prop and lower unit question for 175 hp Johnson

Joined
Nov 18, 2008
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11
hi guys
I'm back to ask a few questions....we had to replace our lower end on our 175 hp Johnson due to a collision with the rocks down here in Mexico... the new used lower end has a 17 pitch prop compared to a 19 on the old one... could anyone tell me the differences in performance between the two props... which prop would be more fuel efficient trolling between 7 to 8 MPH? also the new unit looked to be in better shape than the old one... but when we went out for test run... i hear a high pitched whine that was not there before... we ran it for 3 hours and the whine did seem to get better as we went along....could this whine be because the unit is tighter than the old one or do you think we are heading for disaster again?:eek:
thanks again for your help ..oldgringo
 

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tashasdaddy

Honorary Moderator Emeritus
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Re: prop and lower unit question for 175 hp Johnson

change gear oil, check what is in it. the prop depends on what you max RPMS are at wot.
 
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