Need Help with Prop Hubs - Removing and Replacing Hub, Etc

enginesilo

Petty Officer 1st Class
Joined
Jun 9, 2008
Messages
355
I can use some help with 2 props I have. The first prop is the original prop that came off of my boat. The second is a spare prop I got used with a lower pitch that I'd like to try to install for this season. I don't know much about props, but I think they may have different hub setups. Can someone take a look at the pictures below and explain if I can swap the hub from my current prop over to the replacement? Seems like they are different hub systems but i'm unsure. Or does it make more sense to buy a new hub for the replacement prop to be compatible?

I don't know the technical terms, but my existing prop had the round metal thick washer ring in the back side that I took out, and I think its a rubber sleeve inside? This replacement prop seems to have a brass fitting of some sort throughout the prop.

I read that some hubs are rubber and need to be pressed out with a machine press. Can I do this on my own or should I bring it to someone to have them swap the hub or put a new one in? Can this replacement prop be used with the right hub installed? Any tips appreciated.

Here are some pictures of each prop front and back

Existing Prop Front and Back
tvzcSyw.jpg

TXxhk4K.jpg


Replacement Prop Front and Back
NahaP0E.jpg

xaOLSoq.jpg
 

Boat Doctor1

Petty Officer 2nd Class
Joined
Sep 29, 2012
Messages
123
The one with the flat type "brass" looking bushing =likely is an aftermarket "Michigan" brand prop. Takes a diff washer all flat -other prop is oem omc type =takes a standard stepped washer! Cant interchange those hubs!! likely just need a new prop or have those redone to what u need!
 

enginesilo

Petty Officer 1st Class
Joined
Jun 9, 2008
Messages
355
The one with the flat type "brass" looking bushing =likely is an aftermarket "Michigan" brand prop. Takes a diff washer all flat -other prop is oem omc type =takes a standard stepped washer! Cant interchange those hubs!! likely just need a new prop or have those redone to what u need!
You are exactly right. The existing prop is an OEM Merc prop. The replacement prop is a prop I picked up for $5 on Craigslist that had the right pitch I was looking for. Would it be worth taking the hub out of the Michigan and installing the other type hub? Or am I better off just buying a new prop with the correct hub already installed? I was hoping to get away with just buying a new hub so I could see how this prop performs since is a slightly lower pitch that people said would give me a better ride.

EDIT: After searching around Google, I think the Michigan Wheel prop may have a pressed in hub, and that prop is not compatible with the rubber type hub. Is that accurate? Guess i'll be shopping for a new prop then. Or can I just change out the thrust washer and use this prop, or is that not an option?

I saw this site says this may be a Black Max Series Prop and they sell a thrust washer that is pictured. Would that do the trick on an alpha 1 gen 2?
http://www.mercstuff.com/thrustwashers.htm
 
Last edited:

enginesilo

Petty Officer 1st Class
Joined
Jun 9, 2008
Messages
355
The one with the flat type "brass" looking bushing =likely is an aftermarket "Michigan" brand prop. Takes a diff washer all flat -other prop is oem omc type =takes a standard stepped washer! Cant interchange those hubs!! likely just need a new prop or have those redone to what u need!
So pushing this further to see if I can use this prop, would it be safe to say that if I get these parts I can use this replacement prop? Looks like the thrust washer form my current prop may be the same so I can reuse that? I then see part #D (Continuity Washer) and part #E (Spline Washer) I'm guessing I need to buy.

Can I get those 2 parts D and E in the Typical Prop setup diagram, and use my existing thrust washer and call it a day?
Looks like the Spline washer part E #12-31211a2, and I'm not sure if part D is even used since I couldn't find anyone selling it.

Replacement Prop Setup
HtFecOm.png


Current Prop Setup
dxwcZkx.png
 
Last edited:

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,659
On using your existing thrust washer, it depends on how things line up. From what I can tell of your current prop it is a plastic/brass replacement hub like your lower cartoon and is chewed all to pieces. Doubt it would push your boat. Second prop looks like a rubber pressed in hub (that a prop shop needs to install with the proper equipment if you want to change things up) supported by your first cartoon. Any boat dealer of your make of engine will have parts lying around that he'll sell you to make the new prop fit.

Fit means that once you have the parts in your appropriate cartoon, there is a short distance of prop shaft threads, maybe 7/16 to 1/2" remaining behind your nut after torqueing to 55 ft lbs. I'm confused in your first cartoon that pertains to a rubber hub about item "d". My prop lineup for a rubber prop was: Thrust washer item "b" turned in the direction whereby the taper of the ID of the washer fits the taper of the prop shaft, then the prop, then item "e" which is splined to fit over the protruding splines of the prop shaft with the back of it with 3 detents, 120 degrees apart, then item "f" which is a locking washer that has 6 ears on it and a detent for the prop nut item "g" to fit into and once you have your 55 ft-lbs (pretty tight), you continue to turn the prop nut until you can push 3 of the 6 ears into the slots on item "e" which acts as a secondary prop nut locking mechanism. The first mechanism is the nylon insert in the prop nut itself.

​Mark
 
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