An otherwise excellent 26-7 transmission has these cracks in 4 of the 6 bolt holes. Do you consider it worth using?



Allan from down under.

A bit of loctite Allan, and you or I wouldn't live long enough to see it fail!

Just a word of warning. The first T I got had a similar problem. One of the bolts came out! Yes it was wired but it still came out! It destroyed the starter ring and the magneto and then landed on top of the oil screen top of the transmission. That makes a big bang. So If it were mine, I would try to find a better drum.
Norm

Just a word of warning. I had one of those bolts come out of the first T I bought! Yes it was wired, but it still came out! It makes a big bang when that happens. It took out the starter ring and the magneto and then landed on the oil screen on top of the transmission.

If it were mine, I would look for a better drum.
Norm

I don't know why that happens. I posted this and then I looked at the bottom of the thread for it and it was not there so I thought I must have pushed the wrong button and posted it again and now it is posted twice!
Norm

I would "stop drill" the cracks with a 1/8" hole just past where the crack appears to end. Any reduction in strength will more than be offset by eliminating the "stress riser" and reducing the risk of crack propagation. Then I would tighten carefully to about 25 ft lbs torque and safety wire

Most of them we see are cracked and I have never seen a catastrophic failure of one in this area.

Thanks Les,
I will keep the drum in reserve and do your drilling trick. I have a sound one I can offer my customer, or he can choose to run with his and your suggested safety mod. With dry holes and Frank's Loktite, it should be OK.

Allan from down under.