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1986 85 hp Force Leaking Fuel Pump

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parker1320

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I just installed a new diaphragm and gasket on my 1986 Force 85 hp. When I pumped the fuel ball fuel squirted out of the fuel pump from all around. I tighten the screws but that did not help at all. I am wandering if I installed the diaphragm in wrong or was it defective. I got the kit from E-bay when I got the carburetor kit which was trash. None of the parts fit or matched. I may have the same problem with the diaphragm too. I feel the gasket was too thin. So I ended up with going to the local boat dealer getting the correct carburetor kit which fit perfectly. I am trying to get the boat ready for spring. I have read many forums that state no gasket sealant should be used in the carburetor but nothing on the fuel pump gaskets. Any help would be appreciated. I do have a service manual for my motor which does not indicate the position of the diaphragm.
 
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I just installed a new diaphragm and gasket on my 1986 Force 85 hp. When I pumped the fuel ball fuel squirted out of the fuel pump from all around. I tighten the screws but that did not help at all. I am wandering if I installed the diaphragm in wrong or was it defective. I got the kit from E-bay when I got the carburetor kit which was trash. None of the parts fit or matched. I may have the same problem with the diaphragm too. I feel the gasket was too thin. So I ended up with going to the local boat dealer getting the correct carburetor kit which fit perfectly. I am trying to get the boat ready for spring. I have read many forums that state no gasket sealant should be used in the carburetor ;but nothing on the fuel pump gaskets. Any help would be appreciated. I do have a service manual for my motor which does not indicate the position of the diaphragm.
 
The diaphragm should fit only one way.
It should be in the shape of the number 8
One end being bigger than the other, see pic.
There is no sealer used.
The diaphragm should be real thin.
Some pumps have a spring behind the diaphragm.See second pump.
It takes a bit of tuorqe to make the pump not leak.
21.gif
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Thank you Jerryjerry05 for the reply. I have the upper unit without the spring. When I stated that I may have installed the diaphragm the wrong way, I was wandering if there is a front or backside configuration. I have the unit installed as shown in display. I took it apart again today and the gasket has tears on it not the diaphragm. So I will be picking up another gasket from my local boat supply outlet. Also thanks for stating that the screws need to be torqued down to prevent leakage. I will post when I get the new gasket installed.
 
I installed the new diaphragm and gasket as advised. There was no leaking. Now I go to turn the motor over and I get backfiring when it tries to start. It has new plugs and the carbs were rebuilt with new parts. The compression was 130/132/130 before rebuild of carbs. Now I can't get it to start just backfiring out of the exhaust. What could this be.
 
I will re-tighten the carb nuts but I believe that it may be the flywheel key sheared. It acts like it wants to start but it just turns and spits.
 
I re-tightened the carb nuts today and it started. No backfire. However the middle carb leaked like it was raining. Out of the vent hole and the throat. Took it back off and blew out all holes. Checked for signs of any small particles nothing. Checked the float to make sure that it was level as shown in the factory manual. Put it back on still leaking bad. Took it back off and put the old needle back in to see if it that would slow up the fuel flow. No good. Now I am thinking that the carb has an internal problem that I cannot find. I am at the point of trying to buy another carb to see if that would fix it. Never saw gas pour like that on any engine unless the hose was split. These are brand new hoses and they are not leaking at all.
 
The only way the fuel cmes out the side is the flaot or needle or the seat is damaged?

The seat could have the seal missing??
Does the needle have a rubber tip? Yes, then the seats all metal and inspect for damage.
NO then inspect the seal in the seat.It's a rubber oring and carb cleaners and soaks can hurt it???
The rubber tip can get deformed, inspect, should be smooth.

Is the float metal? It should be(I think) make sure there's no fuel inside the float???

Float, if not set right it can case the flooding.
Carb upside down, float level.
Carb right side up, the float drop it should almost touch the center post.
Google Force carb setup by FrankA
 
I have the brass float. I have the metal tip needle. I will take it apart again and re-clean the carb. I will use both carb cleaner and my ultra sonic cleaner.
 
Well here is the update. I took the carb back of the boat. I looked the carb over. I put the float in water it floated I looked into the needle port and I saw the problem. I put my glasses on to see that the seat was sideways. Yes I did it when I installed the rebuild kit. So I removed the seat again. I still sprayed carb cleaner in all the ports and blew them out with air. I then put the unit in the ultra sonic cleaner for 30 minutes. I then reassembled the unit making sure the seat was correct. I checked the float height again to make sure it was correct. I then blew it out again with air. I re-installed the unit on the boat. I pumped the ball no leak. I then tried to start it nothing. I used the choke and it fired right up. I let it run for about 5 minutes before shutting down. I will over the weekend run some Sea-foam thru it. I want to thank Jerry for all your help and advice.
 
Glad it's working.
Seafoam In my opinion is a waste of $$$
It's supposed to remove carbon, NOT.
Did a test against the 3 I listed.
Put 2 pistons in separate jars, added SF and PT
The SF did NOTHING
The PT melted the carbon off just setting over night.

You should use Mercury's Powertune or OMC's Engine Tuner
Yamaha makes the same product I just don't know the name.
Follow the instructions on the can.

Or any auto parts store get a carb/injector cleaner.
In a black or grey bottle shaped like an upside down funnel.
Called Chevron with Techron.
I mix 1 or 2 in a gal. of "regular" gas, unhook the fuel line and somehow hook the mix into the system.
Run the mix for 20 min. Let set over night.
Then run again for 20 min. let set over night.
Then pour the rest in the gas tank.
 
Thank you very much. Your insight is awesome. Not many people would take the time to help others without a charge. Keep up the good work. Thanks for the tip on Sea-foam. Just was hoping for something to clean out the built up carbon that may be there.
 
I get on here in the mornings.
Doing this helps wake up my sleepy brain.
And I enjoy it.
But hey, if you wanna pay??? We can work out something :) :)
 
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