Propellor Identification

[geoffmck]

Could some one please help with explaining the details of the prop. on my 85hp Yamaha? Eg: diameter and pitch.

Stamped on the prop is:

48 77340 A40 13P

Thanks

[aussiebasser]

13P means 13" pitch. The other numbers seem to be part numbers. Maybe try a Yamaha dealer.

[FNQCairns]

Mate thats no good why do you have a 14 diameter prop on that girl - you towing barges:)

A 13.5x15 everyday alum Yam prop will suit you far far better if you are decent in the rev range ATM but you would be able to fine tune further again I am sure.

http://www.google.com.au/search?hl=en&q=%2248+77340+A40%22&btnG=Google+Search&meta=


cheers fnq

[geoffmck]

Thanks for that I had no luck with my searches.
I have only just bought the boat (16ft half cabin/Yamaha 85hp) and have only had time for one quick spin, just long enough to see that it will rev up near 6000 no worries which made me question the prop selection. I backed off pretty quickly because I want to get the motor serviced before I push it too hard.
I have downloaded the owners manual which specifies 4500 - 5500 max. rpm, so I will experiment a bit to try and achieve between 5300 - 5500. Any ideas on a starting diameter/pitch based on that info?

PS - The link you provided indicates it is a Quicksilver prop which I thought indicated mercury? Are the splines the same on Mercurcy/Yamaha, Eg: are props interchangable between the two motors?

Thanks

[FNQCairns]

If possible see if you can get 5500-5700 with a normal load, the prop I mentioned above would go close I suspect but ultimately it depends on how your hull is designed.

You have one of the Mercury flo-torq hub props with the Yamaha kit, this means you can use any mercury flow-torq prop, just slide the guts out of the one you have and insert into the new prop + you can use standard Yam props as well.

As a bit more of a gamble this prop may suit you also, dunno but if it did you would fly. I have the same engine 90hp and I cannot run the 16p below with a normal load.

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&rd=1&item=270220823486&ssPageName=STRK:MEWA:IT&ih=017

cheers fnq

[ausandy]

geoff, the part number you have supplied is a MERC prop part number. prop supplied as standard would have been a 17 inch alloy.