76 johnson 85 horse

[badog229]

I have a problem that comes and goes really got me puzzled you can be wide open and run 5 miles or so and it will just go back to almost idle and you can back off and then open it back up and it will pick up again sometimes you have to shut it off and wait a couple min and its fine for a while.WE have changed two coils checked floats and carbs every thing seams fine.It seem to start when my father in law and a friend took it out one day and pluged the fuel line upside down and broke the nipple off thats on the engine,He then replaced it with one off a fuel tank. My ? is whats the chance that its sucking air when it builds up pressure and then gets gas when you back it off.The thing thats got us baffled is its eratic and dont do it all the time. Any and all help would be very app Thankyou and good boating

 

[tx1961whaler]

Re: 76 johnson 85 horse

My ? is whats the chance that its sucking air when it builds up pressure and then gets gas when you back it off.The thing thats got us baffled is its eratic and dont do it all the time. Any and all help would be very app Thankyou and good boating

Sounds reasonable that you have an air leak. The way to check is to take the fitting off of the fuel line, and connect the fuel line directly to the fuel pump.

PN for a new connector:
Part Number: 0376154
Description: FUEL CONN. BODY AY
Pack Qty: 1
Dimensions: 3.50 x 2.00 x 1.75 (in)
Weight: 0.10 lbs
Equivalent Parts: 0393334

shop.evinrude.com

 

[emdsapmgr]

Re: 76 johnson 85 horse

Possible you have a weak fuel pump. Next time it starts to slow down, prime the fuel hose bulb repeatedly. If the engine picks up and runs fine, the pump may be weak. A weak pump will not replenish fuel into the carb as fast as the engine consumes it. It will slow down, then pick back up when the pump refills the bowl. As the pump gets weaker, it will become happen more frequently. I actually removed the lower cowling hose fitting and plumbed the hose end directly to the plastic barb on the fuel pump under the cowl. Yes, it is permanent, but it eliminates problems at that hose connection.

 

[tashasdaddy]

Re: 76 johnson 85 horse

i eliminated the engine end connection on several of my motors, just took the tank line all the way to the fuel pump. if i need to remove tank i just disconnect at the tank. one less point to give you trouble.

 

[badog229]

Re: 76 johnson 85 horse

Thanks for the ideas,I dont think its the fuel pump cause the bulb is full of fuel when it happens ive tryed to pump it and its tight but i might try that anyway tired of working on it and ready to fish. Thanks again

 

[ezeke]

Re: 76 johnson 85 horse

Sounds like you need to rebuild the carburetors, paying particular attention to the float valves.

When you install the new carburetor parts, be sure to install the clip between the float arm and the float valve needle.

 

[badog229]

Re: 76 johnson 85 horse

Thanks I app all the info