Rubber Hub or not?

[tarheelebbtide]

1992 350 Mag Merc w/ Alpha One outdrive....want to order a new prop and go up in pitch. There are options for props with or without a rubber hub...here's the stupid question....How do I know which I have? Does the prop have to be removed to see the rubber hub or should it be readily apparent just looking at the hub (I don't see any rubber at all when looking in the rear of the current prop and spinning)? Thanks for the help and apologize in advance for the ignorance.

 

[rndn]

Re: Rubber Hub or not?

If your prop is an older model it does not have a user replacable hub. If this is the case, then you need to purchase both the prop and a hub. If you have a newer prop you will need to remove it and look at the removable hub. You should be able to take the hub out by hand. If you have the newer style and want to save the money of buying another hub you will need to buy the same model from the same mfg.

 

[Dhadley]

Re: Rubber Hub or not?

There are prop campanies making props suitable for other hub kits. The most popular is what's called a square bore prop. It'll accept the Merc Flo Torq kit, the Turbo Guardian kit, Michigan Wheel has one and I think Solas too. I'm sure others make square bore hub props and kits too.

If your prop is a couple years old or more, most likely you have the old style pressed in rubber hub. You can still get them but eventually they'll become replaced by the user repalceable hub props.

 

[tarheelebbtide]

Re: Rubber Hub or not?

Here are some pics of the current prop....

http://s525.photobucket.com/albums/cc335/diamondheels02/Ebbtide/

 

[Dhadley]

Re: Rubber Hub or not?

Hard to tell which it is. The castle spacer is missing though. You'd have to pull it off to see which it is. Doesn't really matter though. You can use either. If it were me and I was going to buy a new prop anyway I'd get one with a square bore. That'll give you some options in the future.

 

[tarheelebbtide]

Re: Rubber Hub or not?

dhadley, how do i know if I'm getting one with a square bore...and what is the castle spacer....sorry for the ignorance here. Learning all of this for the first time!

 

[Dhadley]

Re: Rubber Hub or not?

When you buy a prop it'll say something like "hubbed for Merc" or "accepts Flo Torq hub".

As for the spacer there should be something there that those tabs bend into. It's just a backup to keep the nut tight.

Are you looking for a 19" pitch?

 

[Willyclay]

Re: Rubber Hub or not?

Just sent you a PM.

 

[tarheelebbtide]

Re: Rubber Hub or not?

No, I can't use a 19" pitch. Long story short, the mechanics around here tend to be crooked as snakes and somehow magically I ended up with the incorrect outdrive on the boat after a rebuild. I didn't know it at the time, just thought that I had an over rev problem due to more power after the rebuild and was under propped. Turns out, they put a 1.62 ratio Alpha One on. After discussion on the Merc I/O board, the consensus is that it can be propped back into correct specs without damage to anything because the 1.62 is so close to the 1.5 it should have. Now, it will turn about 5200 on the 350 Mag. I know it shouldn't go above 4600 or so, so I need to knock 500-600 RPM off of it. I'm thinking of going to a 23" prop to correct this issue.

 

[Dhadley]

Re: Rubber Hub or not?

Where are you located?

 

[tarheelebbtide]

Re: Rubber Hub or not?

North Carolina...eastern part of the state...pretty much sea level.

 

[Dhadley]

Re: Rubber Hub or not?

I have an idea that might help. I'll send you a private message.

 

[Dhadley]

Re: Rubber Hub or not?

Ah, just noticed - the correct spacer is there, it's just hard to see in the pic. I zoomed in and it looks OK. Sorry!