TOPIC: 150hp fuel pump

hi, i found some time to work on my 1977 150hp, when i removed the fuel pump one of the hoses had a spring inside it, would that be there for reinforcement?

here is a photo of the fuel pump

The spring keeps it from collapsing and prevents sharp bends ( closing off )in the hose.

---

Have seen the plastic discs in the check valves sticky in these pumps ( too big in their cages ) requires new check valves or a bit of shaving on the OD of the disc.

thanks for the info professor, i will take a look at the check valves. i pulled the wiring harness today the wires are pretty deteriorated.

If those springs got cut or damaged be sure and replace them with springs that will fit inside the pulse hoses to allow the crankcase pulses to reach the fuel pump.
If you leave these springs out - as the professor warned - the pulse hoses will expand and contract with the crankcase pressure and the fuel pump won't receive strong enough pulses to keep adequate fuel supply to the carburetors at WOT and the performance will suffer.
Thom

i found a spring in only one of the two hoses connecting to the bottom of the fuel pump from the crankcase, so your saying that both of these hoses should have a spring? also the carbs have the small hoses that run from the fuel bowl to the intake, i think i read on a post that these hoses cause the engine to run lean. should i plug them?
thanks

I believe both hoses need springs in them.
I put a spring in both.

You don't need to block off or plug that mid-range jet Mercury foo-paw, just either pull the hose off the float top end and leave it like that, or simply remove the jet from the side of the float chamber top and leave the small hose connected to both ends.
You 'can' plug off the small hose - but you don't need to in either case.
Thom

thanks doc

Would this also apply to an 1986 115 Mariner?