LOss of power

[schahl]

I have a 85 horse Johnson and when i take off it runs fine idles fine about half throttle if you try to go over that it will bog down and when you pull the throttle back half you can run just fine can anyone help on this thanks.

 

[cdn-pk]

Re: LOss of power

what year? i had a 77 140HP that had similar problem except at about 3/4 throttle, i search and found the fuel pump diaphragm was punctured and had a slow leak. the leak was out the back at the bleed hole. after i replaced the fuel pump i had to un-tweak the carbs i was messing with.

cheers

 

[larryg]

Re: LOss of power

possibility also that the carb needs cleaned

 

[Daviet]

Re: LOss of power

Check for any fuel leaks, check fuel pump output, most likely it's time to overhaul carbs. Make sure you remove the high speed jets and clean the orifices.

 

[schahl]

Re: LOss of power

This one is a 1975 model

 

[RR24]

Re: LOss of power

what year? i had a 77 140HP that had similar problem except at about 3/4 throttle, i search and found the fuel pump diaphragm was punctured and had a slow leak. the leak was out the back at the bleed hole. after i replaced the fuel pump i had to un-tweak the carbs i was messing with.

cheers

If this is the case, would you be able to pump the fuel bulb and make the motor speed up to test this?

 

[cdn-pk]

Re: LOss of power

In my case, pumping the bulb did help, but i didn't do it long as i was concerned with the fuel leaking.

cheers

 

[archcycle]

Re: LOss of power

Have you done a spark check yet?

This weekend I couldn't get over 3k and was idling smoothly (so it seemed). Pumped the bulb while pegged at 3k and it came up. Cleaned the carbs and checked the fuel lines and got nothing. Bulb turned out to be a total coincidence where right about that moment it started firing right. Spark check and visual (it was blatant!) showed a burned coil and no spark to one cylinder.

Easy enough to pop the wires off and test this first. I wish I had. Would have saved Saturday on the water..