Mercury prop slipping, right prop/parts? HELP!

Hello all;
I have a 22' 1974 Starcraft Chieftain, Aluminum hull, I/O, 165 Merc/GM Inline 6 (250ci), Mercruiser drive, pre-Alpha, think model 165? Drive ser. #3647773.
Prop is a three blade 16" #48-16440-c1-16 stamped on the prop, new, 16" pitch. Hub kit I have is a Mercury Flo-Torq #835257A1. I googled the prop number and it came up as a black diamond alum. prop.
I just bought this boat, and put it in the water for the first time yesterday. I torqued the prop nut to about 45ft. lbs. As soon as we tried to leave the dock the prop was just spinning on the shaft. Worked at first, and then quit working before we could even get underway!
I took it all apart, and everything looks ok, but I'm wondering now if this is the right prop/hub kit? The prop and hub kit came with the boat, and I installed it all but this is my first time
Boat weighs around 2000lbs.
I know the drive is original to the boat, has the lifting eye on the top of the drive, so it's pre-Alpha one.
Thanks in advance for the help!!

David Sexton

Re: Mercury prop slipping, right prop/parts? HELP!

but I'm wondering now if this is the right prop/hub kit? The prop and hub kit came with the boat, and I installed it all but this is my first time

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Ayuh,... Got a Picture of all the pieces,..??

There should be the thrust hub,...
The plastic insert,...
The bronze splined insert,...
The locking washer,...
And, the nut...

If ya got all those pieces installed, 'n it still don't turn, under power,...
I'd guess you've got a Drive problem...

Re: Mercury prop slipping, right prop/parts? HELP!

Yeah, I shoulda included those in the first post... probably would've helped!
So, in researching today, one thing I know for sure is that I am actually missing a piece from the Mercury 835257A1 kit, the black "delrin" piece that goes in the middle of all this. Pretty sure this is my problem...
However, I have talked to others that say the first gen. Mercruiser drives (pre Alpha One) used a prop that was splined to the shaft, and had a rubber slip ring, kind of like a vibration damper built in in case the prop hit something. The prop I have is not splined. It has a rounded/square shaped hole in the middle, for the black Delrin piece to fit into I believe.
Mercury's website explains the "Flo Torq II" which is my hub kit, as a newer setup, but lists it for my boat/drive.
So, question is, do I need to buy a new prop which is splined to the shaft, or do I have the right stuff and the prop adapts to my drive with the "Flo Torq II" kit?
I'm actually waiting on the last picture to download, but i'll put that on asap.
Thanks!

Dave

Re: Mercury prop slipping, right prop/parts? HELP!

So, question is, do I need to buy a new prop which is splined to the shaft, or do I have the right stuff and the prop adapts to my drive with the "Flo Torq II" kit?

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Ayuh,... All of the Alpha series of drives use the same props...

In the 1st pic, the thrust hub is still on the prop shaft...
In the 2nd pic, Who cares 'bout the Box, it's what's In it that counts...

When ya put all the parts together, that prop will fit on yer drive...
The plastic takes the place of the old rubber hub...

Re: Mercury prop slipping, right prop/parts? HELP!

What all came in the Flo-Torq II kit you have? Seems you are missing some parts and using some wrong ones. I'm using the Flo-Torq II kit for an Alpha4 prop on a MC1 drive like yours. The thrust washer you have sitting on the prop shaft (pic) looks like the old thick style, when I'm guessing you need to use thin one from the Flo-Torq kit,,,, along with the other parts.

Here's a pic of the Flo-Torq II components;

Re: Mercury prop slipping, right prop/parts? HELP!

Okay, here's the pic of all I had. I know now that I am missing a piece. Isn't learning great!! Ordered a new kit yesterday. And it seems from what I can find that this is a "two-piece" type prop, whereas the originals are a "one-piece" design?

Re: Mercury prop slipping, right prop/parts? HELP!

Oh, and the picture of the drive on the boat was before I got the boat home. I just bought it a few months ago. So, the washer on the drive is no longer there, and I had installed the thinner one that came with the kit, the brass insert and the locking/tab washer and nut. Just didn't have the aforementioned black delrin piece.

Re: Mercury prop slipping, right prop/parts? HELP!

Thanks fishrdan and bondo!!

Re: Mercury prop slipping, right prop/parts? HELP!

Got the new hub kit and installed! No problems now Black piece definitely imortant!

Re: Mercury prop slipping, right prop/parts? HELP!

sextondm said:

Got the new hub kit and installed! No problems now Black piece definitely imortant!

Click to expand...

Ayuh,.... It's Important too...