125 Force no power

[stixx]

My Older Bayliner with a 125 force ran OK last Saturday. It had a problem starting again stopping for a swim, but it ran good overall at about 4-5000 RPMs despite having a bit more weight onboard than recommend for part of the ride.
The next day it took a bit to start again, but that may be a throttle positioning problem?
The big problem that day was that it didnt have any power. it ran the same speed when the throttle was full out or @ 1/4. The rpms wouldn't go over 2000.
I plan to use a can of seafoam additive into the gastank, do you think this will help? Any ideas?

I am very new to boating. ..thanks

 

[Jiggz]

What year is this 125HP? For an engine to not hit above 2000 RPM, there would have to be some serious misfiring. Now the question is what do you mean by, "the throttle was full out or @ 1/4"

 

[jerryjerry05]

Sounds like the linkage might be loose?
Do a compression test.
I think seafoam is a waste of $$ That's my opinion. Some love it, not me.
I prefer to get Mercury's Powertune or OMC's Engine Tuner.
Both will help with a decarb.
OI also get Chevrons fuel system cleaner with Tecron. Tall black bottle.
I mix that with1 gallon of gas and the recomended TCW oil in a remote tank..
I run that through the carbs and after a minute of running I shut it off and let it set for an hour.
Then start it up and let it run again for 10-15 min then go back to the boats usual fuel. This cleans out the carb and any build up.

Check the hoses and the fuel pump diaphragm.
Install a filter between the carb and pump. Wally World G-12 or G-2

 

[stixx]

The motor is approx 1989. ( Ill refer to the manual tomorrow)
When I say 1/4 I mean that the throttle was one quarter of the way to full power.
- *** I looked at the carbs and noticed that one of the bowls were still loosened from the winter. I noticed it when I pressed the fuel bulb the fuel leaked out the bottom carb bowl, so I tightened it up. ....
-Ill get some help to clean the carbs next week and check the filters etc.

***Will tightening the carb bowl help the problem ? ** Thanks

 

[Mikkohart]

I had similar issue with my 125 and it turned out to be a problem with stator and high rev area?! Engine worked well one day but next day just would not rev over 2600 rpm.

 

[Jiggz]

So the RPM stays the same (2000 rpm) regardless if the control throttle (NOT THROTTLES) is at 1/4 or WOT. You need to verify the throttles (these are the butterflies on the carbs located down the "throat") using a flashlight and looking into the bore of each carb to make sure the throttles are moving with the control lever or throttle. At neutral the throttles should be almost close and should be in horizontal at WOT or full out or forward.

 

[jerryjerry05]

Never leave the bowls loose.
The cork or rubber seal can shrink and leak.

 

[stixx]

I finally got on the water today. I changed the spark plugs. (The lowest plug was not as darkened as the other three). I also tightened the bowls, added sea foam to the tank a few days prior to going out. The boat started easier. It went a bit quicker but still only about 10 knots at the fastest. I ran for about 20 mins.
I went back to the dock and sprayed the carbs with carb cleaner according to the instructions. It stalled when I sprayed it into each carb, so I revved it up a little. It managed to stay running longer when I did that. I let the boat sit for about 10-15 mins then went out for another ride.
It still didn't run more than 10 knots at the most even at WOT.
-1. any thoughts on why it has no power.?
-2. The throttle cable looks a bit rough, could that be the issue. if so, how much is that part and what would that cost to get replaced ?
-3. Would a poor gasil ratio cause this problem? I run 30:1 as that's what the previous owner did, my father in law.

thanks everyone, keep in mind I am a newbie to boating with no mechanical skills.

 

[Jiggz]

First the fuel mix should be 50:1. Second, inspect the carbs' throttles to make sure they still move in synch with the control lever. With 30:1 fuel oil mix you will constantly foul your spark plugs.

 

[stixx]

*Update* I had the compression tested, it was good. It turned out that one of the coils needed to be replaced. We were able to use one off my extra motor. We took it out for a ride and it started well and ran pretty good at WOT.
It runs better at WOT than it does on the way to WOT. It seems to sort of stutter/shake at about 1/2 throttle. Any idea why that would happen? It also seems like it should go quicker, not sure if it needs a new throttle cable.
I will also try using 50:1 mix vs the 30:1 mix I was told to use and see if that helps with the poor acceleration.

Thanks for your help so far.

Stixx

 

[Jiggz]

Try the 50:1 mix first before further troubleshooting. And make sure you clean the spark plugs as soon as you are ready to try the 50:1 mix.