250 pro xs with silver lower unit. When i spin the prop by hand their is a grinding noise like prop is rubbing the housing. This is a new motor that has never been run it's on the showroom floor. Is this normal? It is not the ticking noise its more like a small grinding noise like the prop is rubing on something. I have done this with the reg black lower units and hear nothing but first time i have looked at the silver lower units and spun the prop by hand. They said its normal with that lower unit. Is this correct??
Torquemaster models do have a different sound while spinning the prop (slightly different bearing setup).
However, there should NOT be any sound that would indicate to you that the prop is contacting the housing.
If there is, I'd be looking for leaves, dirt, or debris between the gearcase and housing (behind the prop), or perhaps an incorrectly installed (or improperly torqued) propeller.
Dual Mercury Master Technician- for Mercury Outboards, Racing & Mercruiser Sterndrives in Greenville, SC. Still consider myself a "Marine Apprentice" after 37 years (learn something new every day).
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