1985 Force 125 power cuts out

[PESKY1]

Does anyone have any ideas? Still waiting for a reply.<br /><br />Hello, I have an intermittent power problem that I'm having trouble diagnosing. Starts right up, idles nice. First noticed when driving WOT. The engine slows to 1/2 power as if 2 of my 4 cylinders are not working. 5 or 10 seconds later, it will resume full rpms. It does this back and forth every 10 seconds or so. If I pull back on the throttle and drive say at 1/2 speed, it will still cut out to a slower rpm and jerk back and forth between them. Tough to diagnose. I replaced the stator 2 years ago. When it went, I had no spark on 2 cylinders. Reversed wires and spark changed to the other 2. Can stators have intermittent power issues? CDI intermittent issues? Fuel pump not sending enough fuel to 1 of my 2 carbs? Please help.

 

[roscoe]

Re: 1985 Force 125 power cuts out

Hello in Hudson, welcome to iboats, sorry for the wait.<br /><br />I would look for a fuel delivery problem.<br />Maybe a fuel pump diaphram, but more likely a carb problem.<br /><br />A dirty sticky float, or a a bad inlet valve will severely affect fuel reaching the carb when needed. When the carb needs fuel, the float drops and actuates the inlet valve which allows fuel into the carb, filling the float bowl. When the fuel in the float bowl is used up, the cycle repeats itself.<br /><br />If the valve is partially plugged or the float is not moving freely, it will not fill in a timely manner, and could cause the surging you describe. When those 2 cylinders don't get the fuel they need, they are not getting any oil either. This can cause severe damage and cause the engine to run hot.<br /><br />A carb rebuild is in order. You should order up a Clymer Force repair manual, and some carb rebuild kits from your local Mercury dealer, and get to it. Get a can of Seafoam engine cleaner, it will work to clean up the carb, and doesn't smell as bad as the harsh carb cleaners made for cars.<br /><br />Not a bad idea to put a fuel pump diaphram and new fuel lines while you are at it, as these things go bad after 20 years.<br /><br />Let us know how you make out.

 

[Scaaty]

Re: 1985 Force 125 power cuts out

Sorry Roscoe..........this is the classic Stator gone bad. Yes Pesky, you need a new Stator, and maybe a PowerPack. Been there, done that.

 

[roscoe]

Re: 1985 Force 125 power cuts out

Could very well be Robby, but have seen the same from a partially plugged needle valve or a stuck float. Its a lot cheaper to to do a $35 carb rebuild than to throw a several hundred dollar stator at a problem that may or may not exist. I don't throw $ into electric components unless I can test and verify which ones are bad. This will be pretty hard to do if the problem only pops up at higher rpm.<br /><br />Process of elimination. Do the cheap and easy stuff first, especially the stuff that should be done as a maintenance item anyway.

 

[PESKY1]

Re: 1985 Force 125 power cuts out

Thanks for the response guys. I have a manual and rebuilding the fuel pump and carbs wouldn't be a problem. I do fog the carbs before winter and this engine has run great without a problem since the new stator 2 years ago. Still a little confused though. Robby, are you saying the stator and power pack could exhibit intermittent outages? Is there a way to determine which is at fault? When I checked the stator, both leads had 365 resistance.

 

[sam6868]

Re: 1985 Force 125 power cuts out

I tend to agree with roscoe. I had similar issues with my engine. The giveaway is if there is flooding in one of the carbs. This caused intermitent power loss. The reason was an obstruction that did not allow the float to work properly. It was small piece of metal which I removed with a tooth pick. Cheaper mstill than a rebuild. Good luck

 

[Scaaty]

Re: 1985 Force 125 power cuts out

Originally posted by PESKY1:<br />. The engine slows to 1/2 power as if 2 of my 4 cylinders are not working. 5 or 10 seconds later, it will resume full rpms. It does this back and forth every 10 seconds or so. If I pull back on the throttle and drive say at 1/2 speed, it will still cut out to a slower rpm and jerk back and forth between them.

Yeah, this is a classic carb issue. Right. So, fine with me....... rebuild the carbs until the cows come home. When ya get done, go get a stator. And send me/us an update. I'm 99% sure I'm right, but what you do is your choice

 

[Scaaty]

Re: 1985 Force 125 power cuts out

Originally posted by roscoe:<br />throw a several hundred dollar stator at a problem that may or may not exist.

Roscoe, all you need is a $25 inductive timing light...hook it up to the different cylinders and through a process of elimination, if the light stops flashing the same time ya lose power....................bingo. If you switch power packs, and spark loss moves with it, its a a pack, if not the stator,.

 

[PESKY1]

Re: 1985 Force 125 power cuts out

Hi guys, I finally got a kit to rebuild the fuel pump. Didn't do it though. I believe I need a stator. While warming up the engine for a compression check, I noticed a smell like something was burning. This is coming from where the blue/brown lead wires are coming out of the stator. It turned the white plastic shield around the windings black. It was hot, the black wipes off like soot and smells burnt. I assume this means it is indeed the stator giving me the problem. Do you agree? Other questions: Is there something else I should look at that is causing the stator to fail like this? Remember, I replaced it 2 years ago. Shortly after that, I had to replace the regulator. Had no problem since until now.<br /><br />My compression check showed (starting from the top) roughly 122, 122, 122, 102. The manual says it s/b between 145-165. Are my readings acceptable for an engine 20 years old? It has been running without any problems.<br /><br />Sorry this is so long, I appreciate all your help.<br />My 3 questions: Replace stator? Anything else to check? Is my compression acceptable?<br /><br />I'll hold off ordering the stator until I hear from you. Thanks again guys. Pesky

 

[PESKY1]

Re: 1985 Force 125 power cuts out

I meant shortly after replacing the stator, I had to replace the rectifier. Sorry.

 

[PESKY1]

Re: 1985 Force 125 power cuts out

Thanks to roscoe, sam6868, and Robby6950 for helping with my 1985 Force 125 that was cutting out. Robby6950 was correct in identifying the stator problem. When I took it off, it looked as if it has been in a small fire! Put new one on and had a terrific day on the water today!! <br />Thanks guys, you're absolutely the best for taking time to help us out.<br />Pesky1

 

[roscoe]

Re: 1985 Force 125 power cuts out

Hats off to Robby, and congrats on getting it fixed.<br />Compression is a bit low on #4 cylinder.<br />A good thorough DeepCreep decarb may help if it is a stuck ring.