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I am planning to block off the mechanical fuel pump (mine failed and low pressure electric pumps are dime a dozen. mechanical pumps are hard to find here. Don’t even mind keeping even a few spares in the trunk) and go with an electric fuel pump.
This is what I intend to do and seek your expert advice on any things I have missed to address or if I am doing anything wrong. Might even help someone as a guide.
So here it is..
I am planning to use a 1/8 NPT tee (M/F/F) at the oil pressure sender at the front of the engine to mount the existing oil pressure sender and also to connect an oil pressure switch to wire the fuel pump via a fuse and a relay.
This would be the wiring diagram.
I am planning to use the fuel pump closer to the tank (in a secure location) and a return-type pressure regulator set at 6PSI (in the engine bay but away from heat sources).
I intend to use EFI type fuel filters, one before the pump (closer to the tank) and another one before the carburettor. Can low pressure electric pumps deliver fuel via these filters? Is it better to have a metal filter before the pump and a transparent filter before the carburettor? My Q-jet (among other things), had a missing fuel filter and the spring. So now that the carb is rebuilt, I am not inclined to go in that direction altogether.
Finally, block off the mechanical pump mounting hole with a plate.
Seems to me that it would be a LOT less trouble to just replace the mechanical pump with a new one. They really are very reliable if you buy a decent one. I honestly can say that I have never had a mechanical pump fail in the 50 years or so I have been driving and messing with cars. And if a mechanical pump does fail it usually gives you some warning like a leak instead of just crapping out and leaving you by the side of the road like the one in my Tahoe has done twice now in its 240K life.
I bought a new AC Delco one when I rebuilt the 307 engine in my Wife's Riviera last year. The original pump from 1984 was still fine but I was replacing everything else.
I have read in this forum of few cases where fuel pumps having failed in a very short time. Also, when including postage, I can buy 5 electric pumps instead of one mechanical pump. Plus mechanical pumps have to be imported only from USA and has to be model specific. Electric pumps available everywhere and can fit any sort of pump. But you got me thinking again...Bill
Even my air cooled bug has a mechanical pump and works without any trouble almost a decade now, despite being a very hot engine. But bug parts are common here unlike Olds (or any american car parts for that matter). Hmmm....
I didnt realize you were out of the states but it still sounds like way too much work and complication compared to replacing the mechanical pump. If you do decide to go with an electric one how about using one that does not require a bypass / return etc ? I think Carter has one. And the stock fuel filter in the carb inlet should be all you need.
I think you have all your bases covered. Installing the electric fuel pump will work great. You don't have to use 2 fuel filters but if it makes you feel safer go for it.