Info needed: Fuel pump rebuild.....what time is it? modern fuels

[rob love]

I have successfully broken the rivet and moved the shafts across the diaphragms in the past, but your mileage may vary. I once salvaged about a dozen pump overhaul kits for the M38A1 jeeps which were heading for the garbage can, and they have repaired a lot of fuel pumps. Your success in this may vary, but since the part is already bought you won't really be out anything.

[Phil Waterman]

Hi

With the constantly changing fuels here in the States I've given up on manual fuel pumps. To maintain the fuel filter and line connections I've gone over to putting in a metal plate instead of the diaphragm, using galvanized steel. Left the check valves etc in place on the old style pump also left the glass bowl for visual check on fuel flow. The electric fuel pump jus push the fuel through.

Cheers Phil

[motto]

I have in past replaced the diaphragm re-using the original stem by drilling off the riveted end and then drilling and tapping the stem to take a screw or bolt. This has been quite successful.
I have no issues with the WW2 era mechanical, North American fuel pumps, most of which seem to be fitted with hand primers, so long as a suitable fuel compatible diaphragm is used.
I have in fact removed electric pumps installed by previous owners due to a potentially disastrous scenario involving a restored Dodge WC I once owned. The starter cable shorted on the fuel line and was perfectly capable of blowing a hole in it in which case the Auto Pulse would have pumped its little heart out until the ignition was turned off. Add to this that the vehicle was parked almost against my house and the loss could have been very great.
Modern vehicles with electric pumps have them powered in such a way as to cut power to them if the engine stops. They are not simply powered from the ignition.
This is to prevent an accident becoming a disaster.

David

[rob love]

Originally Posted by motto

, so long as a suitable fuel compatible diaphragm is used.
David

There is one more part that I have found to fail: The sealing surfaces of the little check valves. They too will suffer from the evil ethanol, allowing the pump to lose prime as well as reducing the effectiveness of the pump.

[maple_leaf_eh]

The first rebuilder I knew (or who admitted) to use in-line electric fuel pumps was Andre Gibeault. He had them on all his CMPs, and certainly on his halftracks. He's dead now, so I can't ask him how they worked, but he seemed convinced they were the solution to his view of the circumstances.