Force 120 hp problems

[mrbongo]

JUst bought this boat and motor and have some serious problems I'm afraid.

It was running okay but seemed to hiccup a couple times. Tried to get up on plane and it sounded like something was hitting the prop.

I turned back towards the marina and slowed down to a troll to take it easy. Sounds started getting worse and then it died. Really sounded like
something hitting the prop. I tried to start it again in neutral but it wouldn't turn over.

Made it home and now the engine won't turn over even in neutral. I checked the lower unit and water came out. No gear oil. Put some in and it
finally came out the drain hole and has some very small bits of metal shavings. Prop was not hit. Looks fine.

Prop won't turn, engine won't turn over even in when in neutral.

Any idea what I've done? I am actually hoping that I just ran the lower unit dry and it locked up.

Thank you for any advice.

 

[jerryjerry05]

Re: Force 120 hp problems

Drop the lower.I'll bet that it's locked.
After it's dropped then start the motor.
The drive should have some kind of oil.
Try to take it apart.If you just bought it the guy probably sold it to you with NO oil.Take it back.J

 

[bentle]

Re: Force 120 hp problems

After removal of lower leg. If you start it at that point you don't want your motor to run any longer than 15-20 sec. at most or you will over heat your motor. It would be best if you only turn it over and not let it run at all.

 

[mrbongo]

Re: Force 120 hp problems

Thanks for the quick responses!

I'll try to drop the lower unit and see if it will turn over. I think it probably had little or no lube in it. I feel like I should have checked it out but he said he had it ready to go. I'll only start it for a few seconds if I really have to.

It just poured water out of the drain. After I put some gear oil in it it started coming out with very fine metal shavings.

 

[bentle]

Re: Force 120 hp problems

Your most likely looking at either rebuilding or buying a lower leg for your motor.
Running that long without gear oil and with large amounts of metal draining out is a sure sign of a rebuild or replacement part. That gear housing and gears need the gear oil for proper lubrication of its moving parts. If you don't have the know how or patience for a rebuild then go with a new gear housing, or take it back.

 

[mrbongo]

Re: Force 120 hp problems

Okay, pretty much decided to try and replace the lower unit. I'm going to pull it off and try to start the engine for 10 seconds to see if it's okay.

Assuming that it starts and hasn't seized up, can anyone tell me what range of HP and years of lower unit will work on this outboard? I think it's a late 80's
Force. I just saw a 85 HP lower unit on ebay.

Thank you all for your help.

 

[bentle]

Re: Force 120 hp problems

As long as the 85 doesn't say force by mercury then it should be fine. Not alot of difference in horse power between the two.

 

[mrbongo]

Re: Force 120 hp problems

Lower unit is off now. The engine turns right over and seems like it wants to start. Didn't start it but I guess I should just to make sure.

Shaft into lower unit has a coupler and the long part comes off. Does that mean it's a two piece shaft? Model number is 1201X91H. Guess that means its
a '91 from what IVe read.

Think should tear into the lower unit and see what happened? It won't turn at all. Seems like it's locked up.

 

[bentle]

Re: Force 120 hp problems

Yes the 91h at the end of model number is how you would identify the year. Not 100% sure but 1980-1989 prob. will not fit your motor. Does your cowl cover say force by mercury on it anywhere?

 

[mrbongo]

Re: Force 120 hp problems

It says US Marine. No Mercury anywhere I can see.