1986 85hp Force Outboard won't get high rpms.

I bought this boat not running. I took off the flywheel and the stator was fried. The previous owner had replaced the cd units and the coils to try to elimate those problems. So I bought a used stator off of ebay for cheap and put it on and its running now. But when I got it in the water, first of all it idles low and will sometimes shut itself off when in neutral or shifting into drive. The most important problem I am having is when I have wide open my boat will max out at 20mph and sometimes it takes 5 minutes for the boat to get to that speed when we hit it from neutral. Could the stator be weak? Is that even possible? Should I just go out and buy a brand new one? Any other suggestions would be appreciated. Trying to plan a boating trip soon. Thanks.

Re: 1986 85hp Force Outboard won't get high rpms.

You should do a compression and spark test.Then get back with the results. Do you have a tach?If so what kind of rpm's are you running?Jerry

Re: 1986 85hp Force Outboard won't get high rpms.

We did the compression test and all 3 cylinders have compressio from 140-150. Then we did the spark test and our top cylinder is not getting spark. I could have sworn that when we replaced the stator we were getting spark on all 3 cylinders. We took the cd units down and tested the wires for power from the stator. For some reason, we only have 2 cd units and i guess that 2 cylinders get power from 1 cd unit and the other give power to only 1 cylinder, but for some reason the orange wire coming out of both cd units does not get power. Any ideas?

Re: 1986 85hp Force Outboard won't get high rpms.

Each CDI unit can fire two cylinders. On the three cylinder engines, you have a spare. I just can remember which unit only fires one plug.

Is your ball hard when the engine is shutting off at idle? What rpm are you getting at WOT?

Regards,

John

Re: 1986 85hp Force Outboard won't get high rpms.

So we found out that the choke was stuck and we were giving the engine choke the whole time. So we fixed that thinking we were good to go, that seemed to explain a lot. We took it to the lake today and it started right up idled fine out to the no wake zone, I hit the throttle and it took off, we were screaming, it has never ran good until we got it. We maxed out around 40mph. Not long after that the engine revved down and the more and more so we pulled the throttle back to shut it off and then it started miss firing. We pulled the throttle all the way to neutral and then it shut off and we could not get it back on. Had to be towed in. It seems like the flywheel is not spinning fast enough to start the motor, so I dont know. Any ideas now?

Re: 1986 85hp Force Outboard won't get high rpms.

Did your battery die, maybe time for a new starter?

Re: 1986 85hp Force Outboard won't get high rpms.

The start is consistent force but something else is going on, we tried jumping it with battery box. The starter is working fine. It started fine right before we hit max mph and then died.

Re: 1986 85hp Force Outboard won't get high rpms.

If the engine slowed down from overheating/not enough oil, then the slowing was from friction. This eventually will lead to the engine siezing up. Yours may not have got to that stage but you still may have scoring in the cylinders and bearing damage and that is why your flywheel is not spinning fast enough.

Take the plugs out and turn the engine by hand. It should be easy to spin. If not, it is time to pull the head and look for damage.

Regards,

John

Re: 1986 85hp Force Outboard won't get high rpms.

So if that is the problem, What is our next step to fixing it?

Re: 1986 85hp Force Outboard won't get high rpms.

If the cylinders and pistons are scored, it means at the very least, replacing the pistons and honing the cylinders. It may also include replacement of the main bearings as these would have been starved of oil also.

If you suspect that the engine has such damage, you really need to tear it down and address it. I once ignored the symptoms and had a bearing come apart in the ocean off of Cape May. My kicker got me back but it took a long time and the engine cost me time and money to repair.

Regards,

John

Re: 1986 85hp Force Outboard won't get high rpms.

Could be a poor electrical connection on one of the coils. Either along the spark plug wire or at the other two wires coming from the coil. Had this happen to me just the other day. Motor ran as if I had blown a CD module. Noticed one of the spark plug wires had come loose of the coil. Reattached, motor ran fine.

Re: 1986 85hp Force Outboard won't get high rpms.

We took out the spark plugs and turned the flywheel without any issue. We also turned the engine over without the spark plugs and the flywheel spinned fast. It is getting fuel, there is no wiring shortage. It is getting spark on all three cylinders, and the battery is fine. Like I said we know we have something right because we had it running 40mph for about 2 minutes then lost rpms and now it wont start. My friends dad looked at and said its almost for sure a timing issue. So what parts will define the timing? We replaced the stator when we first got it and just had the flywheel off today and it looks fine. What do you guys suggest?

Re: 1986 85hp Force Outboard won't get high rpms.

Go thru your fuel system again and look for trash, starting at the tank and work your way to the engine. You've got the ingrediants for the engine to run such as spark on all cylinders, good compression, strong battery, that leaves two things fuel or timing, check everything that has to do with the fuel system, make sure there are no air leaks anywhere like the fuel line or mounting gaskets at the carbs.
Rebuild the fuel pump if it hasn't been.
Clean your carbs.
Check the timing.

Re: 1986 85hp Force Outboard won't get high rpms.

Timing can be checked using the starter at cranking speed. Look in your book and it will tell you how to do it.

I can only assume that you left something lose when replacing the stator as timing doesn't normally change all by itself. Check the timing linkage to see if something is lose.

Regards,

John

Re: 1986 85hp Force Outboard won't get high rpms.

The stator was put in a year ago, thats fine unless its weak if thats even possible. What would cause the engine to run at top speed for 2 minutes then not start a minute later. What could happen to the fuel system during that time?

Re: 1986 85hp Force Outboard won't get high rpms.

Any last thoughts from anyone before we give up on this? We checked fuel line and it seems to be pumping fine. We can fix anything just have no idea what to fix.

Re: 1986 85hp Force Outboard won't get high rpms.

If the engine starts fine and dies after running for a while when you idle, and won't start well after that, it is probably a mixture issue.

This can be caused by incorrect mixture screw settings and poor fuel pressure. You should set the mix screw 1-1/4 turn out for all carbs and go out on the water. Run it idle and start unscrewing until you feel some results. For me, it was actually 2-3~ turns until I got anything because the screws had been improperly seated. Just play with the screw, remembering that starving your engine of fuel can be problematic.

Float setting and needle seating are also causes. Adjust your carb's floats according to a manual. A crude check to do for the needle seat is to take the bowl off the carb and hold the float up with your finger. Squeeze the bulb and see if gas squirts out of the carb or not. Let it down and then squeeze. You should see some squirting out. If it doesn't stop the flow with it in the up position, it needs cleaning or repair. Also inspect the float for gas-logging, pinholes, etc.

Fuel pump rebuild is cheap and routine, so you might want to just do that anyway to check it off the list, if it hasn't been done already. The crankcase pressure nature of the diaphragm pump makes it susceptible to backfire damage. You can get a T and gauge to check fuel psi, but you're almost better off, cash wise, replacing the diaphragm.

Timing can cause a problem, and I'm not saying don't check it, but if it runs at all its probably not the root cause.

Re: 1986 85hp Force Outboard won't get high rpms.

If comp is good and spark is good.If the fuel pump is working right and you say it dies under load then the problem is likley to be in the fuel system.
Did you check the ball?A brand new ball can be bad an old one can have a bad check valve. How about the antisiphon valve?Is anything clogging it?Any extra connections in the line(quick connect).They are famous for going bad.Take the pump apart and make sure it's put together right.No holes in the diaphram.
Set the idle air screws.In until it bottoms then out 1 turn. Make sure the linkage is all working correctly.Is the timing advance moving when you accelerate?
You removed the flywheel make sure the key is in correct.Off just a little and it won't work. Jerry

Re: 1986 85hp Force Outboard won't get high rpms.

The engine right now will not start. It turns over but it seems weak and not turning over fast enough. It wont start even when we spray staring fluid in there. It sounds like its chugging and firing incorrectly. We took off the fuel filter and all the bolts and took at the diaphragm but did not see any sort of fuel pump. Just looks like a bunch of metal. That all looked fine. It was running 40 and then lost rpms and started back firing and then died and now wont start. We have had the flywheel off several times and have put it back on the same way and it has ran 20mph and then we had it running top speed and then it died. While we were on the lake we tried to get it going again but it has been the same chugging sound and weak sound we have been getting since we got it back to the house and took the flywheel off and back on again.

Re: 1986 85hp Force Outboard won't get high rpms.

Have you checked the check valves in the fuel pump housing to see if they are sticking? You have to push them several times and look closely as they are so small. They have been known to stick and cause your engine to go lean. They only cost $5 each so I would replace them just because they are so old.

Hope this helps,

John