MD3B Fuel Pump Question

[stxray]

I'm looking to change my mechanical fuel pump to an electric one. If you've done this could you post which pump you used.

What are the parameters (pressure, flow rate, etc.) I should be looking for? I did find
this one https://www.pegasusautoracing.com/prod ... ecID=9705 on line but not sure if it will work.
Any help or advice would be appreciated.

[WillieC]

Something like this should be fine:

Diesel fuel pump.png

I recently saw this set up on a smaller engine, but these things provide plenty volume for our usage.

I have one of these installed as a back-up, I also use it for bleeding the system. I also last year bought a brand new mechanical replacement from ASAP Supply in the UK. Reasonable pricing and quick delivery. I like the stock set up, but have heard horror stories from failed diaphragms dumping fuel into the crankcase. Seems like you would know something is amiss should that happen.

I have not used this electric pump for daily running, so I am mostly offgassing here. It is cheap enough to attempt. You will need to fashion a plate to cover the hole in the block where you removed the mechanical pump. Fairly straightforward with a drill press, hacksaw, file and green paint. And chunk of flatstock.

[stxray]

I got home today and looked at the Workshop manual. It indicates the lift pump feed pressure to be 9.2 - 12.1 PSI @ 2500 RPM. I found a 12v pump with 14 PSI and 35 gal/hr.

Is 2 PSI over the spec going to work or damage anything???

Thanks in advance

[stmbtwle]

A note about electric fuel pumps. Unlike mechanical pumps they do NOT normally shut off if the engine stalls, and could present a fire hazard. Make sure it's properly connected so that it does shut off.

[WillieC]

Ray, I can’t answer your question but the spec is the spec. That’s why I chose to replace the mechanical pump
The other comment about shutting it down is very good information too. Nothing another relay couldn’t fix. Etc.

[kerrye]

While having an electric back up pump strikes me as a good idea, changing an engine from being independent of electricity to being dependent upon electricity is a serious step backwards

[dkirsop]

When I bought my A25 the previous owner had installed an electric fuel pump as a backup to the mechanical pump. A few months later while doing regular maintenance I found the electric pump to be dead. Not to worry, there was a spare electric fuel pump in the locker - it was dead too! I threw them both out and bought a spare mechanical pump. At no time did I ever lose power on the water as the original mechanical pump gave stellar service and has proven to be the more reliable option.