Autoprop Bearing Replacement

Mike Ondra

Haven't seen many postings on Autoprop bearing replacement. We are in process now. The kit from AB Marine in Rhode Island was $750 for the bearings and races, a bit salty. The blades had a bit a wobble after several thousand hours of use, hence the decision to replace the bearings.

Following the instructions, the prop came apart quite easily until the last step, removal of the inner lower track, the stainless bearing race inset into the hub. No holes from the back to punch it out, no surfaces to pry against. The instructions mentions several versions of the hub but no clues as to how to extract, other than to contact Autoprop dealer for further instructions.

Their suggestion to superglue stuff to the stainless race seemed dubious. Second suggestion was to drill through the stainless and slightly into the brass of the hub and thread the stainless to receive a bolt. The bolt would be turned into the stainless, push against the brass and pop the race. This was tried and succeeded only in stripping the perhaps too small bolt. A larger bolt may have worked as it would have caulk the thicker portion of the race and provided more thread surface.

Ultimately we drilled and tapped all the way through the hub. Then turned a bolt through the brass from the inside just short of the stainless. Then a bolt through the stainless snug to the bolt in the brass. Then turned the bolt in the brass until the race popped out. All three came out fairly easily with this approach.

We now begin the reassembly.

Note: The installation instructions provide a procedure for simply adjusting/tightening the bearings should they be loose and cause vibration or wobble. This would be the proper fix to try before spending the time and money for a full bearing replacement. Scanned bearing adjustment instructions posted with photos.

Photos under Aletes SM#240


Join to automatically receive all group messages.