No WOT

[Dublindog]

Still working on getting my 1987 85HP Force running right. Problem, no WOT. No tach as of yet, but I have one coming. Done so far, SeaFoam, Plugs, compression (130,130,128), good spark on all three, cleaned carbs (1 full turn out,idles and runs great), new fuel pump kit, new gas,all connections checked, bulb firm, vent clear, full battery charge. What I found today, the prop seems to be tight to the lower unit, it spins free but it seems to have rubbed at some point. I'll be shimming it out today. Does it make sense that the prop could be pulling in causing drag to the point the motor snubs out? The motor just dies at the point of getting on plane, if I give a bit of choke she stops dead. The motor runs smooth, starts right away, bulb stays firm and doesn't go flat. The best I can get is about half throttle and then it stalls. Any ideas??

 

[gatormeat]

Re: No WOT

maybe water in the fuel. do you have a water seperator/ filter connected? also I know you said the bulb stays firm but double check your fuel lines for any air leaks,also may be time for a fuel pump rebuild including the check valves. best of luck

 

[Dublindog]

Re: No WOT

It is new gas (drained and filled), the fuel pump has been rebuilt (not just gaskets), all lines are in great shape (one is new). I am about to give up, does a binding prop make sense. It does spin free, but sits very close to the housing, maybe getting tighter under load (forced into the housing)?

 

[maxum247]

Re: No WOT

maybe water in the fuel. do you have a water seperator/ filter connected? also I know you said the bulb stays firm but double check your fuel lines for any air leaks,also may be time for a fuel pump rebuild including the check valves. best of luck

You say it dies as the boat is getting on plane, from what you describe it doesn't actually stop running but stalls to an idle correct, and then if choked cuts off.
I beleive the engine isn't getting the chance to run long enough to colapse the fuel ball so that it's obvious there's an air leak in the system. Check the plug in connectors on the fuel line, I've had problems with those leaking air new on my 89 125hp Force and it caused basicly the same problem your having.

 

[john from md]

Re: No WOT

When the engine dies, is the ball still hard or does it have some give? If it has any give at all, I suggest that you change the three check valves in the fuel pump housing. Mine were sticking intermittantly and caused similar problems. I too rebuilt the entire fuel system with no luck. Those check valves are only $5 each.

If the ball is solid, then I would check that the floats are adjusted to the correct level. Asking for more fuel with low floats will give the same symtoms.

Another possiblity is that you are shorting out a wire under the flywheel as you move the trottle. Since the timing arm moves with the trottle, you may have a wire that has damaged insulation that is being moved into contact with ground or even opening a circuil. Another forum member had this problem some time back.

Hope this helps,

John

 

[Dublindog]

Re: No WOT

I'm not sure how hard is hard, the ball is always firm yet squeezable not soft or flat. Should the ball get hard to the point of not being able to squeeze it, if so should the ball be changed as well as the check valves again (there were 3 nickel sized valves replaced but the gaskets seemed very hard to put on them).

 

[john from md]

Re: No WOT

The ball should not be squeezeable as the lines should be filled to the carb float needle and you are trying to compress a liquid. If you can squeeze it any (normal squeezing not he man stuff), then there is a chance that either a float needle is bypassing or your check valves are bypassing.

If you replaced the check valves in the pump, only one required a gasket. That is the one that is removeable via two screws. The other two valves do not require gaskets as they are a press fit into the pump housing. You might check to make sure the valves were re-installed in the proper direction.

How far do you advance the throttle when it shuts off? Is it in the same place all the time? Have you tried to tie up to the dock and duplicate the problem?

Keep us updated,

John

 

[ronaldecole]

Re: No WOT

Hello -- I have the same problem, as soon as I try to accelerate -- at the same spot on the throttle the engine dies. I have been through just about everything and everything checks out okay. What bothers me is that I had a bind on the trigger/tower but I suspect I still have some kind of timing issue. The trigger is the only thing I can think of and now will have to start troubleshooting the ignition system.

Ron