1984 Force 125 - Surging badly over 3000 RPM

Hi All and thanks for giving this a read. I have had a couple great years out of this motor but this summer something new has come up.
Will cruze great at 3800 to 4000rpm, then one day its like someone was playing with a fuel shut off - loss of power down to about 2500rpm - surging back up to 3000rpm and back down again. Shut the motor off - restarted and it was fine for the rest of the day.
Same thing happened last weekend but over 3 days the problem is constant now. Runs fine up to 2800rpm maybe 3000 but as soon as it goes over that the surging starts.
Replaced the Pump bulb - cleaned out the fuel screen - checked for any obvious hoses or wires that might have worn through - all appear good

I have gone through all the other posts and the main things i need to check are the fuel tank vent line, fuel pump diaphram, stator and CD boxes for loosing voltage, possible rectifier and last but not least the trigger.

Really hoping that someone else may have had the same problem and can steer me in a direct path rather than ripping it all down - there was one person that had the same problem but he hasnt responded back yet so what can hurt by throwing it out there.

Cheers to all and thanks for givng this a read - any help would be greatly appreciated

Rich

Re: 1984 Force 125 - Surging badly over 3000 RPM

Finish your check list and come back. Most likely fuel vs elec.

Re: 1984 Force 125 - Surging badly over 3000 RPM

In the tank the fuel pick up might be clogged.Some have a screen installed.Or it could be clooged with varnish etc.
The fuel tank vent line:bugs just love to build nests in them.
Next or first.Compression/spark tests(just in case) then rebuild the fuel pump.
Clean the carbs,replace the rest of the hoses and any filters in the system.
Install a filter between the carb and pump.J

Re: 1984 Force 125 - Surging badly over 3000 RPM

Thanks for the info - i should have some time this weekend to really dig into the issue - found so far on a quick look was neutral safety switch wire was loose and plugs were alittle fouled. Your right on checking the gas tank though - I did find some crud in the engine fuel screen. When i first got the boat - cleaned out the old fuel, cleaned the tank and replaced the sending unit but failed to check the actual fuel pick up. Searching some posts last night found a pic of what the pick up could look like after years of use. Will give an update after the weekend.

Cheers and enjoy the sun

Rich

Re: 1984 Force 125 - Surging badly over 3000 RPM

I own a 89 force outboard 125 and just found out that the wires coming out of my trigger have
a short in them and right where they come out at the base to. I didn't even notice until I moved
Them tiny things and got the same symptoms as you
described. when I say moved them I mean very lightly so as not to pull on them. Got a new
trigger on its way though. Good luck.

Re: 1984 Force 125 - Surging badly over 3000 RPM

These problems can be maddening sometimes. Before your fuel pump in the cowl place a cheap clear fuel filter. While it will trap the junk in the fuel it will also tell you if you have an air leak in fuel lines or if the fuel pump is not keeping up. It will even show you if you have water in the fuel. Not bad for a $6 item.