Loud Force 120 during Idle/low speed

[scottdNH]

This Saturday I went out off shore about 30 miles out. Once we were out fishing I noticed the impeller was spitting at a much lower rate than usual. But it kept spitting water. Almost right after I noticed that The motor got VERY loud, almost as if a car was driving around without a muffler. In slow speeds or while idling it sounded HORRIBLE! When I opened it up to get back to shore it seemed to work fine, speed was right up where it normally will travel at, around 25-27knots. As soon as I got back in to the harbor to slow down in the no wake area the loud noise came right back. It never over heated, The water kept coming out of the impellor hole and placing my hands on the motor it wasn?t hot at all even after the 30 mile trip. Once I got it home and went to clean it up and run fresh water through it to clean it out just as loud as it was on the water. I have dropped it off to be looked at, but they can?t check it until later this week. Any ideas? I have a feeling this is going to be BAD!! Its a 1996 Force 120.

Thanks!

 

[moparman]

Re: Loud Force 120 during Idle/low speed

possibly lost your exhaust plate gasket or cracked the plate itself, as these motors have a tendency to do either or sometimes both. MOPARMAN

 

[scottdNH]

Re: Loud Force 120 during Idle/low speed

Well my boat shop says I somehow snapped my crankshaft. He has no idea how, but I was able to drive almost 30 miles home with it in that condition and he doesnt think it caused any other damage??? Any clue how the heck I could of done that??

 

[Jeremy90bay]

Re: Loud Force 120 during Idle/low speed

Get a second opinion. There is NO WAY your motor would have ran with a broken crank shaft. The crank is what moves everything in your motor. Also how did he determine this with out disassembling the motor. It kind of sounds like he is blowing smoke but thats just my opinion.

 

[pnwboat]

Re: Loud Force 120 during Idle/low speed

Something doesn't sound right with that diagnosis. I agree with Jeramy90bay. Highly unlikely you would be able to run the motor with a broken crankshaft. Did they disassemble the motor?

 

[scottdNH]

Re: Loud Force 120 during Idle/low speed

He got that diagnoisis by just being able to lift the flywheel, it is moving up and down vertically. They are taking apart the motor today to confirm the issue. He did say he cant imagine how the heck it would of worked to ge tme back and after doing this type of work for 30 years he had never seen that.

I totally agree that I thought it would be impossible to drive back that far with a broken crankshaft. He checked the pressure on all 4 cylinders and all are solid with no loss......I'll know more today.

thanks for your input guys.

-Scott

 

[pnwboat]

Re: Loud Force 120 during Idle/low speed

What ever it is, it's probably not very common.

 

[scottdNH]

Re: Loud Force 120 during Idle/low speed

Whatever it is, I know my pocket is going to be a lot emptier :-(

I'll post an update when I know more.

 

[scottdNH]

Re: Loud Force 120 during Idle/low speed

Last night I was talking with a friend down at my football practice telling him about my motor problems....another guy overheard us and said it sounds more like a broken crankshaft bearing as opposed to a broken crankshaft, which as we have all pretty much determined wouldnt of allowed the boat to be drivable at all. Anyone ever break a bearing before and could tell me the results?

Im still waiting on the repair shop to get back to me on the offical diagnosis.

thanks again!

 

[scottdNH]

UPDATE Re: Loud Force 120 during Idle/low speed

UPDATE Re: Loud Force 120 during Idle/low speed

Well here is the final update, the crankshaft did in fact break. It broke up near the top where it connects to the flywheel, thats why it was able to still run. UNREAL!! Today I begin my search for a new crankshaft, no other damge at all, so I was lucky in those regards.

-Scott

 

[pnwboat]

Re: Loud Force 120 during Idle/low speed

WOW! Unbelievable. I sent you a PM.