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Anyone know where to get the internal packing parts for a M38 fuel primer pump or how to make the parts. Also, I'm looking for the injector nozzels. My pump is intact but the internal seals are split and dried out - I'd rather not buy a whole new unit if the original can be put back into service. Thanks for your ideas and information!

Try ebay. Just search for "M38 fuel pump"; there are often fuel pump repair kits listed. Got one myself a while back.

Try George Baxter at Army Jeep Parts he may have them
Rob

Check out "Then and Now".
http://www.maritimedragracing.com/then_ ... motive.htm

Thanks for the suggestions. Just to clarify, I'm looking for parts for the hand cold weather primer pump that mounts on the dash. So far, nobody I've called has replacement packings, just whole NOS pump kits with the pump and all parts.

Surplus City lists out the parts for the primer pump. No idea if they stock any of them. Looking at the diagram, I'd think you could buy packing material of the appropriate size and type and cut your own rings.

The military had leakage problems with these pumps and discontinued them on all models unless they were going to cold zones and needed them. If you plan on going to these areas, by all means fix it. If not, plug it off and put it on for looks. That is what I'm going to do with mine. It will dry out and do the same if you don't use it all the time. My 2 cents worth, John

Maybe McMaster-Carr carries what you need.

Since the M38. M38A1 and M170 all have vacuum operated accelerator pumps the hand (dash mounted) primer system comes in handy for all weather conditions. I've used them for over 30 years and they work great. They dry out when you park the jeep for long periods. All you need to do is unscrew the barrel end and pull the piston out and oil the cup and three gland packings with a light sewing machine weight oil.

If you let them dry out and shrink there are two problems. They will develop a very small leak but more importantly they will become a source of excess air in the intake causing the jeep to run lean.

The maintenance on them is very simple. Open it up. Clean it good making sure the two poppet balls are free to move. Lube the packing rings or replace them.

Thanks for the tips and information. The seals in my injector pump have dried up to the point where they are cracked, shrunken, almost dust and no longer usable. The ball valves are all in good shape. I'll continue to search for replacement parts or substitutes. I've been a pilot for 34 years and most, if not all, normally aspirated light aircraft use primer pumps to aid in starting. When I was starting the M38 for the first time, pouring a little gas into the carb, I wished the primer pump was functional, would have been a little easier!
Wes - question, do you have a good pic of the injector nozzels? I'm lacking those parts and am wondering if they can be made up.

Pete DeBella had the 6 cylinder Studabaker install kits with nozzles and fittings and pump fairly reasonable some time ago.


Engine Primer Kit 7358729

Beautiful pics! Thank you.

Late to the party but I have seen several good YT videos where the person made new glands, cups and seals using leather.
I'll track one down and post the link. [/b]


Here is a link.

https://youtu.be/WepZBN6k6tA

A guy on eBay sells the leather packing cups.