50 force problems- help

[jaycafe]

I need some direction. I have a 50 force on a 15' bayliner (yes its underpowered). Motor overheated a couple of weekends ago. Shut it off as soon as the buzzer went off. Got it home and did a compression test, top was 120, bottom was 100. Whats happening now is its a little hard to start (always started great) and doesnt want to idle at a low speed (always idled great). So to really test it, i put it in the river and revved it up and down some and took off...to find that at full throttle, it was running at "maybe" 1/2 the speed it normally runs at. Half the power! Checked plugs and spark...all ok. I dont know where to look at this point. What can i test? How about the coils not working right?
A couple of notes: I took the thermosat out when it overheated and tested it...coiled up in the hot water. Guess its ok. Left it out anyways.
I didnot replace the impeller...from what im reading, this is a must when a motor overheats, I will replace it.
Thanks for any /all help!

 

[roscoe]

Re: 50 force problems- help

Check compression before spending a nickel on anything else.

 

[jaycafe]

Re: 50 force problems- help

Compression was checked...120 in top and 100 in bottom. I dont think thats bad enough to cause me these probs.

 

[zxthrilla]

Re: 50 force problems- help

im not a mechanic or a very experienced boat person but i know that if the compression is off by that much you need to check the inside of the cylinder walls because you might have a bad situation on your hands. I just had to scrap a motor because of just that.

 

[jaycafe]

Re: 50 force problems- help

What else can i check? When its WOT and only half the power!!! Help help!

 

[roscoe]

Re: 50 force problems- help

Get a Clymer repair manual.
Troubleshoot the ignition.
If ok, check fuel system.

 

[roydongi2]

Re: 50 force problems- help

Youd did not mention what year your 50 Force is. I have an 1985 5o HP Force on a 15' roundabout and only ran half the RPM at WOT. Plugs were good and so was the fuel supply. But always wondered why the plugs were always wet with gas when I take them off. Then I found out that these motors actually have a couple of contact points and a distributor below the flywheel. I downloaded a service manual for six bucks and got the proper gap and now the engine works really well. I had a couple of issues with the flywheel coming loose but that's because I couldn't torque this enough. But finally solved this problem have had fun with the boat ever since. That was just about a little less than two weekends ago.

 

[Banditz]

Re: 50 force problems- help

hey man...Mines a 91 model...if yours is near that then I would say you burnt up the dang head gasket. Easy fix bro...either buy another and switch them out, or get some copper rtv sealant, and remove your head and after you clean everything, reinstall running a bead around the whole old gasket..then torque down from middle out. i know i know,,its not the best way but it works for mine. While trouble shooting my no water issue, I burned the damn gasket four times. had a pressure test of only 80lbs on top and 50 on bottom. Well after doin this mines back up to 130 each. Well 132 on one and 135 on the other. But my point is it works and could be your issue. Very easy o do and takes less than an hour. try it, its almost free....Good luck

 

[kyle f]

Re: 50 force problems- help

20% Difference in compression is not a good thing.

My Buddies 50HP Force (95 Model) we were working on burnt the head gasket and wouldnt even start. He had 125 on top and 50 on bottom.

Definately replace the head gasket and recheck compression.... the try to run her again.

 

[Jeremy90bay]

Re: 50 force problems- help

Agreed about the head gasket. If you keep ruunig it with the bad impeller your going to burn up the engine. Change the head gasket and impeller and enjoy the summer on the lake!