Force 125 quits after adjusting shift rod - where to start troubleshooting?

[khoonie]

I recently succeeded in adjusting the shift rod on my 1988 force 125 engine. It had been chattering when I tried to put it in reverse, then stopped going into reverse completely. I consulted this forum and learned how to adjust the shift rod; after doing so the engine would shift cleanly into reverse, but it would die and have to be restarted. So I adjusted the idle speed and was able to shift cleanly in and out of reverse as well as forward and the engine idled perfectly and was running better than it ever had. The next time I took it to the lake, it shifted and ran fine at the dock and also ran fine as I pulled away. However, about a minute into my full-throttle run, the engine suddenly stopped dead: the backwash flooded the back of the boat it was so abrupt. I tried restarting and it cranked, but only very, very slowly, as if the battery were dead (it was not). When I got it back home (I had a 5 hp kicker, TG) I put it in gear and tried turning the prop. It would turn, but only with great resistance and it made a slight metal on metal noise when I did so. I am afraid my gears are damaged, but I am not sure. My question is: what should I do first in order to isolate the problem? If anyone can offer some advice here, I would appreciate it very much, as I really don't know where to begin. I thought perhaps there might be some kind of "troubleshooting protocols" based on initial symptoms....

 

[Jiggz]

When you decided to place it in gear and turn the prop by hand, did you have the plugs out? If not, yup manually turning it in this condition will be very hard as you are opposing cylinder compression. The metallic sound is concerning. So you might as well drop the lower unit (LU) and place it upright on a vise or something to hold it up and then try manually turning the prop or shaft both in fwd, neutral and reverse and report if there is still metallic noise or if it's still hard to turn.

 

[khoonie]

Ok. Thanks, Jiggz. No, the plugs were not out - I knew about the compression resistance, however. I cannot work on it today, but as soon as I do I will let you know what I find. I have never dropped the LU before. Should I just buy a Clymer manual or is it relatively simple? (or maybe it is already described in a sticky or elsewhere)... I will check.... One other question, though. Even if the gears are/were damaged, if I put it in neutral and try starting it, shouldn't it start? It would not start when in neutral right after this happened. It would just barely turn one or two times, grudgingly, as if the battery were dead. I tried turning the flywheel by hand and it was very hard to turn too. Don't know if this info is pertinent, but I thought I should mention it. Thanks.

 

[Jiggz]

There is a sticky post on the top of the forum for replacing the impeller which involves dropping the LU. Follow this procedure to drop your LU. From here you can do inspection of the drive shaft. Before doing so test the powerhead. Activate the killswitch and try cranking it over. Does it crank over easily? If not, remove the plugs from the powerhead and try rotating the flywheel by hand. It should be very easy. If not then there is a problem in the powerhead, meaning you would need to remove the head and do an inspection of the cylinders. If it is easy to rotate move on with the inspection of the LU. Inspect the impeller, bearings and if everything looks OK, then it is time to look inside the gear housing.

 

[Frank Acampora]

It also may have thrown a ring. With the lower unit removed try turning the flywheel by hand (with the plugs out) Anything other than slick-as-snot smooth turning means you need to remove the head and inspect the pistons.

 

[khoonie]

Okay! Thanks Frank and Jiggz. I will get on it as soon as I can. At least now I have a plan to follow. I will post again as soon as I can. Your help is greatly appreciated.