Need Prop advice - Newbie

[mcleaves]

I have a 1984 Bayliner Cierra, 21 ft with an AQ125 4 cyl Volvo and a 280 outdrive. I spent the past year overhauling the engine and she runs like a charm. gave her a water test for the first time (NEVER BUY A BOAT WITHOUT A WATER TEST - LESSON LEARNED!!!) this weekend and it went well. The prop is beat to hell will the end of the blades actually folded over in places. I clearly need a new prop before I do much more boating. With this engine and such a heavy boat I could use some help getting her up on plane too. How the hell do I find the right prop for this. There are so many dang choices and I can’t figure out which ones even fit my outdrive! I could use some hand holding on this one.<br /><br />Thanks in advance

 

[roscoe]

Re: Need Prop advice - Newbie

http://www.boat-props.com/propellers/s/Volvo_Penta/Outdrives/R <br /><br />For tech help or ordering, note the 800 phone number just above the listing on the left.<br /><br />It will help to know the diameter and pitch of the prop you are now using. These numbers should be stamped on the prop, somewhere.<br /><br />Glad you got the old girl up and running.<br />At least now you know it is in great shape.

 

[mcleaves]

Re: Need Prop advice - Newbie

Thanks Roscoe. It was a lot of work, and had I paid a marine mechanic it would have been cost prohibitive. But, in the end, with about 800.00 in parts she runs great. It has been a great learning experience on marine engines, and was actaulyl all worth it. I feel very comfortable working on these things now. Outdrives, well, that the next step I guess..<br /><br />That said, The only numbers on the prop are B66975. I looked everywhere previously for diameter/pitch indicators. nothing. The prop is either too beat up, or simply not stamped. I measured the length of one blade to the outside edge of the prop cone housing (approx 5.5 inches), and then measure the diameter of the prop cone housing (3.75 inches). If I do the math right and add in the fact that the blades are shortened a bit by abuse, it comes up to 15 inches. There is probably three inches to spare between the stabilizer fin and the top of the prop.<br /><br />Any idea what kind of pitch I could be looking for or will the prop guys really give advice on what I should buy?

 

[JB]

Re: Need Prop advice - Newbie

Moving to I/O

 

[andrewgroup]

Re: Need Prop advice - Newbie

A local Prop Shop here in Indianapolis is actually a division of the TurboProp Manufacturing business. The name of the shop is Precision Propeller<br /> http://www.turbo-props.com/Repair.htm <br /><br />The folks there have been the best resource I have found for my prop work. I've given them the barest of numbers and they have determined exaxtly what I had.<br /><br />But your problem is getting up on plane...<br /><br />starting with what you already know about how the boat planes out assume several things.<br /><br />Having that prop properly repaired, aligned and cupped will do wonders.. If you plan to do more tubing, skiing with your kids rather than a lot of WOT cruising I would suggest having them repitch the prop 1" to Start...Here was my experience...<br />18' bowrider, 4.3ltr V6 OMC cobra 14 x 19 3 blade aluminum prop...at 4600 RPM I was getting about 45.5 Mph and the bowrise and dolphing was pronounce...<br /><br />repitched to 18", added a stingray whale tale and 4600 rpm nets about 41.5 Mph, but hole shot improved greatly, dolphining is gone, stears like a waverunner and it scares my kids to be tubbing because I can put them anywhere I choose....<br /><br />Your Mileage may vary...<br /><br />Andy

 

[merc 140 pontoon]

Re: Need Prop advice - Newbie

It's for Mercruiser, but it still may help you: http://www.mercurymarine.com/prop_selector