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Capt Pat,
Know we discussed prop size recently but I can't get the 'Search' to find the posts.
Help.
THanks
Mikey

6BTA 300hp, zf220s trans 1.5:1 trans, 1.5" shafts, 4 blade 20x23 lite cup nibral props. 3000rpm WOT with full load.

--JK

I have a new pair of 4 blade 20 by 23 but they have a 1 3/4 bore. Might use a nylon reducer bushing. Let me know if you need them

713-906-0842

John, Don't know nothin' bout no nylon bushing. Let's ask the Faithful. What say you all? Is this a permanent kind of thing or is there another way or do I tell Mr. Cranston to hawk his wares elsewhere?
Sure could use a set of props to get off the hard and test the systems. Probably won't happen until Spring, but . . .

No bushings, gotta lap the bore to the shafts with valve grinding compound to get them vibration free. You got your prop answer above....shoot for 2950-3000 with your 6BTA 300 CPL 970s. Go with JK.

UV

Hey Mikey,

I wasn't trying to sell you the props. If they would have worked for you, I was going to just give them to you.

I'd pass on the nylon reducers for anything but an emergency, unless your a blowboater or running low hp, not our case.

However, they make bronze reducers that work fine.
The downside of reducers is they require an extra step to install and require a non standard key, not a big deal unless it gets lost. Then you have to buy from company or have made, not a major expense either way, just a pain. I'd keep a spare, actually I do as my props are installed with reducers, run better then the new wheels I bought, so I keep my new wheels as spares.

Bushings can also be welded in so you don't have to mess with them, in my opinion it's not worth it on these small diameter wheels.

A reducer lists 110.00 going from 1.75 to 1.5 on my old price sheet.

I used nylon bushings on 28Topaz for years at 27knots with no problem ever. For a generous free set of wheels absolutly i would run them. With bronze inserts and an extra keyway or two you will be set up. Beats the heck out of paying 2k for a set of the same wheels. 4 blades are smooth anyway and mine on the Volvos spun 3600wot with NO vibration and nylon at that. Troy

John,
Bless you my son. Just wanted to be sure. Didn't realize they were a gift. You da man. Appears I should shy away from inserts with that much HP and torque.

Anyone else have what JK says? 4 blade 20x23 lite cup nibral props

The nylon bushings do work well, I sell a bunch of them with little issue.

But, I sell more bronze bushings with zero issue... so for the few extra bucks I recommend bronze.

I have run nylon bushing before without any issues at all. I picked them up from my prop guy, claims he sells a bunch of them and has never had a complaint and/or problem that was related to the bushings. I ask a bunch of questions before using them!

If one of the faithful donated a set of props that needed bushings to fit my shafts....I'd be on my way to the prop shop to get some bushings.

If the bushings make you nervous the prop shop could add some bronze inserts in the wheels, then you could lap as UV suggested.

John, You have raised the bar considerably for project donations.

Mikey,

I got the 6BTA 300hp, zf220s trans 1.5:1 trans, 1.5" shafts, 3 blade 21x23 medium cup nibral props. 3000rpm, 32 knots wide open.

Vince Luciani

John,
Enjoyed our conversation. Always good talking with another guy deep in the restoration process. Whew! With all the pix of boats being finished it sure has reinvigorated me and my efforts.
Since the consensus is that these props will work I will take them.
Send to: 5160 Irvington Road, Irvington, Virginia 22480.
Phone 804-438-5543.
I will check with the local prop shop to get this done right.
Meanwhile, I will find the source of the Yanmar engine installation template.
Keep you posted.
Again, a million thanks, as Scot noted, you have raised the bar.

That is generous!! Heck Mikey, for the price I'm glad to see that you are going to try them and see how they work for you! At least they will get you in the ball park without going deeply out of pocket. Trial and error prop purchasing can get expensive!!

See Mikey, all your buddies think I'm a swell guy. I'll mail them on Monday.

JohnCranston wrote:See Mikey, all your buddies think I'm a swell guy. I'll mail them on Monday.

John,

You are a swell guy, but don't let it swell your head.

Harv,

Too late.

He's right about that.

It was not too long ago that Capt. Pat. answered the same question with the following " No plastic on running gear " I agree.