lower unit is it good or bad?

heyitstim

Cadet
Joined
Jul 6, 2002
Messages
18
After fixing one problem there is a new one. my 65 hp mercury shifts into forward gear fine, neutral is ok to, but when you shift into reverse it makes a grinding noise and has very little torque, will hardly move the boat backwards. I checked the shift cables, the problem wasn't there, I removed the cable and changed the gear by hand, forward gear engaged fine, neutral also, but when I pulled the shift rod back to put it in reverse it started grinding. It does engage into reverse but still makes that noise but has no torque. I feel the problem is in the lower unit. The other problem I have found is water is getting in the lower unit. Is it worth trying to rebuild or should I look for a salvage or new replacement. Or just keep running it with foreward gear only after I stop the water getting in the lower unit. <br /><br />I do believe the old saying " The best days of boating are the day you bought it and the day you sold it" Thanks Tim
 

petryshyn

Commander
Joined
Oct 3, 2001
Messages
2,851
Re: lower unit is it good or bad?

Could be a piled up roller bearing in the forward gear. You'll have to take it apart to see if its worth repairing. Draining the oil may confirm grindings.....
 

maked

Cadet
Joined
Aug 16, 2002
Messages
20
Re: lower unit is it good or bad?

gidday <br />having nearly completed a part by part strip down and rebuild of a little merc, a couple of things spring to mind., you may have a shot bearing or several but you will have to take her apart to see. I dont know how old your motor is but if it is 70s to 80s or there abouts, check the oil in the gear case, if its creamy, water is getting in and I would hazard a guess that the drive shaft assuming it is steel is severely pitted between the top and bottom seal of the waterpump housing causing water to leak through the bottom seal and into the gearcase. If this is your problem, you will have to strip out the gearcase clean out bearings etc, replace whats shot and get an engineer to build up the pitted area of driveshaft with stainless steel and mill it back to spec. My engineer over here will do it in about an hour so at approximately $25 US it is a much cheaper way to go than a new driveshaft. have a look and keep us informed (ps use a manual if you doing a major disassembly, there is an order)<br />good luck ;)
 
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