1978 Evinrude 25hp lower unit replacement

[mike__b]

I'm looking at a 1978 (trying to confirm that) Evinrude 25hp that needs repair in the lower unit. Can anyone explain what other lower units would be compatible (1975-1985?)? I read that 77 and 78 had different sized components related to the drive shaft / gears. If I replaced the whole unit, drive shaft and all from a 75-85 motor, would that work on a upper unit? Do most salvage places carry used gears, etc if I just wanted to repair the existing unit? It falls out of gear while on the throttle...

 

[78 mckee]

Re: 1978 Evinrude 25hp lower unit replacement

Sounds like a worn clutch dog, output shaft, or forward bearing. you would have to disassemble to inspect and determine the cause. Other years may fit but you'll have to investigate. Just try looking at the parts discription on the Evinrude website to determine compatability of different years by comparing the component part numbers to that of your motor. I have purchased good, used lower units from Ebay sellers, you just have to figure out what fits. There were changes to the drive shaft over the years so investigate carefully.

 

[dew2]

Re: 1978 Evinrude 25hp lower unit replacement

I think 1978 was a new cutoff year a 1977 and earlier wont work.One way I find what your asking is go here (Below) type in a lower unit gear forward and reverse number the dog and it will give models and years interchangable on the right hand side of the site.
I hope it still does the site was down a few days last week and its been changed abit.Here it is
http://www.boats.net/parts/search/parts.html

If you can find the part number of the whole assembled unit put it in.. I never found a whole unit number????? reason I said put different parts # in GOOD LUCK