What temp to heat my steel wheel gear!!

[hessel]

While tearing down my engine, it became apparent that I needed to replace the steel wheel gears on the intermediate shaft. They where very worn and actually 2 teeth where missing...

In wayne's book he explains how to put the Crank gear back on the crankshaft by heating them up in oil to let the metal expand before refitting. He also mentioned specific temperatures for each gear.

To what temperature do I heat the steel wheels before fitting them on the int. shaft?

Thanks for your help.

[David]

The coefficent of thermal expansion of steel is about 6.3 x 10^-6 per degree F. So if the diameter is 3/4" the expansion at 300F would be 6.3 x 10^-6 x 3/4" x 300 = 0.0014". I don't know the diameter of the shaft or the fit, but you could calculate how much you need to heat it to have a 0.001 to 0.002 clearance when you slide on the gear. I wouldn't heat it over 500F for fear of softening the material.

[john walker's workshop]

a press is generally used for those. on and off.

[Tim Walsh]

If you're quick then you can just heat them up in a bath of oil and drop them right on. I replaced mine, and one went on nicely, the other had to be pressed on.

[Eagledriver]

I heated mine in the oven to 300 degrees and put the shaft in the freezer. I pounded the gear on with a big socket and a hammer. It went on with no problem. If it gets stuck you can always take it to Napa and have it pressed on.

-Andy

[Fishcop]

I used a friend's press to get them off and Eagle's method to get them on...