JetRanger drive shaft boot
 

A friend of mine with a JetRanger III has been forced to replace the drive shaft boot three times in a matter of months – less than 10 hours of operation.

Grease was being sprayed around and the tele temps were black.

Does anyone have any suggestions on why this could be happening? Normally the boot lasts for many years

If the engine has been out recently? I have experienced this once after an engine change it ended up being an alignment issue.

Contaminated grease?

Not sure if my first reply worked so I’ll try again. I’ve had this problem before. We had the engine out for maintenance when it went back in it blew a boot in 3 hours tuned out to be an engine alignment issue. If there hasn’t been any major maintenance done it might be worth checking if something has moved.

I had one let go some years ago up at Surface Parasite.

Maybe the drive shaft is slightly misaligned? That would make the joints work really hard when under load, get hot and perhaps rupture the boot. But I am not an engineer. Does Russell at Camo's have a theory?

Perhaps the isolation mount has gone soft.

Check W&B on the flights he's doing. if really out of whack, that wouldn't help.

A good solution

https://www.kaman.com/sites/default/files/206B.pdf

A friend of mine with a JetRanger III has been forced to replace the drive shaft boot three times in a matter of months – less than 10 hours of operation.

Get a new maintenance provider.

As shown above, the Kaflex shaft fixes the problem.

You'd want to fix the alignment problem before changing to the Kaflex, surely? Something is abundantly wrong if the coupling is throwing 205 grease after only 10 hours.

Mount
 

If the engine mount shims were not disturbed, it’s the isolation mount...

Engine side? Have them check to insure the firewall driveshaft covers and cones are installed properly. In some cases if installed 180 out will cut boot on engine side. Temp Indicator go black because of loss of grease. As to alignment or iso mount bad, if they were that bad these same firewall covers/cones would be wiped out first and probably the shear plate for the "donkey d..." as well mounted to the bottom of the xsmn.

https://cimg2.ibsrv.net/gimg/pprune....29d1ff72dd.jpg