I tested out that fuel pump. It's 12V DC and pulls .75 amps. That'
s about 9 watts.
Seems to work pretty well. It pulses or vibrates. I tested it out with a small bucket of water. The output is not continuous in the way I'm used to seeing with rotary pumps.
Does that make this a diaphragm pump?
It's a new pump off a diesel generator that was upgraded to have an "extreme cold weather" pump installed on it.
Looks like all I should need for the fuel system is this pump, a plain tank with a vented cap, a fuel filter and hoses to connect it all together.
Surplus center has cheap tanks off generators. Something like this already has the vented cap and a port on the bottom for a gravity feed output.
Surplus Center - 4.5 GALLON RED FUEL TANK
I tested this pump just running air, and it seemed to do a good job sucking. I think I could use another one as a vacuum pump.
I still need to figure out what I want for vacuum. It looks like the diesel engine has a mechanical vacuum pump on it. I believe the original Mercedes 240D car used vacuum for both the brakes AND for the power locks. However, that doesn't help me brake the truck when running it as just electric.
It might be best to have a vacuum pump and have it run the brakes in EV/Diesel/ AND hybrid modes. On the other hand, I was also told that I could convert to MANUAL brakes just by swapping out the master cylinder. I have no idea what it would really take to do that, but I'd like to investigate it.
If anyone has ever swapped a vehicle over to manual brakes, let me know how it worked out for you and any tips and tricks for doing it.