: testing fuel pump?


fj40john
03-18-2003, 04:08 PM
Is there any way I can test a mechanical fuel pump off of the truck??

mano002
03-18-2003, 06:40 PM
hmm, off the truck, I don't know, maybe if you knew how many times the cam lobe hit the pump you could duplicate it on the bench and test pressure that way?????

Good luck.

fj40guy
03-18-2003, 08:24 PM
Off the truck.... press the lever in. Hold your finger over the SUCTION side. Let go of the lever. It should hold vacuum as long as you keep your finger over the port (I just check for 15 seconds or so).

Ditto with pressure on the output side (you have to keep pressing in the lever).

All the pump is: rubber diaphram. Two valves (inlet & outlet). Valves held down by a small sping. Quite often I've pulled the pump apart, and discovered a piece of crud lodged into the valve that caused it to stop pumping. Clean out the crud, reassemble... worked fine.

Oh, obviously I like the early fuel pumps that you can disassemble in the field... later with crimped cans... still check the same way, but have to be tossed. :(

Tom :usa:

smtyblt
03-18-2003, 08:31 PM
Yeh what he said will work I do that before I ever put a mechanical pump on anything

fj40john
03-18-2003, 09:03 PM
this is for an extra that I just found in a pile of parts in my garage. Guess it came from the PO. I will be getting rid of it, and wanted to be sure it was good before I advertised it as such. Thanks for the tips!!