Mercury Fuel problem/Question

[cmpulse170]

Guys the last time out w/ the boat I had a hard time cranking the engine the prime bulb would never get firm and engine would spin over but never fire. I finally got it running and it was fine the rest of day until I was loading the boat. Then it started all over again. So I've checked for a anti syhon valve, which I don't have. Then checked the hose from the fuel tank back to the engine. I took the hose loose from a fitting inside the cowling put a bolt in the end of the hose and it prime right up. So I know the hose from the fitting back to the tank is fine. What I'm wondering is whether or not it could be the fitting and hose that goes to the fuel pump or do I have a bad fuel pump? Here are some pictures of the hose and fitting.

BTW, It's 1999 Mercury EFI 200 HP.

[kct11]

with the motor being 9 years old, i would rebuild the mecanical fuel pump. it is what keeps the canister for the electric pump full. the fact that you could get the bulb firm with the bolt in it could mean there is a tear in one of the pump diaphrams, or the float/needle and seat in the canister was not working for some reason........the gas is going some where if it will not firm up. also check all the ruber lines for leaks. good luck.

[2springers26]

all engines built prior to 2000 with a square mechanical fuel pump needs to have the updated pump rebuild kit installed. the check valves are plastic now instead of rubber wich ETHANOL fails. causing a flooding issue. (P balls not getting hard). if the pump is good you need to address your float/ needle & seat. depending if you have a EFI you have 1 of each. if you have a carbed engine you have 6 of each VARNISH plays a BIG part of this failure. Kurt

[cmpulse170]

all engines built prior to 2000 with a square mechanical fuel pump needs to have the updated pump rebuild kit installed. the check valves are plastic now instead of rubber wich ETHANOL fails. causing a flooding issue. (P balls not getting hard). if the pump is good you need to address your float/ needle & seat. depending if you have a EFI you have 1 of each. if you have a carbed engine you have 6 of each VARNISH plays a BIG part of this failure. Kurt

Kurt,
I've ordered a pump repair kit from the Merc Dealership today, it should be in tomorrow. Then I'll tear it apart to see what I got. I've got the EFI motor if that helps.

[cmpulse170]

I got my Diaphragm kit for my fuel pump today. I've got the fuel pump back together, prime the bulb, 3 squeezes and she fired right up. :thumb: