merc 100 prop selection

[12volts]

I would Like to purchase a new prop for my boat and I think the one that is on there is the wrong one. I have a 1965 Merc. 100 with a wot of 5200rpm it is on a 1967 MFG deep "V", 19ft fiberglass boat. The weight of this boat is unknown at this time my carry weight with equipment and people is around 5-600 lbs. This boat is used exclusively for fishing and currently the top speed is only 20 MPH according to GPS. Can this speed be right? it also is about the same on my speed sensor. I am looking for a new aluminum prop but am perplexed over all the variables. For someone who knows props What would be the best prop dia./pitch for this boat. Currently there is a 13x18 on there now and if I am reading my manual correctly it should have a 14x15. I have enough clearance for a 14 or the 13 3/4. Could someone shed some light on the proper prop?<br /><br />thanks in advance<br />Russ

 

[ronmold]

Re: merc 100 prop selection

Should be able to do 35+ w/ that old inline 6. I'm wondering why at 5200 r's your only getting 20. I had a prop that was repaired so many times it lost an inch of diameter - lots of revs but no go. Or more than likely your rubber hub is slipping. Check it and have the hub replaced if needed. 19 pitch should be an all-around good prop and a 17 will give you better performance with a heavy load, just don't over-rev when light. Try to find stainless if you can.

 

[12volts]

Re: merc 100 prop selection

Thanks...I will check for this Rubber hub on the prop, I havent pulled the prop yet. I think this is a "heavy" boat and will probably try a lower pitch, thanks for the info