7 replies to this topic

[H.M.M.]

Well thanks to 1984mini25 I've managed to get the engine turning over. Cheers bud.
The other issue that has arisen is the fuel pump isn't pumping. I have fuel.
I replaced the original pump that came with the engine as one of the pipe connectors was broken.
I took the old pump off my removed engine (fully working) and fitted to the new engine, they are both the sealed 800 pumps. Cranked over the engine and the carb reservoir is empty still.
Do I need to prime the fuel pump?
Or is the replacement pump not suitable? The both looked identical in the mechanism, just looked like different versions.
The pumps from a 1098, the engine is a 998A+.
If its not one thing its another.

[Doz1971]

I've never had to prime one?

Are you getting fuel on the output side?

[dklawson]

I do not work with the mechanical pumps but generally priming should not be necessary. The mechanical pump is mounted very low and the suction side of the pump should be gravity fed from the tank. I understand that there are perhaps a couple of different spacers that can be used between the block and pump mounting foot. If the right spacer is not present the pump can work poorly or not at all. I would make sure any spacers that were on your old pump were used when you mounted the new pump.

Before you freak out about the pump not working, disconnect the fuel line before the carb(s) and hold the open end of the hose in a catch jar. Have a friend turn the engine over on the starter and see if you do not collect fuel in the catch jar. If you do, the problem is likely to be a stuck or blocked float valve. This is not uncommon if your system had old hoses and perhaps you re-used one of them. The old hoses can shed rubber bits that move through the system creating blockages. If you re-used old hoses, it would be a good idea to replace all the old rubber.

[corrado vr6]

If the system was completely empty then it will take a while for the fuel to travel, when I did mine from empty lines it flattened a brand new battery and still no fuel! Eventually got there tho just took some cranking

[jaydee]

No you dont need to prime a mech fuel pump of a fuel filter.
If you have a fuel delivery problem, check fuel pipes for splitting or loose connections.

[Tommyboy12]

Mine takes about 45 seconds of cranking to cough back into life. Ive run out of fuel quite a few times...

[tiger99]

Usually they are quicker than that, but 45 seconds is still acceptable. If it fails to prime, it is likely sucking air through a leak somewhere, likely at the flexible sections near the tank or at the pump.

[H.M.M.]

Thanks for all the help.
I blew into the tank and that got the fuel moving, probably not the best may as you get a bit of blow back (not nice).
Pump works well and reservoir is now full. Just got to recharge the battery again as it flat.