Force fuel pump

[Frenchy2]

85 horse power motor has ran great for the 4 years that I'ved owned it. The problem began with the motor cutting out after opening the throttle. The boat would almost come up to speed then the motor would cut out. Restart and it would run really rough and then even out. Seems like it is not getting enough fuel. I replaced the primer bulb and did away with the quick disconnect. Problem stayed the same I figured it was time to try and rebuild the fuel pump. I took fuel pump off the motor and dismantled it. Some of the parts in the fuel pump are missing. There is no gasket (h) no booster spring (f) and no booster spring retainer (e). The letters in parenthesis are from the diagram in the force service manual. How is it possible that this has ran for the last 4 years. It doesn't look like these parts come with a rebuild kit. Will they be hard to find ?

 

[eurolarva]

Re: Force fuel pump

You will need to post your model number and horse power of the motor. Force used two completely different types of fuel pumps.

 

[Frenchy2]

Re: Force fuel pump

You will need to post your model number and horse power of the motor. Force used two completely different types of fuel pumps.

85 horse power model # 858f9b. The rebuild kit # is for the pump is.

18-7806

 

[rudedude]

Re: Force fuel pump

My 1986 Force 125 did not have all the springs your talking about ether.

Just a diaf,and 3 little check valves. Thats how they built it.

 

[Frenchy2]

Re: Force fuel pump

The manual shows a spring and how to install it with a putty knife holding it in. While getting the holes lined up and putting 2 screws in you slide the putty knife out. Then assemble the rest of the way.

 

[eurolarva]

Re: Force fuel pump

here is a blow up of your fuel pump. Which part numbers are you missing?

 

[Frenchy2]

Re: Force fuel pump

The only part that I'm missing is 16 the gasket. Looks like all I need to do is order the rebuild kit and I'll be all set. I wish I could post the blow up in the force manual I have. It shows a spring and a retaining clip sandwiched in between 16 and 12 centered in the bigger half of the diaphram. I kinda freaked out when the parts inside my pump didn't match up with what I found inside.
Thank you so much Eurolarva you really saved me a lot of aggravation.

 

[eurolarva]

Re: Force fuel pump

There was an earlier post either this week or last with the same issue concerning a putty knife and fuel pump. There must have been some that is like the one your manual describes. Merc site jives with my chrysler book on the pump. A 18-7806 pump kit ought to fix yours up.

 

[rudedude]

Re: Force fuel pump

I would think manuals would cover all applications in multiple years and models . I seen the post on the putty knife use and spring thing, figgured it was a merc thing.

 

[Frenchy2]

Re: Force fuel pump

I ordered the pump kit. I hope this fixes my problem the diaphram doesn't look damaged or worn in the least bit. I don't understand why my manual has it all fubar.

 

[MikDee]

Re: Force fuel pump

Wait, I have an 89' Force 125hp and according to my serial # the fuel pump I have is shown to have the spring, & disc, parts #9, & 10, in this Mercury parts link? Why is it different then the one shown previously here by eurolava???

http://www.crowleymarine.com/mercury_parts/1288/80.cfm

 

[eurolarva]

Re: Force fuel pump

Mercury must have started changing them in 89. If you look at the pumps for the 125 in 1988 they are the same as the one for the 85 HP. That pump design has been pretty much the same since 1970. My 67 chrysler has a glass sediment bowl on it but it still takes the 7806 kit.

 

[gregmsr]

Re: Force fuel pump

The manual shows a spring and how to install it with a putty knife holding it in. While getting the holes lined up and putting 2 screws in you slide the putty knife out. Then assemble the rest of the way.

Thats right like mine, a two stage pump. And BOY did the new diaphram make a difference! Took it out yesterday for first time sense the re-build. My old diaphram looked just fine but with the new it really helped the rough low speed idle and when shoving to WOT it jumped right out of the water with out any hesitation.
So the moral of the story is "don't wait or hesitate to install new diaphram in your fuel pump". You'll be glad you did!

 

[MikDee]

Re: Force fuel pump

Mercury must have started changing them in 89. If you look at the pumps for the 125 in 1988 they are the same as the one for the 85 HP. That pump design has been pretty much the same since 1970. My 67 chrysler has a glass sediment bowl on it but it still takes the 7806 kit.

Wow, That's odd, I wonder why the added the spring? Anyway, it didn't seem to make much difference on my motor when I rebuilt it, but then again my diaphram looked in good shape to begin with, somwhere along the way it must have been rebuilt before.

 

[Frenchy2]

Re: Force fuel pump

Thats right like mine, a two stage pump. And BOY did the new diaphram make a difference! Took it out yesterday for first time sense the re-build. My old diaphram looked just fine but with the new it really helped the rough low speed idle and when shoving to WOT it jumped right out of the water with out any hesitation.
So the moral of the story is "don't wait or hesitate to install new diaphram in your fuel pump". You'll be glad you did!

Yeah baby thats what I'm talking about. I'm waiting patientently until the kit arrives.

 

[rudedude]

Re: Force fuel pump

After I changed mine out it just poped up and on plane, ran a lot smoother also.
Mine "looked" just fine also.

 

[Frenchy2]

Re: Force fuel pump

Thanks everyone parts arrived yesterday. Took the boat to work with me today. Went to the lake and launched the boat. The motor wouldn't start. I spent like 10 minutes cranking away. Nada never even a cough. When I pumped up the fuel bulb I could hear the carb bowls filling. I know it was getting fuel. Checked the spark seemed a ok. Was just about to give up. Actually let go of the key on my last try and it sputtered. Hit the key again and it started. Right of the bat I knew it sounded better than before. Took it out on the lake and opened her up . Popped roght up on plane and ran like a champ. Fished for bluegills until I caught 12 8 to 9 inchers and called it a day.

 

[eurolarva]

Re: Force fuel pump

Cool another blue gill fisherman. My kids favorite food. Glad to hear the pump kit did the trick. As cheap as they are it should be the first thing anybody does to their motor.