Fuel pump options, Staying in its original location Options

[emerygt350]

I am having a very specific issue here. Pump no longer holds pressure after shutdown. Original location, original three port pump. It still pumps great when running, but no longer holds pressure. Need to fix that and quick. Do I have to replace it or can it be repaired?

[Olympic 914]

Why do you need to have the pressure hold when the engine is shut off?

Maybe its something I don't understand.

when I replaced my fuel pump, (Bosch 044) it came with a check valve that I removed.

I did not see a need to have pressure on the injectors when the engine is not running.

It always drops to zero when I shut it off. never have a problem starting up.

have since replaced that pump with a quieter pump (Bosch 69133) that does not have a check valve.

still starts right up on first turn of the key.

(IMG:style_emoticons/default/confused24.gif)

[wonkipop]

Why do you need to have the pressure hold when the engine is shut off?

Maybe its something I don't understand.

when I replaced my fuel pump, (Bosch 044) it came with a check valve that I removed.

I did not see a need to have pressure on the injectors when the engine is not running.

It always drops to zero when I shut it off. never have a problem starting up.

have since replaced that pump with a quieter pump (Bosch 69133) that does not have a check valve.

still starts right up on first turn of the key.

(IMG:style_emoticons/default/confused24.gif)

possibly that more modern pump builds pressure almost instantenously.

anyway. if you are not having problems then nothing to worry about.
whats that old saying - don't fix something that ain't broke.

with the originals the idea was to try and hold pressure in the injector ring to give you a fast start. mind you if you left the car for a week or so, all the pressure would be gone.
in original condition when new the system could hold sufficient pressure for up to 24 hours to give you a fast start. that would have helped with cold starts in north american winters. as the system ages it would lose pressure over shorter time periods.

i've got mine working tip top again in the 74 L jet with the fuel pump under the engine.
it holds pressure for an entire working day pretty much. or it did 3 years ago.
probably still pretty good now. if i do a same day start in the car at present it barely even turns the starter motor before the engine fires. leave it for a week and its about 2 or 3 cranks.