1977 Evinrude 25 clutch question

I am rebuilding a 1977 Erude 25. The clutch dog is worn pretty good on fwd side (was jumping out of gear) I was told you could turn dog around and put the worn side towards reverse. Is this true?
Great forum by the way

That was true in the days of yesteryear (1950's/1960's), however as technology progressed it was no longer possible.

Look closely at that shifter dog... there should be some indication on it that coincides with having it installed one way only as per a service manual, one end marked Prop End or circle (a groove) imprinted on and encompassing the face of the dog.

On your model, the indication would be a groove on the face of the dog and that groove must face forward. To install it backwards would have the engine jumping out of gear even if the dog and gear were new.

Note that to install a new dog... with a used gear whose shifter lobes are worn bad is not a good idea! Best to replace the gear also.

The following was taken out of my database and may be of some interest to you.

(Jumping Out Of Gear - Manual Type)
(J. Reeves)

This pertains to lower units on all OMC manual shift outboard engines, or any OMC engine with lower units defined as a Shift Assist or a Hydro Electric Shift unit which incorporates a "Shifter Clutch Dog".

Within the lower unit, splined to the prop shaft is what is most often referred to as a clutch dog, hereafter simply called dog. The dog has at least two lobes protruding from it on both ends, facing both forward and reverse gear. The forward and reverse gears also have lobes built into them near their center area. When the engine is running, in neutral, the gears are spinning constantly via the driveshaft being connected directly to the powerhead crankshaft, but the propeller does not turn due to the fact that the dog is centered between the two gears, and the dog lobes are not touching either of the gear lobes.

When the unit is put into either gear, shift linkages force the dog (and its lobes of course) to engage the lobes of the gear. The lobes of the spinning gear grab the lobes of the dog, and since the dog is splined to the prop shaft, the propeller turns.

The lobes of the dog and gears are precisely machined, most with right angled edges that could be installed in either direction, and some with angles slightly varied that must be installed in one direction only (one end only must face the propeller). Dogs that can be installed in one direction only, if reversed, even if the dog and both gears were new.... would jump out of gear almost immediately. Keep in mind that the lobes are precisely machined with sharp angles!

Due to improper adjustment or worn shift linkages, but usually due to improper slow shifting, those precisely machined sharp edges of the lobes become slightly rounded. Now, with those lobes rounded, as the rpms increase, the pressure of the gear lobes upon the dog lobes increases to a point whereas they are forced apart (jumping out of gear), and due (usually) to the shift cable keeping tension on the engines shift linkages..... the unit is forced back into gear giving one the sensation that the engine has hit something, and the cycle continues.

Some boaters with manual shift engines have the mistaken belief that shifting slowly is taking it easy on all of the shifting components..... Wrong! Shifting slowly allows those precisely machined sharp edges of the dog and gears to click, clank, bang, slam against each other many times before they are finally forced into alignment with each other..... and this is what rounds those edges off! The proper way to shift is to snap the unit into gear as quickly as possible.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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Wow That answers my question and then some There was no lettering that I could see, but there was a groove. Gues Ill be talking to you on Ebay. Thanks for the help. Much appreciated

Carry the dog/gear and propshaft to a GOOD machine shop and have them recut it. I have a guy that does my for about the price of a new dog($100)