Help-fuel pump wiring diagram 78 Sunbird 231'

[mossman]

Just finished putting newly rebuilt 231 in my Sunbird. Electric fuel pump was working before the rebuilt, and now it is not. Evidently there is no fuel pump relay on this system but the fuse is ok. Also replaced the oil pressure switch that has the fuel pump cut off in it so I doubt it is that. My old Chilton manual doesn't have the wiring for this car. Took pump out of tank and verified that it was indeed working. Fuel guage is working.Any help?

Peace,

Mossman

[gerbsinmd]

Sounds like you're not getting any oil pressure. You can jumper the fuel pump at the plug that goes on the oil pressure switch. You can put a wire between the outer terminals in the plug. Make sure you have oil pressure before you do that though or it could be really bad......

[mossman]

Hey gerbsinmd:

Did what you said. Ran jumpers between the two terminals and simply turned the key on without starting the engine. The pump worked. The question is, why don't I have oil pressure, and what do I do about it? Could it be that since the motor has not been run yet that oil hasn't completely coursed through the filter and galleries?

MM

[vega_man_larry]

You need to prime the oil system to get oil pressure before you start your engine for the first time, or after yo do an oil change. I disconnect the coil wire after and crank till I get pressure. Then I reconnect the coil wire. The electrical system that runs the fuel pump is designed to stop pumping fuel when there is no oil pressure. This protects the engine and protects you in case of an accident. No oil pressure equals no fuel as you have found out.

Larry

[PeerStalkHawk]

As Darrel and Larry mentioned, the Buick v6 oil pumps need to be primed before starting a new engine. If you didn't already, you have to pack the oil pump gears full of Vaseline or Petroleum Jelly well before installing the thrust plate or oil filter mounting cover. It helps to draw oil up into the pump initially. Check to be sure the distributor shaft gear pin is engaged down into the oil pump gear slot fully. Sometimes the distributor body and shaft might not be quite fully seated or the distributor gear isn't fully seated in and requires some extra wiggle and pushing at. Also check for any binding or clearance problems with the oil pump gears. Then again, the problem could be from a totally different reason too. Good luck and I hope you get it going easily! ........Dean.

[mossman]

Got engine running with oil pressure. Removed distributor and turned ignition on. Took electric drill and turned oil pump shaft until oil(engine) light went out. Jumped oil pressure switch to prime new carb from fuel pump. Replaced distributor and the rest is history.

MM