They are the assembly with the stem already attached.

As is normal for aftermarket items the holes in the diaphragm didn't align perfectly with the pump. The spacing on the pump is 2.75" center to center on holes straight across from each other. The spacing on the replacement diaphragm is closer to 2.9". The wife has a hole punch so I used it to oblong the holes. The new pump is back together and ready for install.

The story of my life with replacement parts - for almost any age vehicle!