1973-74 40hp evinrude driveshaft removal

[1506cmo18]

Re: 1973-74 40hp evinrude driveshaft removal

I know it sounds like I am making it harder however, the first drive shaft I received was too short but yet it was for the motor. So I had a machine shop extend it to 28". This weekend I thought it would work but the driveshaft keeps dropping out of the top end. AND i have everything in place except the key way. So will the key way make the difference and hold the shaft in the head?

 

[tx1961whaler]

Re: 1973-74 40hp evinrude driveshaft removal

The lower unit holds the drive shaft in place when it is bolted into the midsection. An assembled lower unit looks like this, with the driveshaft in the gearcase, the water pump impeller, key, and housing in place. Then this whole thing gets bolted to the midsection as one unit. The driveshaft is never just hanging out of the motor by itself.

 

[1506cmo18]

Re: 1973-74 40hp evinrude driveshaft removal

Yes fair enough, explain this then...

when the motor is up side down everything works, goes into gear great and will turn over the motor.

As soon as I turn it up right, it no longer grabs onto the crankcase.

So will this keyway solve that??

 

[tx1961whaler]

Re: 1973-74 40hp evinrude driveshaft removal

Yes fair enough, explain this then...

when the motor is up side down everything works, goes into gear great and will turn over the motor.

As soon as I turn it up right, it no longer grabs onto the crankcase.

So will this keyway solve that??

No, but actually having the correct length driveshaft installed in the pinon gear in the gearcase will help matters greatly. Is this a long shaft or short shaft motor??

 

[1506cmo18]

Re: 1973-74 40hp evinrude driveshaft removal

Short shaft...

I put the keyway in yesterday and it still did not fix my problem. So either the shaft is still too short or the crank splines are stripped

is there anywheres I can get some specs on internal parts of the motor? I.E the proper length of the shaft

 

[1506cmo18]

Re: 1973-74 40hp evinrude driveshaft removal

I ended up welding inside the pinion gear to get the shaft to stay in the motor. It would only drop about a 1/4 inch out of the motor, so I filled the pinion gear in with weld.

Too keep the impeller spinning on the driveshaft I added a foam gasket underneath the impeller to lift it up on the key way.

Test run tomorrow