Drive Shaft has been cut and sleeved?

[inim_repooc]

been trying to get the lower unit off of my 1990 40hp mercury 4 cylinder for a while today with no luck - the drive shaft is obviously stuck in the powerhead. After a while messing around - I noticed 2 rivets in the leg near the top... I investigated and after sanding the area down I found a plate covered in filler covering a large hole that had been cut in the leg! it appears that the shaft has been cut from here and it is now slotted into a tight fitting sleeve and secured with 3 grub screws!

have any of you heard of this type of repair before? It does seem to have been done very professionally... just interested and I'm wondering if it will be strong enough?

I'm also pulling the powerhead off, so I will try to free the drive shaft from it and hopefully just put the sleeve back together, cover and fill over the hole in the leg and hopefully not need to sand and paint the leg each time I take the lower unit off!


Thanks

 

[Scott Danforth]

Post pictures of the hack job. I wouldnt trust it and would get a replacement shaft off of ebay and rebuild the lower and get the mid section welded up

 

[CV16]

I'm with Scott, I wouldn't trust it.

 

[gm280]

With the amount of serious torque on that shaft, I wouldn't want to be taking the boat out anywhere I couldn't see land. You never know when it will snap off leaving you stranded. Either buy a new, used or if you can find either, have a machine shop make one. Splines are not difficult for a machine shop to make. JMHO

 

[Chris1956]

OK, so they cut the driveshaft to get the gearcase off. Maybe they were still unable to get the driveshaft out of the crankshaft, so they just sleeved it?

I hate that...

 

[James R]

There is a lot involved in correcting the problem. You may need to cut the shaft again to separate the power head from the lower unit. To remove the drive shaft stub from power head the crankshaft will have to be removed, mounted in a vice and heat applied. Possibly two vice grips on the shaft stub and careful application of a soft face mallet. With all this it may still not come out. So if you want to save the beast, replace the crankshaft and the drive shaft , or replace the lower unit. While your at it you might want to consider a rebuild. Another motor may be your best bet. So sorry for your predicament.

 

[BLKBEARD]

If you pull off the power head,and find the driveshaft stuck. You can make a puller to remove the section of shaft stuck in the bottom of the crankshaft as follows.

Cut the driveshaft off about 3" below the crankshaft
Drill & Tap a hole as large as possible, and as close to center as possible. 3/8, 7/16 etc.
cut a piece of pipe that will fit over the shaft of your bolt and rest against the bottom of your crankshaft. The pipe sleeve must extend past the end of the driveshaft by an inch or so.
Thread a grade 8 bolt with a flat washer & nut through the pipe.
Hold the bolt steady with a wrench while cranking down the nut with another wrench.

This should effectively pull the driveshaft section from the crankshaft without heat which may damage the crank seal, and without beating on it with a hammer.
you can also put a brass flat washer between the pipe sleeve and the crankshaft for added protection of the splines and crankshaft end.

Soak it well with a good quality penetrating oil.

Hope you don't find any further surprises.............................Best of luck

 

[gm280]

I noticed the OP has not come back with any response so I don't know if additional ideas are warranted. :noidea: Usually a problem posted has responses to questions and even posted pictures. I don't see either. JMHO