92 Force 12 overheats at slow speeds

[kjkozak2]

Greetings!

I finally got my motor back together (2 new pistons, new rings all around, head gasket, new impeller). I ran it around all day Saturday towing skiers, wake boards, etc... and had no problems whatsoever. Sunday I cruised the lake at "slow no wake" speed and it overheated. I cooled it down, cruised again and it overheated. The alarm never went off, but it was HOT and a lot of steam was coming out of the tell tale.

I think I have the impeller in right (vanes bent backwards with rotation) and there is water coming out the tell tales. I tested the thermostat in hot water and it works great. The carbs haven't been adjusted since I bought it in 93 and I'm sure I used the right oil/fuel misture. I'm at a loss.

Here are my questions:
Any idea why it would overheat at slow speeds and not at WOT?
Would running it without a thermostat harm the motor?
Is there any way to check if the water jackets are clogged?
What else might cause this problem?

I searched this forum but found nothing similar to what I have, and I'd really like to figure this out by the 4th. Any help would be greatly appreciated!

Thanks in advance!

Kevin K.

 

[Tommyd327]

Re: 92 Force 12 overheats at slow speeds

Mine was doing the same thing last week. When I got home I pulled the lower unit to check the impeller and the plastic housing over the impeller was cracked and the gasket one the bottom half of that metal plate was torn. While I had it off, I replaced the gaskets, the impeller, and the plastic housing. The water was coming out of the holes before I replaced the parts but it must not have been quite enough with some water escaping though the gasket and cracked housing. Runs perfect now!!
My motor is a 93 Force 120.

Hope it helps.

 

[kjkozak2]

Re: 92 Force 12 overheats at slow speeds

Thanks Tommyd!

I just pulled the LU and took the pump apart just to make sure I had it together correctly. I noticed that the washers for the 4 studs/lock nuts were between the gasket and the plastic cover instead of on top by the lock nuts. (Total bone-head move on my part). That would certainly reduce the water pressure to the power head if all the water was spewing out the sides of the pump. I feel like such a tard!

Hopefully that was the problem. I'll know as soon as I put her back together and test it out.

Thanks again!

K.