Dirty 30...prop that I cannot find

[cocacola]

My dad is restoring old outboards....a passion from his racing days in the 50's.

He's discovered the "Dirty 30" and made his own.

Now....he tells me he has no way to run it since he feels he cannot find a prop for it.

He says he needs a 9 1/2" dia x 15" pitch....don't know if that's right.

Does anyone know what prop he might need and where to get one?

He says he used to use OJ props in the day, but they cannot help us now.

fyi: if Ron Hill is still here....I bought Bunker's old boat, but sold it last Fall.

[DeanFHobart]

My dad is restoring old outboards....a passion from his racing days in the 50's.

He's discovered the "Dirty 30" and made his own.

Now....he tells me he has no way to run it since he feels he cannot find a prop for

He says he needs a 9 1/2" dia x 15" pitch....don't know if that's right.

Does anyone know what prop he might need and where to get one?

He says he used to use OJ props in the day, but they cannot help us now.

fyi: if Ron Hill is still here....I bought Bunker's old boat, but sold it last Fall.


Call Ron Hill... Look in the ‘red’ on top... Hill Marine.

[John Schubert T*A*R*T]

Pretty STIFF prop for a 30H, but if just a MK 30 might be OK

[cocacola]

Pretty STIFF prop for a 30H, but if just a MK 30 might be OK

Isn’t a dirty 30 a mark 55 on a Mark 30 lower?

[John Schubert T*A*R*T]

Isn’t a dirty 30 a mark 55 on a Mark 30 lower?
Never heard of that, BUT

[R Austin]

That’s a bigger prop than I ran on the 6 cylinder looper.
Don’t sound right for a 30H.

[racnbns]

My dad is restoring old outboards....a passion from his racing days in the 50's.

He's discovered the "Dirty 30" and made his own.

Now....he tells me he has no way to run it since he feels he cannot find a prop for it.

He says he needs a 9 1/2" dia x 15" pitch....don't know if that's right.

Does anyone know what prop he might need and where to get one?

He says he used to use OJ props in the day, but they cannot help us now.

fyi: if Ron Hill is still here....I bought Bunker's old boat, but sold it last Fall.

A picture of the motor would help. If your like me and don't do pic's describe the motor, no. of cylinders, mag. or bat. electronic ignition, type of gearcase and diameter of propshaft and gas or alky burner. Sounds interesting. Keep the info coming.

Bruce

[DeanFHobart]

Isn’t a dirty 30 a mark 55 on a Mark 30 lower?

Hello, as mentioned before... have you contacted Ron Hill at Hill Marine yet... he can help you.

[Tim Weber]

The only 30H that I can think of that might pull that would be a motor converted to C-service alky with a 14-21 gearfoot.

The Evinrude speedy twin service-C usually run about a 8 3/4" x 14 with the above gear ratio.

Tim

[Ron Hill]

Hello, as mentioned before... have you contacted Ron Hill at Hill Marine yet... he can help you.

We raced Stock Motors or serious modified alky burners. I have never heard of a Dirty 30. Tim Weber might be right, 20-H gears in a "C" foot...I know down Oklahoma way they did some strange stuff.

[Fastjeff57]

You guys got to be kidding! Lots of guys built these things and ran them for years--me, for example.

What's a Dirty Thirty and how do you build one? Take a 44 cube power head, put a Mark 30 crank in it (it fits and works fine), then mount it on a Mark 30 tower. The tiny impeller is up to the task--mine never overheated--but finding a prop with enough pitch is a problem. (The LU has a steep gear ratio--1.86:1 as I recall.) My buddy Dingy Bob scored a 17 pitch brass racing prop and fitted a 6 spline hub to her. That was the ticket for my 9 foot dink boat, and it ran great for years. I eventually went to a conventional Mark 55/ Merc 400 tower and LU simply because used props were easier to find.

Jeff