'85 Force 50 no power

[djastram]

My 1985 Force 50 has no power. It will idle, but if I try and throttle up, it dies instantly. If I let it idle, it will start to miss, and then "pop" through the exhaust and stop spinning instantly. It's not as it is if the key shuts the engine off and it slowly spins down, but it "pops" and stops spinning almost instantly.<br /><br />I've checked for fuel at the carb, and that seems to be good, and I've put new plugs in it.<br /><br />When I check the plugs for spark, it seems as if the spark gets stronger and weaker until the spark is gone for a second, and then returns strong and goes weaker. This appears to be the case on both cylinders.<br /><br />Help! Please.

 

[SlowlySinking]

Re: '85 Force 50 no power

Hi, this is just a guess from 1000 miles away. Seems Force used two different ignition systems, one with terminal strips and one with plug in connectors, based on the "When I check the plugs..." comment I suggest you check the easy stuff first like the ignition system connections, possibly bad/dirty/corroded terminal connections or corroded connectors. It could also be a weak ignition switch, do a key wiggle test and see if that causes a problem with the engine running. Many intermittant problems are caused by bad electrical connections. Good luck and come back with what you find.

 

[djastram]

Re: '85 Force 50 no power

Tried your suggestions, everything is snug.<br /><br /><br />Anybody else have any ideas?

 

[nmbr1ddy]

Re: '85 Force 50 no power

I am having a simalr problem. Runs fine at idle and then boggs down when i get to about 1/3 throttle. Has anything worked for you?

 

[eurolarva]

Re: '85 Force 50 no power

When motor starts to bog down try goosing the choke. Does this improve it or kill the motor? If motor improves it is probably fuel related. If it kills the motor you probably have ignition problems. Verify you are using the correct plugs. If spark is weaker then gets stronger I would be looking at coils or cd units or the trigger. If it is popping or backfiring you may have a busted flywheel key and your timing is slightly off. If key is cracked it can throw the timing off enough to cause it to backfire. The problem is the flywheel can be a bear to get off so hopefully you have a pretty good idea what is wrong before you take it off.<br /><br />Good luck

 

[djastram]

Re: '85 Force 50 no power

Well, I replaced the diaphram in the fuel pump, and put new plugs in it, and now I have the same problem nmbr1ddy has. Mine will start and idle ok, and once your past 1/3rd throttle, it runs like a watch, and has good power. I ran a can of seafoam through it, and it still has the same issue below 1/3rd and above idle. <br /><br />When I start the thing, it seems to idle very slowly and irregularly, and I hit the choke for a half second, and the idle comes up and runs good.<br /><br />A co-worker said it sounds to him like it is an open in the wiring going to the magneto, and as the mag advances with the throttle, the open "opens" and shuts down.<br /><br />The backfiring seems to be gone now also.<br /><br />I'm gonna run it for a while yet, and see if it goes away as quickly as it appeared.<br /><br />Thanks to all who have replied so far.

 

[eurolarva]

Re: '85 Force 50 no power

djastram you might want to start a new thread. It is confusing having two different things going on in the same post. However I suggest you look at your carbs again. If the choke improves the condition of the motor it is in the fuel system. I would recheck all the small orifices in the carb. Did you clean or rebuild. If just cleaned get a rebuild kit and do a detailed job. Go after all the small openings with a wire and carb cleaner then blow out with compressed air. Check for a potential air leak. The oring connection for the quick disconnect for your gas can. Recheck the pump bulb and all fuel connections. Last you should replace the fuel seats and gaskets in the fuel pump. I read another guys thread about his problems with his old chrysler and he had to replace two of the three seats. If you go this route post it and I will give you part numbers for the seats and gaskets. You will need to post your make and model number.