20hp mercury, broken drive shaft

[fishnforfun]

I have a 1995 20hp mercury with a broken drive shaft. I am trying to remove the prop shaft and gears so I can get the drive shaft out of the lower unit (already off motor) I have removed the prop, a spacer and 3 screws holding a plate on there and now I am not sure what else to do. I have ordered a manual but it has not arived. I forgot to mention that the prop shaft is siezed and will not spin, I think this is why the drive shaft broke.
Anybody that can give me a little info would be greatly welcomed.

 

[carholme]

Re: 20hp mercury, broken drive shaft

Here is the service manual for that engine:

http://1manual.com/Mercury manuals/Service Manual PDFs/TwoStroke/826883r2/cover.pdf

You must have Adobe Acrobat reader installed to use this manual. If you scroll down to the lower part of the opening page, you will see the various engine components in red. Click on the one you want and when the first page opens, click on the "Save As" icon at the top LH corner of the page and you can save it to your computer.

Sounds like you are at the stage where you want to remove the bearing carrier. See Page 6A-14 and you will see the tool you must purchase or make.

Gerry

 

[fishnforfun]

Re: 20hp mercury, broken drive shaft

Thanks! I wish I had seen that before I paid for the one I ordered.

 

[Mi duckdown]

Re: 20hp mercury, broken drive shaft

Fish. having the the book is not a bad thing. In fact i like them better. Money well spent. That way I can read them in my easy chair.
When you take things apart take take pics and document. Shims taken out, most of the times go back in the same order.
Just a thought for you.

 

[fishnforfun]

Re: 20hp mercury, broken drive shaft

I have never taken one of these apart before. I have laid out some paper on the bench, every part that comes out is going to be numbered and placed in order. I want to be sure that it all goes back together the way it came out.

 

[fishnforfun]

Re: 20hp mercury, broken drive shaft

BTW, while I am here, has anyone got an easy trick for getting the small broken end of the shaft out of the motor end? I hadn't realy thought of how I will do that. I figure the manual is not going to describe how to get a broken drive shaft out.

 

[Mi duckdown]

Re: 20hp mercury, broken drive shaft

Fish. Good Idea. That is the best way to learn. Need help? keep posting.

 

[Mi duckdown]

Re: 20hp mercury, broken drive shaft

Fish can you supply Pics? Of whatever is broken???

 

[fishnforfun]

Re: 20hp mercury, broken drive shaft

I will try to get some pictures on here when I can. The part that broke is the drive shaft. It is sheared off at or near where it goes into the motor.
I have not taken the casing that is below the motor pan. I am not sure how much if any of the shaft is below where it slides into the splines at the motor. I am hoping to get to that part of it later tonight or after work tomorow.

 

[Mi duckdown]

Re: 20hp mercury, broken drive shaft

Ok you have removed the lower unit?? And the shaft is broken? Yikes.

 

[fishnforfun]

Re: 20hp mercury, broken drive shaft

exactly what I thought when I saw it YIKES! Anybody know wher I could find a complete lower unit for a reasonable price? Just looking for a second option in case I can't fix this one.

 

[carholme]

Re: 20hp mercury, broken drive shaft

Here is the parts listing for your engine:

http://www.crowleymarine.com/mercury-outboard/368.cfm

Gerry

 

[Mi duckdown]

Re: 20hp mercury, broken drive shaft

Fish. would still like to see Pics If you don't Mind. I have never seen a drive shaft snap. That is the strongest(SP) Part of the motor under the crank.
Seen twisted prop shafts, that amazed the heck out of Me.

 

[oldman570]

Re: 20hp mercury, broken drive shaft

Several salvage yards are listed in a sticky here, at the Johnson Evinrude forum, where you could find a use LU for your motor. If you can not turn the driveshaft in the LU you have, chances are not good that the gears are damaged also. Check all parts for Any damage before making any purchase.
Oldman570