TC (40) installation issues

[Millwright]

So I got an "off brand" 40 series TC, and a Honda clone "Power Fist" engine.
Couple of issues.....

On the TC, the driver pulley has a 1" bore with an integral key machined into it. The Key seams to be undersized as there is a lot of play when it is slid onto the engine shaft. I'd say several degrees of rotation, plus the key is not tall enough. I'm sure that under load, the key would just fold over.
The keyway ( 1/4" ) on the engine shaft is correct, I checked it with other keyed components.
The problem with the engine, is that the shaft is too short by 1".

So I plan on welding on a shaft extension, and then bolting the TC on, and then putting a small weld to lock the TC to the shaft so it can't spin and overload the loose key fit.

Any other suggestions?

 

[madprofessor]

That welded/forged/whatever keystock is a factory defect. Nothing on the planet would fit that correctly, and a replacement might be the same deal. Just order a TC that fits, cough up the money for something with a satisfaction guarantee with free return shipping.
No weld anyone could do to lengthen that shaft would ever be as strong as a solid shaft, and it needs to be. Nice bevel there for a surface weld, but you have to grind most of it off to smooth out the shaft. Don't do it, get something that fits.

 

[karl]

Thought about cutting a strip of shim stock to take up the slack?
Could even be bent 90 degrees , so one side sits under the key , to make it
more rigid/ easier to install.

As long as the weld penetrates deep, grinding off the extra material at the surface is no biggie.
Plus the bolt in the end of the crank helps thing along.
Might need to replace the crank seal by the time it's said and done.

 

[Millwright]

Well I went ahead and welded it. Used TIG, and was carefull about heat input. I think it will do. It's pretty much just acting as a spacer, as the crappy key doesn't engage the new section at all.

That welded/forged/whatever keystock is a factory defect. Nothing on the planet would fit that correctly, and a replacement might be the same deal. Just order a TC that fits, cough up the money for something with a satisfaction guarantee with free return shipping.
No weld anyone could do to lengthen that shaft would ever be as strong as a solid shaft, and it needs to be. Nice bevel there for a surface weld, but you have to grind most of it off to smooth out the shaft. Don't do it, get something that fits.

Lol. I went for it !
Worst case scenario, I grind it off and buy a comet.

 

[madprofessor]

Wow. Look at the nads on this guy! I do appreciate going for the gusto, so my hats off to the effort.
One thing worries me, what karl said about the crank seal. Don't know what you did about being "careful about heat input", but I do know nothing protects seals or bearings or etc. better than removing them before banging or heating.
Can't imagine how you kept the shaft seal surface cool to the touch, which the seal would appreciate.

 

[Millwright]

@madPro,
I figured the 1" shaft is a pretty good heat sink. It absorbs a lot of heat rather than allowing it to transfer too quickly. The TIG process is nice because it keeps the heat zone small with a centralized weld pool.
A cold wet rag on hand to drape over the shaft at the seal worked too.

 

[madprofessor]

I really need to expand my knowledge. Bought a Klutch ST80i stick/ TIG welder originally, but not the TIG package. That $100 package doesn't include an argon bottle, first argon fill, pressure regulator, flowmeter, or fill rods. If I'd just get off the wallet I could learn how to TIG and know more about how it goes.