lower unit help

[idahosweetthing]

I have a 85 forced the the lower unit need replaced. I have found a lower unit from a 125 will it work on my boat.

 

[Frank Acampora]

We really need to know the year of your engine and the approximate year of the lower unit.Up until about 1994, the lower units all use the same bolt pattern and will bolt to almost all late Chrysler and early Force engines. Later Force engines used a Mercury type lower unit and the earlier lowers will not fit. Early Force engines used a different gear ratio for the 85 and the 125. The 125 lower will work in this case but performance will be a bit less.Also, later force engines used a larger water pump. To fuit the lower unit to an earlier Force engine you need to remove some metal from an internal web in the midleg to clear the pump.

 

[jerryjerry05]

He said 85 to a 125 so that precludes any 90's models??
Just make sure it the same size shaft.
Check the gear oil. Be careful of the plug you remove???
It will work , you might have to re-prop.

 

[idahosweetthing]

My 85 forced is a 1988 I did find a used lower unit and we have put it on and it worked well from what I could tell. I used the same prop that the old one had. I took it out and tried it out and it ran good. The only thing is I was not sure what position the put the exhaust in so I place it straight with the prop. I was not sure of the tilt when I was in the water so that's my next thing on my list to learn. And starting it seemed to not want to start with the tilt down all the way so I pulled it up and it would start not sure if that is right or not. I'm really new to all this but with a little help will get it. I can not wait to have fun with my kids on the water this summer.

 

[Frank Acampora]

It is OK to start with the exhaust snout centered. Then, at the speed you normally run the boat, if the boat pulls to the right, you move the exhaust snout at the rear to the right in small steps until the boat tracks straight. Actually, you move the front to the left, because that is where the slot is. Be certain that both bolts are tight to avoid losing the snout.

The exhaust snout is also a trim tab: When you move the back to the right, prop wash and forward motion tend to move the engine left. causing the boat to track straight.

As far as not starting when fully tilted down, I am not sure of the cause. Perhaps someone else has had and corrected the same problem.

 

[idahosweetthing]

Thank you Frank you have been a lot of help this little boat has seem to make me spend more time on the internet than anything. Was think to just take it to a shop but than found out it will cost $100.00 hour just to tell me what wrong. And than a $100.00 hour plus parts to fix. Guy said it would cost about $500.00 to $1000.00 give or take.