1975 115 Evinrude Flywheel installation tips?

[jammer777]

hey Evinruders!

I'm waiting on a new flywheel key that sheared on me, i dont think i had hte flywheel torqued enough, but wanted to pick your brains on installing this fairly large flywheel and its center nut on the driveshaft, mostly around the tightening the thing up, i don't have a torque based impact driver, so ill be doing it by hand, just wondering what you guys have done to brace the flywheel so it can be torqued down properly other than having one of my teenagers hold on to those nice sharp teeth haha

I dont want to shear another key off

and while im at it ( cant find my manual cause im an idiot) whats the torque rating for the bolt? i think its 105 lbs right?

 

[jbuote]

Hey there!
​I'm still really new to boating (1 year and 3 days into it.. ), but I'll give it a shot.. lol

​First off, you'll want to make sure your tapers have a good mating surface. If they're pitted or scratched, you'll want to use valve lapping compound to get a better mating surface.
​It's the tapers that hold it in place with proper torque applied to the flywheel nut. The key doesn't hold it there..

Next, make sure the key is installed correctly..
​Pretty sure on yours (like mine) the key flat should be parallel to the vertical centerline of the crankshaft.. NOT at the same angle as the tapers..
​(Could be wrong there though..)

​As for holding the flywheel in place, you can use a strap wrench, or a tool called a Flywheel Turner, or even a screwdriver between the starter and teeth of flywheel. (Never tried that one myself, but heard it suggested here.. Not sure I would.. lol)

​Having a torque wrench is paramount. Without one, you'll never get it right and will shear a key again, or over torque it..

My 1971 50hp has the flywheel nut torque spec at 100 - 105 ft/lbs..
Guessing yours is the same, if not close... (you said 105.. lol)

​The experts here will correct anything I've gotten wrong in this..
​(An expert I am not.. Just recent newbie experience.. lol)

​For what it's worth, and hope it helps even if just a little...,

 

[F_R]

100-105 ft pounds is correct. I've used the screwdriver in the gears method on many, many motors without damage. But I suppose there is always a first time, so you are on your own concerning that. The tapers absolutely must be smooth, clean and dry. And you must use a torque wrench. Rent one if you have to. You can rent a flywheel turner while you are at it.

 

[jammer777]

awesome thanks for the replies guys! i thihk what ill do it is bolts from the puller, put a prybar between them and go buy a new torque wrench! haha what size is the bolt again? is it 32mm?

 

[jbuote]

Pretty sure it's 1-5/16" (or 34mm)

 

[interalian]

Pretty sure it's 1-5/16" (or 34mm)

Yes.

But don't put a prybar in among the puller bolts. I clamped a vicegrip on the lifting eye and had a helper brace the flywheel with a screwdriver while I torqued the nut. As for putting a screwdriver in between the starter pinion and the flywheel, it would probably work too, but I'd worry about bending the motor shaft.

 

[jbuote]

I just remembered one other suggestion I've seen here to hold the flywheel.
​Some have said they used a length of rope in the cylinder through the spark plug hole to prevent the engine from turning while removing and installing the flywheel nut.
​Again, haven't tried that one myself (I have a strap wrench) but it's another possible method to consider.. lol

 

[Bosunsmate]

yes ive used the rope method myself many times with good result

 

[jammer777]

awesome thanks for all the suggestions guys, im just waiting for this key to show up and ill get this thing on there and get the boat out on the lake to enjoy the summer! oh...wait...damn...summers over! heh