I am working on the ramp 7 flight hours from my hanger/shop. Have an irritating oil leak from my front seal (350i) and am scheming to replace the seal. Have a new seal on hand and have down time due to weather. The biggest challenge appears to be finding a simple method to lock crank to allow removal/install of prop flange bolt. Specs call for torque value of 300Nm. That’s 221 ft pounds.  And yes, I am too cheap to buy the special tool from Wick’s for a one time use. Ray discouraged me from using rope stuffed in cylinder. Other ideas? Any pitfalls that others have experienced in replacing this seal? 



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Ralph, IMHO I think it is worth owning a tool of some sort for holding the prop flange while setting or breaking torque on the prop flange bolt.  You'll be needing to use it more than once in this case to do the 5 and 15 hr torque checks on the flange bolt after you do the seal replacement.  I fabricated one from square tubing and plate metal I had on hand.   I suspect Robert Helms or Ray would mail/loan you the tool for the job.  For me, the hardest part was removing the thrust bearing mount due to the fit and sealant...nothing to grab on to and pull.  Uniform continous light tapping around the mount with deadblow hammer until I could wedge a thin shim between the engine case and the mount to "wedge"  and wiggle it off did the trick for me.  The seal goes in relatively easy, then it's just a matter of cleanig up the old sealant (PITA) and putting it back together.  Be aware that you most likely will need to tap and drill the prop flange bolt locking collar (part E022510) for the grub screw after you torque the prop flange bolt.  The alignment of holes (prop flange and locking collar) to insert the grub screw will likely be off.  Overall the UL Power interactive maintenance manual gives a good description for doing the seal replacement and associated work.   Best of luck!



Thanks for the input. Reviewed the online info, thought about it, and rehung my prop on the plane. Just too many things to go wrong for this to be a ramp project. An irritating oil oil leak can wait until I return to my my hanger. I will install a new R/R and hopefully go fly while the sun shines!


Sounds like a good plan.  Nice to have access to familar workshop and tools when working on your plane.


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