Merc 2.5 260 fuel pressure question ??

[liberatorx2]

Should fuel pressure drop when engine is reved up ??? Merc 2.5 260 with 39lb regulater. Installed new fuel pump , Cranked with engine in water tank. Idles at 37lbs on gauge but when I rev it up pressure drops 7-8 lbs. Is this correct or should it hold at 37lbs ?

Thanks Rick Moore

[StratosVT]

No it shouldn't drop that much. Sometimes under hard accelleration a 1 or 2 lb drop might be acceptable but 7lbs is not good.

[JCSmile]

I would be looking at checking the fuel pump. Doesn't sound good.

[Deznuts3570]

Sounds like the fuel pump isnt keeping up or you have a restriction somewhere thats not allowing the fuel pump to put out