97 force 75 elpt lower unit detonated

[syork6197]

I bought a crest pontoon about a month ago, after getting the motor running good the lower unit detonated. I need help. I need to repair it or replace but dont know where to get parts or what is compatible with the motor. Please help
serial # is oe259309 All help is needed and appreciated. Thanks

 

[jerryjerry05]

That year came with 2 different drives.
I think???? either will work for a straight replace.

To rebuild you need to figure out if it's a 3 or 6 jaw unit?
Need pics of the top of the drive on the cavitation plate, the top of the bolt.
Next to that bolt is a square block(3jaw) or a pointed block(6jaw).

Then is it a long shaft 37" or a short 32"??

Figure these things out and then I can figure out what parts or units will work.

 

[syork6197]

The unit is still on the motor, I haven't taken anything apart as of yet. Have to find parts or decide whether or not to replace the whole motor.

 

[syork6197]

I contacted a local marina and they were able to tell me that my lower unit is a 20 inch shaft, didn't say if it was 3 jaw or 6 jaw. However he says he has a used unit for 600 bucks. Should I go with a used unit or try to rebuild or just flat out replace the whole motor?

 

[blackd]

syork6197, Jerry gave you the indicator ( on the top of the drive on the cavitation plate, the top of the bolt.
Next to that bolt is a square block(3jaw) or a pointed block(6jaw).)whether yours is a 3 or 6 jaw LU. Check the used unit to see if the indicators are the same as on yours. If so, I would recommend buying and installing. Have the mechanic test the used unit for leaks, install a new impeller and grease and go. As long as they are similarly geared nothing else is needed, otherwise a different prop may be needed,


If they are different much more work is needed, and the cost will probably exceed any savings.

 

[blackd]

ssyork6197, BTW I have a late model 3 jaw mercury LU on my 1997 120. IIRC, I paid ~$400 for it plus shipping. You need a 2.01 to 1 gear ratio 20 inch LU.

 

[jerryjerry05]

A marina will charge you twice the cost of what it's really worth(my opinion)
Now if they install a new impeller and install the unit?? $600 isn't that bad.