View Full Version : Finally Rebuilding the 50 Commander Fuel Pump

01-19-2014, 03:02 PM
Around 3 years ago I bought a fuel pump rebuild kit from Dave Thibault for my 50 Commander. I had several NOS pumps so I figured I had some time till I needed to do this. I understand that the new fuels and the age of an NOS pump will both influence how long a pump will last on the car. I have had a couple AC pumps laying on the floor in the basement workshop for 4-5 years waiting for a rebuild. I kept the AC pumps to rebuild as they are generally a bit better quality then the brand x ones.

I have rebuilt V8 and regular 6 cyl pumps in the 1960's but have never tackled a pump that also provides vacuum assist. (I have to admit, I do not miss having to rebuild V8 pumps)

This is one of many projects I have delayed till I got to it and now retirement is giving me that time and these projects are also helping keep me occupied.

Anyway, I got the pump apart thanks to the shop manual. We are all so lucky that Studebaker had good shop manuals. This kit does not have any instructions with it. I have it torn apart except for removing the seal. A couple of the replacement parts are a little different but it is not hard to figure out the differences.

It was not bad to do this and is always interesting to see what makes these things work.

While the normal pump has a diaphragm in to create a suction to pull the gas, this one has two diaphragms and a couple check valves.

And yes, the CASO in me made my eyes open wide when I had to pay $65 for the kit but I am just thankful the kits are available.

It is amazing that this pump which has been laying in the basement for around 5 years and not smelling now lets off a faint gas smell after I opened it up.

I walked away till later as I do not have enough time today to dedicate to getting it back together. I probably will have my patient tried when I try to get the hooks into the end of the diaphragm rods.

01-20-2014, 01:35 PM
I usually make sure that both surfaces of the pump body are flat where they surround/meet the diaphragm. Place some fine sandpaper on a flat surface and, holding the sand paper still and moving the pump body, sand the pump body in a figure 8 pattern. You will be surprised how non-flat these things can be.

05-28-2014, 04:03 PM
Hey guys, I found this older thread and wanted to add on since I have the same pump. I have mine apart and got a rebuild kit with new rubber. My question is what is the procedure for getting the old rubber out and then resecuring the ends of the diaphragm rods? That is not addressed in the manual. My first guess is I can cut the little ends off with a dremel, but how do I get it back together? Is it a spot weld or some kind of solder? Thanks much...

05-28-2014, 05:12 PM
I did not have to cut any ends on the dremmel, the ends hook on. Yours should be the same. I did not have to solder or spot weld. It was probably the tricky part of the rebuild, getting the ends of the diaphram rods hooked back on. I thought this was documented in the shop manual, I am away from the manuals right now. I just scraped the old rubbers off with a knife being careful not to score the metal.

05-28-2014, 05:39 PM
Hey Milt, I guess I am not understanding how you got the old rubber diaphragm off each rod. They are sandwiched between metal discs. I will try to post a photo if that helps...

05-28-2014, 06:55 PM
The kit I used which I got from Dave Thibault had the diaphragm attached to the shafts/rods. I am sorry I did not understand your original question.
I have no clue how to best change the diaphragms. I would be concerned that whatever I did would not hold together.

05-28-2014, 07:28 PM
The kits I have seen have the diaphragms already sandwiched between new discs. Is yours different?

05-28-2014, 09:11 PM
Yes that photo is my old rods and rubber, with the new rubber below. Looks like I got a kit that's more diy than I thought. I didn't know there was anything easier out there. Thanks guys. I'll figure something out...

06-03-2014, 03:43 PM
Okay, so it looks like I need the fuel pump rods with the rubber already attached. Does anyone know a vendor that has individual pump parts so I don't end up buying a whole 2nd kit? I found the instructions to my kit, but I just don't feel confident doing all the steps outlined, to attach the new rubber to the old rods. Thanks much.

06-03-2014, 08:11 PM
This is the best place to find a rebuild kit.