How to dismantle lower unit

[Keith Buchanan]

1989 50 HP 3 cyl.<br /><br />Hi guys, after gear failure I have undone everything on the gearcase, removed the gear shift shaft and pump housing and still the driveshaft and propshaft will not pull out. I presume the crank driveshaft has to come out before the prop shaft will move. Is there a trick to get these out.<br /><br />Regards Keith B...

 

[Barnacle_Bill]

Re: How to dismantle lower unit

The prop shaft has to come out first. It may be a bear. I think there is a snap ring that has to come out first. After that is out, there is a nut on the bottom of the pinion gear. (Way up in there). Remove that and the drive shaft will come out. Good luck!

 

[Keith Buchanan]

Re: How to dismantle lower unit

Gotcha, thanx for that. I didn't want to force anything without knowing. Got it all apart now.!!<br /><br />Anybody give me any tips on using a calculator, I think I will need one.<br /><br />This looks expensive....Keith B.......

 

[Keith Buchanan]

Re: How to dismantle lower unit

Gotcha, thanx for that. I didn't want to force anything without knowing. Got it all apart now.!!<br /><br />Anybody give me any tips on using a calculator, I think I will need one.<br /><br />This looks expensive....Keith B.......<br /><br />Just realised I've posted twice sorry guys gotta get my rating up somehow......

 

[achris]

Re: How to dismantle lower unit

Tried that myself and realized it's a bit smarter than that. Doesn't give you another credit for sequential posts. Bugger.....<br /><br />Chris.

 

[jimmbo]

Re: How to dismantle lower unit

Mercs lower units generally have to have gearmesh and backlash checked and adjusted when parts are replaced. Service manuals explain the proceedure. Not checking/adjusting can result in premature failure of the rebuilt gearcase.

 

[Keith Buchanan]

Re: How to dismantle lower unit

Cheers Jimbo. Is that why some lower units have more shims in than others. I definately need a new pinion gear, it,s dropped a tooth, everything else looks fine. Original part number for pinion gear is 43-88019 and apparently this item has been superseeded to 43-88019T. Any ideas where I will get one of these in the U.K.<br /><br />Thanks Guys..