Force Fuel Pump?

[MN_Jack76]

Hello fellow boating friends, I have a 89 Force 50 I overheated last summer on the river and when I noticed and throttled down it died. It hasn't started since, although it "wants to" with the starter spinning. I checked compression thinking I blew the head gasket and got about 115psi on both cylinders (although I don't know what the compression should be). Then I checked and have good spark on both cylinders. So I turned to fuel, I noticed without the connector on the fuel tank, it doesn't "shrink the pump bulb". I took the fuel line off the fuel pump and it seemed to pump fuel very weakly but possibly enough?? I then took the pump apart, but didn't see any tell tale signs of diaphram problems. I Know this is driven by engine vacuum or pressure and put my finger on the suspect (a bracket coming right out of the block), and it seemed to blow a "medium to low" positive pressure until a backfired burned my finger almost off - lol. Any Help by my fellow boaters would be greatly apprecitated!! - Jack

 

[roscoe]

Re: Force Fuel Pump?

compression is fine.

Get a SMALL squirt bottle and fill with fuel mixture.
You should be able to spray it in the carb, enough to start it and keep it running.
If it works, it is time to rebuild the fuel pump and the carb.

 

[MN_Jack76]

Re: Force Fuel Pump?

Thank you for the feedback! I know in school I was taught to spray wd-40 into the carburator instead of ether to try to determine if fuel was the problem to start an engine (due to the possible engine damage ether can cause I was told) The engine won't start by spraying wd-40. I also spun the engine before doing this and the plugs were "somewhat" wet, which made me think spark, but put a tester on both wires and also pulled the plugs and held them to a ground while starting the engine and had visibly bright blue and uniform spark. I'm allittle stumped, again, thanx for the feedback!

 

[JCF350]

Re: Force Fuel Pump?

Thank you for the feedback! I know in school I was taught to spray wd-40 into the carburator instead of ether to try to determine if fuel was the problem to start an engine (due to the possible engine damage ether can cause I was told)

WD-40 works for diesels. Oils the plugs in gas engines.

 

[roscoe]

Re: Force Fuel Pump?

wd40 used to use propane as a propellant, to get it out of the can.
They no longer use propane, so it is not likely to be combustible in the engine.

The fuel pump will only give 2-4 lbs of pressure, and very little volume.
But if you think it is suspect, rebuild it, under $12 for parts, and about 1/2 hour of your time.

 

[jerryjerry05]

Re: Force Fuel Pump?

I believe compression should be 145-150# spray some oil in both cyl then check comp..It might be your guage.If the comp goes up then the ring are prob siezed. Check comp then get back to me.Jerry

 

[MN_Jack76]

Re: Force Fuel Pump?

You know what JerryJerry, you were right on, I just did a compression test with a different guage and I got 90/120. Just pulled the head and don't see or feel any scoring (infact I still see the cross-hatch honing marks), the pistons look great and the suspect cylinder ring appears to be intact and free(as much as I can tell by gentley wiggiling the piston and looking top down) I'm hoping this is just as simple as a headgasket (I do see sign of possible failure). Any hints or techniques on how to prep the the head and block for installing a new head gasket would be greatley appreciated.

 

[MN_Jack76]

Re: Force Fuel Pump?

Roscoe, thank you for your reply - I realize now it wasn't the pump, I should have known considering I could hand pump the float bowl full and still didn't start. But now I know what to expect from the pump if I ever unfortuanatly go down that road!