PROPSHAFT FINISHED

The new propshaft is finished now. I had to have the shaft straightened as it cam in with a bow; was replaced but the new one was bowed too. Anyway the clutch splines are cut as well s the keyways and the snap ring groove to contain the bearing. 

 

The support bearing is 7/8" x 2" and the torque tube is 2.375 ID nominal so a sleeve is required.

The gearbox input shaft or constant mesh gear leaks down the keyways and drips into the torque tube. That oil can pass forward and end up in the clutch disk. See my previous post to prevent this. It didn't work. I have been advised to get a short length of bicycle inner tube to fit the gearbox input and to make a sleeve to Loctite onto the prop shaft to accept the forward end of the rubber tube. This looks like a great solution.

This photo shows the torque tube flange to the right with the propshaft sticking out to the left. The gear box is removed. When installing the gearbox I have the rubber sleeve rolled over on the  input shaft. I slid the propshaft into the input shaft and rolled the rubber sleeve over onto the alum. piece to make the seal.

I will follow up with how this works out.

 

new propshaft

 When driving I got a vibration at about 45mph. It has to be the dreaded propshaft whip that is so common with the F type Morgan. My choice is to make a new shaft from 7/8" dia. 4340 steel. The bar should come in by the end of this week so today I made a test spline to be sure I could do it; never done one before. It came out just great, maybe a bit too tight so I'll add a couple thou. of slop in the real shaft.

The Bulletin has several articles on the subject. I'll add a support bearing part way up from the rear but not at mid point of the shaft. Some of the articles talk about using 2 or even 3 support bearings but I believe one is enough. One works fine with the twin car 2 piece shaft and it has worked with my JZR also. The idea is to break up the harmonic frequency of the shaft and raise the critical speed of the shaft.

More to come on this as it progresses.