Does anyone know how the coupling is fitted on the prop shaft? Interference fit or tapered? After installing a new PSS, I am at the point of slipping the coupling on the shaft. I have done this before successfully, but it was a replacement, not a new PSS install. I'm not sure if that shaft was wet sanded until the coupling went on. This install is replacing a stuffing box, so this coupling/shaft has never been touched. I don't want to take a hammer to the prop end and drive the coupling on due to potential damage to the tranny. Is there a safe way to get the coupling on? A press is out of the question, obviously. Has anyone had success with heat? If so, what was your method? Is wet sanding(400-600) and heat the way to go? May be some PB??? Can the tranny take some modest blows if cushioned with wood?
Engine is a Yanmar 3GM.
12/01/20 - My solution:
I honed the interior of coupling real shiny and cut a 2x4 to the length of the engine well(fore of engine drip pan to start of tranny flange). Lubed the shaft and coupling with teflon. Using the aft end of the 2x4 for leverage, I then placed a flat steel bar(90 degree to 2x4) against it's end. I was able to bang the coupling on without any contact with the tranny. The bar against the 2x4 absorbed the impact of banging the coupling on the shaft without any contact to the tran flange. I did use a block of wood on the prop end of the shaft when driving the coupling on. I hope this helps anyone else having trouble reinstalling a coupling on the shaft.
Engine is a Yanmar 3GM.
12/01/20 - My solution:
I honed the interior of coupling real shiny and cut a 2x4 to the length of the engine well(fore of engine drip pan to start of tranny flange). Lubed the shaft and coupling with teflon. Using the aft end of the 2x4 for leverage, I then placed a flat steel bar(90 degree to 2x4) against it's end. I was able to bang the coupling on without any contact with the tranny. The bar against the 2x4 absorbed the impact of banging the coupling on the shaft without any contact to the tran flange. I did use a block of wood on the prop end of the shaft when driving the coupling on. I hope this helps anyone else having trouble reinstalling a coupling on the shaft.
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