thompsondockside.com

I made the following post on Marinengine.com, but only got one response.. I am interested in the perspective of some others, since I know there are a lot of us with 75 Johnson/evinrudes in the 1961 age range...

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I am interested in opinions on the risk of damage from starting my 1961 75HP Johnson in gear.

I put about 4 hours on the motor last year (restored Thompson, repainted & reworked motor), and realized that my periodic motor jerking was due to a worn clutch dog. I took the lower unit off, and we replaced the clutch dog, and cleaned up some minor damage to the edges where the ears contact the gears.

Although I will set the idle as slow as possible, and make sure I shift with a quick snap rather than slow movement of the shift lever (manual), I am wondering if it would be smarter to just start the engine in neutral, get things warmed up, shut it off, shift into gear, and then restart.

The literature says two things... 1) that it is OK to start in gear, but this should be limited to docking situations where a stall needs to be recovered from and 2) do not shift into gear when the engine is not running...

Any idea as to which risk is a better choice? I will be 5-6 weekend per year boater, and if it is low risk, I would rather eliminate any potential for wear as the dog engages

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Here is the response I received, which seemed to make sense.

Unless the dog clutch is exactly alligned , it will not go into gear. If you try to force it , you will probably damage the shift cable / mechanism. Never try to engage a gear without the engine running , or someone spinning the prop by hand . As for starting the engine in gear , do you not have an ignition cut out switch that prevents this ? ( or did this only come out on later models ?

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Any thoughts anyone... I know there is at least one retired OMC mechanic out there.

Thanks.

John, I also am running a 75hp Evinrude 1961 which has the mechanical shift as opposed to the latter (1962 ) electro-mechanical shift system. It sounds like you have researched the "situation" pretty well.
My opinion... if the clutch dogs are already warn I suspect that you will continue to expierence popping out of gear. I don't thing that the continuing action of CORRECTLY shifting will materially degradate the condition that already exists. The dog clutches on motors that has been treated properly should last forever. My motor has never been worked on and is 100%.
To your specific ?, I do not see any mechanical problem with starting in gear... may be some concern for the obvious "dock crashing/ passenger ejection" issues.
As for operating/maintaining these vintage motors... strongly suggest that one get hooked up w/ the local chapter of the Antique Outboard Club (aomci.org) that's where the expertiese resides ( not to mention inexpensive parts)
PS... check out your local metal salvage yard's aluminum pile , these bigger vintage motors show up regularly ... $4 / pound- that can be a pretty cheep parts source.
Joe Brincat

Clutch dogs can be reversed, which allows using the unused back edge. The gears are another problem, short of reginding, they must be replaced.

Great tips, fellas.. thanks..I guess I didn't state it very clearly, but when I replaced the clutch dog it was a new one... So I am hoping that the new one will give me a new lease on life. I am just trying to eliminate the situation from repeating.

The teeth on the gears were perfect, and the guy that helped me on this has squared up edges where the dogs engage before and claims that I should be OK. The conclusion is that the previous users had poor shifting habits, such as shifting at too high RPM, or slowly babying into gear rather than a snap.

I will find out next week, whether our efforts paid off...

Thanks again.

In a perfect world you should replace both forward gear and dog.

I was a Evinrude factory certified mechanic, back in high school in the late 60's, but that was a long time ago.