1988 85 hp Force Stalling when accelerates

[jbmarley30]

My boat ran fine the day I test drove it a week ago. I took it on the water the other day and it stalls when I try to accelerate past 1/4 throttle. I can only troll around 7mph.

I brought it to a mechanic and he ordered parts to replace after finding that the 3rd cylinder wasn't sparking. Fuel line, fuel pump diphram, carb kits, carb cleaner, and a power pack for the 3rd cylinder. I replaced all the parts and still nothing. I messed with the idle and carb adjustments while running and can't seem to get the power like beforethe 3rd cyl still doesn't spark but I thought I should have more power than this regardless. I also believe the 3rd cyl wasn't sparking when I test drove it and went around 40mph. There are pieces in this motor from three different year parts. Any suggestions? Thanks

 

[pnwboat]

Re: 1988 85 hp Force Stalling when accelerates

Stator, trigger, or coil could be causing the problem. Also the CD module for the other two cylinders can also prevent the one for the third cylinder from firing. CDI electronics http://www.cdielectronics.com/ WEB site has some basic ignition trouble-shooting tips. Can get kind of expensive to replace parts without verifying first. CDI site has been helpful.

 

[jbmarley30]

Re: 1988 85 hp Force Stalling when accelerates

Thanks, I'll try that site.

I also forgot to mention that it bogs out to a stall after 1/4 throttle.

 

[pnwboat]

Re: 1988 85 hp Force Stalling when accelerates

When you go to the site, go to the "Download" section and down load the Force DVA charts. Shows the resistance and output voltages for stators, triggers etc. There is also a step by step Force ignition trouble-shooting section.

One quick thing to check is broken connections. If you look at the wires on the terminal block for the CD modules, you'll notice that each lug on the wires has a small piece of black insulation (heatshrink) right where is is attached to the wire. I've found on more than one occasion, the wire inside the black insulation has actually broken. You can't tell. Even if you pull, the black insulation still has enough force to hold the two pieces together. If you notice any connection that seems to be more flexible at that joint than the others, it may indicate a broken wire.

 

[sbake]

Re: 1988 85 hp Force Stalling when accelerates

I have an 89 that did the same thing. I found the stator ring was binding/sticking when trying to rotate with operation of the throttle linkage. I had to pull the flywheel (which broke 2 pullers, it was rusted so tightly that eventually the key sheared) to get access to the stator assy. Then I had to shim it up .003 at all 4 mount points to keep it from binding when properly mounted. Don't know if you have the same problem, if so, this should help!

 

[maxum247]

Re: 1988 85 hp Force Stalling when accelerates

If your engine is bogging, look for air leaks in the fuel line and at the fuel pump.
Check to be sure the gas pickup in your tank isn't blocked by debree.
Check to be sure that the choke plate and throttle plates on the carbs are operating properly and not sticking.
These are a few things associated with power loss.

 

[jbmarley30]

Re: 1988 85 hp Force Stalling when accelerates

Thanks for the info!

I know the 3rd cylinder is one issue but I wanted to respond to the post about the carb choke plate sticking.

When I go to start it with choke, it only pulls the plates down for a split second. When I go to use the choke to start it for the first time, it seems to be turning a lot slower than without the choke. I have to get a friend manually hold it down until it fires up. I wonder if this could have something to do with the plates sticking like you said? Also, how can I check the throttle valves and fuel pump? I did already replace the diaphram. I hope I didn't cause a leak in the pump. The fuel line has been replaced also. I will check for leaks though.

Thanks

 

[maxum247]

Re: 1988 85 hp Force Stalling when accelerates

The choke plates will only stay closed as long as you hold the choke in at the key. Check to be sure your not forgetting to hold the choke on, done that myself!
Check the choke linkage for binding or lack of lubrication.

Take the fuel hose leading from the fuel pump to the carbs and put it in a bottle and have someone crank the engine, you should get a good stream of fuel as the engine turns over.

Make sure your battery is charged good, takes quite a bit to crank these engines over good.

Forty miles an hour is a pretty good speed, what type boat is it on, just curious!

 

[jbmarley30]

Re: 1988 85 hp Force Stalling when accelerates

Another thing I forgot to metion:
When I took the boat out for the second time this season I had to adjust the idle to avoid stalling when I put it into gear. I tightened it all the way. Again this was a sudden problem that I didn't have when test driving.
Tried lowering it and it wants to stall when trolling.

 

[maxum247]

Re: 1988 85 hp Force Stalling when accelerates

May be time to decarb the engine.

 

[jbmarley30]

Re: 1988 85 hp Force Stalling when accelerates

Got my motor looked at by a professional. They said it needed a flywheel kit. I'm assuming this is with the stator? Anyway, they then told me they do not know of anywhere to purchase the part. I found hard to believe since they are also a boat dealer but... Does anyone know where I could order one? Is it the stator I'm actually looking for?

 

[roadrunnr]

Re: 1988 85 hp Force Stalling when accelerates

Before you start troubleshooting by throwing parts at it, take PNWboat's advice and troubleshoot the cdi ignition system to verify that you actually have a bad ignition part. If you don't already have one, get a manual - Clymer or OEM. Throwing parts at a problem can get expensive quick with no resolution. I wouldn't replace the stator without first verifying that it is indeed bad!