Fuel Pump Rebuild
Posted: Mon Jun 11, 2012 7:27 pm
This is an informational post for those who might journey into the interior of your M38A1 fuel pump AKA, AC 4535. This is a dual action pump with fuel and vacuum sides. On the vacuum side, there are two different diaphrams possible. One early and one late. You might have guessed by now that I bought the wrong one.
The rebuild kits are identified as either a T or W (for window type) so you will need to disassemble yours first to determine which you have. I purchased my kit based on model year not knowing at the time that my A1 engine had been swapped out by the military for an earlier engine. But any year pump could be on yours.
The good news for me is that the supplier is sending the correct W type gratis without my having to buy a complete rebuild kit to get the one part I need.
Also, I have the underwater fording type venting and the hand lever to manually pump the fuel to the carb. The download does not show this lever so pay attention during disassembly to orient the part correctly on your way back up. Otherwise, the download was very helpful as no instructions came with the kit.
Hope this helps you. I saw no mention of this change in kits anywhere but the suppliers apparently know about it. I understand the remaining W type is just a real pleasure to hook up, being a blind area to fish around in. I may have an update to this post telling you to never attempt this without first locking up your guns and hammers in a remote area.
Mike
The rebuild kits are identified as either a T or W (for window type) so you will need to disassemble yours first to determine which you have. I purchased my kit based on model year not knowing at the time that my A1 engine had been swapped out by the military for an earlier engine. But any year pump could be on yours.
The good news for me is that the supplier is sending the correct W type gratis without my having to buy a complete rebuild kit to get the one part I need.
Also, I have the underwater fording type venting and the hand lever to manually pump the fuel to the carb. The download does not show this lever so pay attention during disassembly to orient the part correctly on your way back up. Otherwise, the download was very helpful as no instructions came with the kit.
Hope this helps you. I saw no mention of this change in kits anywhere but the suppliers apparently know about it. I understand the remaining W type is just a real pleasure to hook up, being a blind area to fish around in. I may have an update to this post telling you to never attempt this without first locking up your guns and hammers in a remote area.
Mike
