Prop size???

I have a prop with no markings on it other than pr242 made by michigan wheel, it is on a 275 outdrive,non through exhaust. Does anyone know what size this would be, i've googled the numbers and came up with nothing, thanks.

Also for got, going to order a new prop, but how do you determine if you have a long hub or short? I know it would be some type of measurement i would assume

It's a 14 3/8" x 19" pitch. I believe it's left hand and short/standard hub - Please doublecheck!

here's one on ebay

http://cgi.ebay.com/ebaymotors/MICH...3830143QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear

I would consider switching over to a Solas Amita. About $100 delivered from iboats.

If you sit the prop on the bench and drop a tape measure down through the center - and the the length of the bench to top of hub ~4" you have a short or standard hub. If it's 4.5" its a long hub.

Thanks, that explains the problem, the pitch is to much.it is a right hand, and was a short hub. I need a 15x15,i'm running a 19ft 2200lb. Cuddy. Just ordered the solas from iboats $97.95 and free shipping. Had to get the long hub, the only short hub they have is oem from volvo for $272.00 which is outragious for an aluminum prop.so will just remove the spacer between the cone and prop.

Which engine do you have and what was your wide open throttle rpm?

I've got the bb140, 125 hp. My wot is about 4000 to 4100 rpm

re: "so will just remove the spacer between the cone and prop."

While the standard parts call outs for Volvo short hubs show two different configurations,

(see bottom of page 1 of )

http://www.go2marine.com/docs/mfr/michiganwheel/volvo_yamaha_stearndrive_props.pdf

I have only ever seen a third, different configuration on 200-270 drives ( and by no means do I infer that my sample size was large!).
The difference is that the cone has the castlellations on the inside face that the locking washer uses and no "spacer" with castlellations. If you do have a separate "spacer" with castlellations and you remove it, you will have no way to secure (lock) the cone to the shaft (unless you happen to have a drive with a tapped hole in the end of the prop shaft). I suspect that "El" and "Rick" will have further words on this...

Yes, i have the hole in the end of the prop shaft for the allen bolt, was going to tighten down the cone and allen bolt also adding some blue locktite to the allen bolt threads.

I'd use blue on the cone, as well.

I wouldn't be surprised to see you pick up 1,000 rpm if you get that motor into its peak HP range.

What is your motors recommended WOT range?

Volvo manualcalls wot for my engine 5500 rpm. And cruising speed at 5000 rpm.i've come to accept the fact that 5500 rpm. With this engine on a 2200 lb boat just is'nt possible. But i've gotta do better than 4000 rpm. I'm getting 30mph. On gps now at 4000 rpm. So hopefully with the different prop it won't take so long to plane, i know 35. Mph on this boat is about the max your gonna get out of it with any prop.

yes,prop was the problem,got the 15x15 solas long hub, it does fit on the short prop shaft with out the spacer and has'nt budged, the way they make the prop when you tighten the cone it compresses the rubber a bit in the middle of the prop which acts something like a lock washer, also blue locktite on the cone threads and the end allen bolt. boat still gets right around 30 mph. but wot is now around 5100-5200 rpm. and planes with almost no effort even pulling an inflatable.

That's great and good of you to circle back with your results - which will help others.

If you're looking to dial in a tad more top speed, check which hole the tilt pin is in.
With the over-sized previous Prop there's a good chance it's in the lowest position(closest to transom).

If it is, working your way out further may yield some very positive top speed results while maintaining the good aspects you like now.

Lowest position will yield quick planing, but somewhat bury the nose at top speed (read, speed robbing drag).

The highest position will take a little longer to plane with more bow lift, but at high speeds will eliminate a lot of nose drag and can often add 3-4+ mph.

You may find a happy medium somewhere in between.

The Amita has the quick plane great stern-lift of the 4 blade AND pretty high raked blades for bow lifting when trimmed out which may yield some great top end #'s.

My boat with power trim, runs 43mph Wot at lowest trim and 50mph trimmed up.