85 hp force stalls under load

[craigharris]

it is an 83 force 85 horse power.it runs fine in itlle but when you want to get up and go it just cutts out or runs real rough and wont make plan i tried a new fuel line and ball the plugs where wet when they came out. i checked all the plugs for spark and they had it but some one had said that it may still be the problem so i will put new ones in.and i am going to clean the carbs tomarrow after noon.hope that that works but i am looking for some more answers on why? thanks alot

 

[kslayte]

Re: 85 hp force stalls under load

I have a 1988 85 force and having the same trouble. I have research all this foroms and all I keep hearing is replace the fuel pump diafram, so I removed the pump unit and it was dryrotted and coming apart so I'm going to replace it but for now I just flipped it over and put it back on. If you do this you will see what I'm talking about. I also removed the jets from the front of the carbs and cleaned the and was still getting the same respons so I un screwed the the jets another 1/4 of a turn and it fired right up. If you are not sure about the feul pump locartion, it is were the fuel line goes into the engine and the line comes out of the engine and goes to the carbs. Ther is 6 bolts in it but only 4 of them hold the pump unit on. The 2 far left ones have nuts on the back of the unit so if you do remove all 6 becarful because the nuts will fall into the motor compartment,just remove the right 4 and the unit will pull away from the bmotor then you can remove the other 2 and then you will see the diafram we keep hearing about. If you find anyother helpull info please pas it on. Good luck.

 

[Frank Acampora]

Re: 85 hp force stalls under load

Before you go replacing things willy-nilly, the FIRST thing to do is to be sure that the idle speed is set at 700 rpm in forward gear in the water. Too low an idle will cause stalling and hesitation when trying to gear up and move the boat. Then check for too lean settings on the carb low speed adjusting needles. When you give it a hole shot under too lean conditions, the engine will sag and die. Before you mess with the carbs, replace the fuel pump diaphragm and gasket. Current gas with ethanol hardens them and you will not get proper fuel delivery to the carbs. On an 88 engine the fuel pump is located on the bypass cover. six screws hold it on. The bypass cover is the base and the pump and button valves come off as a unit. Regular flat head screwdrived is the only tool necessary.

 

[kslayte]

Re: 85 hp force stalls under load

With all due respect senor chief, only 4 SCREWS hold the unit on. The far 2 left Screws have nuts behind the unit that do not go into the block. I am a United States Marine AAV mechanic not a boat mechanic but what I wrote was good advice because mine is running great now. As far as the diagram is considered, it has 2 sides, the side that had been sitting in fuel for 2 years and has cracked and showing the copper screen that separates both sides. It dose need to be replace and I will do so soon, but as most Marines believe, Adapt and over come. As far as setting the idle speed to 700 RP M's and checking the lean and rich sitting, I would be just as great full to you if you would explain it to me as I was for giving me a ride across the Atlantic. Simper Fi. Sir. And God bless our Marines and Sailors.