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My carb was definitely having some troubles so i went ahead and bought the carb rebuild kit from midwest military. VERY complete kit, included everything i needed and quite a bit of other stuff. New needle and seat, new choke spring, every jet, even one of the brass screw-in plugs, in case one of the existing ones is stripped. All of the gaskets seem high quality. Compared to the Chevy rebuild kit i installed on my blazer earlier this year, this kit was almost like having an entire new carb.
I was surprised to see that the accelerator pump cup piston is made of leather, but it looks very well made and i would expect it to last at least as long as a rubber one. everything looks freshly made. The only very minor issue i noticed is that some of the small o-ring size gaskets that go around the jets seemed to have the center hole cut just a bit bigger than necessary, so they weren't a friction fit on the jets and were a little bit hard to hold everything together to get the jet started threading into the hole.

When i got my carb apart i found that the old accelerator pump cup was definitely not making a good seal, it looked like the leather had shrunk on one side and pulled back away from the round spring. I wonder if this is a sign of the carburetor getting too hot at some point? The carburetor to manifold gasket was also leaking badly, so i expect it will run a lot better as soon as i get the carb back on and installed

Hi Isaac,

Leather is an incredible material, but it contains natural oils which do dry out over time. Gasoline on leather causes the natural oils to dilute and then evaporate off with the gasoline. In effect gasoline dries out and shrinks leather, unless the leather is in continuous contact with the leather forever. Even if the leather never touches gasoline, it will still dry out naturally, become harder and shrink in size a bit. Sort of like women, but they never shrink in size.

As for dealing with O-rings a bit big......putting a bit of O-ring lubricant on your finger and then work the O-ring between your index finger and thumb to get it all over the O-ring. Not globs of the stuff, just a drop spread evenly to wet the O-ring. If you don't have O-ring lube you can use dielectric grease, Vasoline (petroleum jelly), or regular grease.

I've heard that Tom at Snake River also sells a nice carb rebuild kit too......not sure if it's from the same vendor John uses at Midwest, but I have heard there are also crappy rebuild kits out there too. Not sure how you tell the difference without opening up the kits and comparing parts. Anybody know?


regards,
bob

That would explain it bob, as this truck has sat for a minimum of two years most recently, and maybe longer before that. I bet sitting around lets the fuel evaporate and then the leather shrinks. Not too big of a deal, it was actually very easy to rebuild. I just need to look up the spec for the idle air screw. The only thing that I wasn't totally sure on was setting the float height, because it's a springy type needle valve. I ended up blowing through the fuel inlet and making sure it was "off" by the time the float got u to the float gauge I was using.

They aren't quite O-rings, just similarly sized. They're small and flat and made out of some kind of gasket material. I bet vaseline would still help to hold them in place though

oh, i did actually have one question, concerning how the tie-wire is meant to be used. seems only a few of the screws are actually drilled for tie wire, and i was wondering if the other screws are ones that have been replaced, or if only a few were drilled to begin with. I've never seen wire used on carb screws before, so for now i'll probably just leave it off, unless someone tells me the screws are actually prone to backing out. This is probably stuff that's all in the book...which is in the truck...which is not in my yard at the moment.

From the factory or after ordnance main support rebuild only the governors were tie wired and then had an ordinance lead seal with flaming bomb stamp attached to keep drivers from readjusting it to gain more top end speed thereby risking blown engines.

Carter wrote:From the factory or after ordinance main support rebuild only the governors were tie wired and then had an ordinance lead seal with flaming bomb stamp attached to keep drivers from readjusting it to gain more top end speed thereby risking blown engines.

Good information!

-T

pwrwagonfire wrote:

Carter wrote:From the factory or after ordinance main support rebuild only the governors were tie wired and then had an ordinance lead seal with flaming bomb stamp attached to keep drivers from readjusting it to gain more top end speed thereby risking blown engines.

Good information!

-T

Except for the spelling.

that's the kit I need to order