MacGregorSailors.com

Well, after a long 5 months I was finally able to get the Solas prop back to the shop in Ventura. Yep, it's junk. The hub has spun, and it just isn't feasible to try to fix it. I sure spent a lot of dough on something that only worked well for one outing. Brian at Valley Propellers said that I wasted my money, and that for what I spent he could have modified a really nice stainless prop for me. I had torqued it down right and didn't hit anything, but he said that it just isn't made well enough to push something as heavy as a Mac. So Robert if you read this you are one lucky SOB that your prop is still working for you!

The only good news is that Brian was able to lightly cup my Michigan 3 x 12 x 10 prop at the same and now it's great, with full tanks, empty ballast, and two crew I can do 16.5 knots (19 mpg) in calm seas, at 6,400 rpm.

I'm going to keep the Solas - to use for target practice.

OK it's my turn to jump in with both feet! I have a 2005 F60 Yamaha 4 stroke outboard motor. And I'm hoping someone here also has one because I need advice in the propeller choice. I bought it with a propeller that was just a guess to start with and I was supposed to let them know if it was the right right prop. I didn't even have a tachometer.

How the heck was I supposed to know if it was right or not?!?!??

OK so now I have a tach and I know a few more things. First, maybe I should have gotten the high thrust version of the 60hp motor. But since I didn't, here's what I have:

Motor:
2005 F60 4 stroke
1.85 gear ratio
60hp @ 5500 rpm

Current Prop:
10-5/8" dia x12" pitch
4400 rpm and almost 16mph (by gps with empty ballast)
The trouble is it wouldn't quite plane.

My best guess for a new prop:
12-1/4" dia x 9" pitch - Thanks to everyones experiences here.

This is partly based on availability. Here are the other available choices:

ALUMINUM 3 BLADE
12-1/4x9
11-3/8x12
11-3/8x11
10-5/8x12 (Current)
10-5/8x13
11-1/8x13 (F60)
10-1/4x14
11-1/4x14
10x15
11x15 (F60)
10-3/4x16
10-3/4x17

PERFORMANCE 3 BLADE
10-1/2x12
10-1/2x13
10-1/2x14
10-1/2x15

BLACK STEEL
12X11
11-3/4X12
11-1/2X13
10-1/4X14
10-1/4X15
10-1/4X16

I'm hoping this will work perfectly because I don't know which prop to try next! I'll post my results soon.
Chris

FWIW...
go with the largest diameter prop available for your motor. then try to go to the lowest (or one up) pitch. making sure that the prop blades are large with alot of surface area (as opposed to sleek and streamlined).
generally, a pontoon/work style prop is best.

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

There's a way
..
Tohastsu makes a 11.4 diameter 7.1 pitch 4 blade prop that would be ideal.
http://www.tohatsu.com/tech_info/prop.html
..
Ask them if it will fit, if not, ask if a Mercury rubber hub can be pressed into it to make it fit. Also the prop must fit well enough on the outside to direct the exhaust through the prop properly so bubbles don't interfere with the blades.
..
Also, with some searching you might be able to find a Mercury compatible 8 pitch prop.
..
The www.MercuryMarine.com web page has a calculator to select the proper pitch. Using that calculator and assuming a 3500 lb. pontoon boat with 500 lb. of people and 24 gallons of fuel a theoretical 7.7 pitch prop would give 15.7 GPS speed at 5750 motor RPMs using the 1:1.85 gear ratio. Note that the Tohatsu is 7.1 pitch with 4 blades, I think the 7.1 four blade prop would be about equal to a theoretical 7.7 3 blade prop, because the 4 blade prop will have a better grip and slip less.

Robert

Can you point me in the right direction to find that calculator?

Not having any luck.

Thanks

G

beene wrote:Robert

Can you point me in the right direction to find that calculator?

Not having any luck.

Thanks

G

Try here, G.

Thanks a MILLION KM

Just what I thought.

14x13 for best overall and top speed.
14x11 for best hole shot.

I bought both of those thinking that would be the case.

Can't wait to test them out.

You're the best!!

G

Had the M out today in the James river for prop testing. I swapped out the standard Suzuki 13 pith for a Michigan 3x11-3/4x10. I had a major cavitation problem with this prop and could only manage 9 Knots. ABove 4500 rpm I had cavitaion.

I noted there was about 1/2" distance between the gearcase housing and the prop housing. I think this is too much, and as a result I was pulling air in creating the cavitation. I read earlier posts about a need to replace the thrust washer.

Should the prop housing overlap the gear housing slightly (so you do not see the shaft)? Will contact Michigan tomorrow. BTW my OB is the Suzuki 50 hp.

JJ wrote: ... Should the prop housing overlap the gear housing slightly (so you do not see the shaft)? Will contact Michigan tomorrow. BTW my OB is the Suzuki 50 hp.

JJ ... you need to read this other thread, my friend:

Michigan Wheel Prop Problem on Suzuki DF50



Sailors,
the Search button is your friend. In this particular case the search words couldn't be any more precise.
I'm guessing that JJ's prop is a non-starter. Too bad he didn't find that thread earlier.

Thanks Frank. Exactly my problem!

It's interesting that MW advertising says "replaces your old prop" and yet it doesn't. I had assumed when I bought the prop that I would simply replace the Suzuki prop. Hmmmm...didn't think to search further as I thought this thread was pretty thorough.

Thanks again.

Examine the complete prop replacement kit, it might be that the new prop needs a different thrust washer to allow it match up with the opening to seal away exhaust properly.
..
If MI Wheel props are having difficulty fitting with Suzuki outboards, bring that to their attention and they should take steps immediately to measure and machine one for you and thank you for your input.

Robert,

You need to read that other thread, too.
Seems that Moe has gone round 'n round w/ Michigan, to no avail!

OK, I took another look at my Michigan prop (3x12x10) as it was not fitting on my Suzuki DF-50 properly as explained above.

Upon further examination, I found that there was a spacer on the shaft which could be removed (this was in addittion to the thrust washer). I removed it, replaced the prop and it fit beautifully into the socket of the gear hub!! Put the spacer behind the prop on the spline shaft, replaced the locking nut and everything looks good!!

See pictures below:

http://i163.photobucket.com/albums/t285 ... efore1.jpg

http://i163.photobucket.com/albums/t285 ... efore2.jpg

http://i163.photobucket.com/albums/t285 ... WAfter.jpg

I plan to test out the prop this weekend, and I will let everyone know how it performs.

In the end, I got another thrust washer from MW that set the prop in a LITTLE deeper. From looking at JJ's picture of the prop to gearcase space and the exposed threads behind the prop nut, it looks like they improved it yet again. I guess I was their beta-tester.

JJ, that should work. I never got to test the replacement they sent me, but Don Fitzgerald tells me it's working fine, and it wasn't in the gearcase as far as yours is. Note the Suzuki prop recesses in much further than either.

--
Moe

Has anyone used a Michigan Wheel 4-blade on a Mac? Valley Propellers wants to sell me a 11.5 x 9 x 4, for about $100. I'm going up there next weekend to sail out to Anacapa Island, so I might as well buy it as my early Father's Day present. I have to go by there anyway to pick up my junk Solas, so I can put rifle bullets thru it. Bet it just shatters.