Can anyone identify this prop?

[B.Leonard]

Came with the 235 on my Sterling.

part# 48-76108-28

-BL

[B.Leonard]

Looks like the hub was trimmed down. The notches were cut to clear the blow-out ring that's on the lower.

-BL

[B.Leonard]

-BL

[Scream And Fly]

Looks like an old-style inline chopper. The weedeaters were chopped off too, as you noted. Also known as a "Small Ear" chopper. That's an OLD prop.

Why were the blades chopped too?

Greg

BTW, your decals are on the way!

[LaveyT]

The old inline Choppers were "THE" prop to have in days of old.
Accelleration was excellent.However,When used on higher H.P.
motors they had a disconcerning habit of converting themselves
to un-balanced two blade props.:rolleyes:
The little smile dude is wondering where his blade will come down.

[B.Leonard]

What is meant by that? So it is an OMC prop? It looks like there isn't a prop recon shop it hasn't been to :rolleyes:

We'll see how she runs this weekend. :)

-BL

PS Thanks Greg!

[Scream And Fly]

It's a Merc prop. They are called inline Choppers because they were really popular on the Merc inlines back in those days. The V6 motors usually used the large ear Choppers.

: )

Greg

[Laker]

Inline 6 merc Chopper.
Made for the 100 CID In line 6, If thined at all they would come apart like LaveyT said.. really bad with a big motor.
Many times this is blamed on the Prop Tuner but they were on the edge stock, Thined they started to Crack

[Mark75H]

Merc part numbers that start with 48- are props, so anytime you see 48-xxxxxwhatever you are looking at a Merc prop.

48-76108-28 would of course be a 28" pitch prop when it was new...probably suffixed A-2 or A-4 meaning "cupped"

At first Merc used A-2 for a little cupped and A-4 for lotsa cup...did they ever use A-6 for so much cup it might as well be curved back on itself?

Odd number suffixes on props (or any Merc part number for that matter) just indicate some other change or variation from the original base part number.

[Raceman]

A little 'mo history: In the early 70's Merc had 2 real good over the hub blades. Both had round ears, one being 2 blade, the other 3. The 3 blades were called Elephant Ears by some folks. Both had a terrible time with throwing blades and the 2 blade would also beat out the gearcase causing the propshaft to pop out, losing the whole thing. So along came the cleaver. The first cleavers wouldn't run with the old round ears and the racers were paying mega bucks for the round eared stuff. The lifespan of the round ears, especially on the tunnels, run real high was REAL short and the supply was rapidly diminishing. The cleavers would stay in one piece and the J sport guys started making them work. This was the fastest class running a full sized gearcase. I don't know if they worked the props differently, or just discovered that they would run higher than the round ears, but they became generally accepted. I've never been sure that the best cleavers would in fact outrun the 2 blade round ear, especially on a V bottom.

The cleavers didn't work great on everything, especially the fast bass boats. As best I remember, the chopper came along about the same time as the V6 Merc in '76, but it could've been a little sooner. It was the best thing available for anything that needed bow lift and there was only one style available at the time, the one that we now refer to as the inline chopper. It was all we had to run on the first V6's, and did in fact sling blades about as bad as the older style round ears. Later came the V6 style chopper and I've yet to see a boat that it's faster on myself, but have been told by folks at Merc that it is on a heavy boat because of it's greater blade area. Supposedly it's a good bit stronger than the inline chopper also.

One thing that I never heard before was the difference in part numbers for the amount of cup. Always wondered what those suffixes were.

[B.Leonard]

Wow! I'm impressed! :) It is an A4. That is the suffix and it's stamped right on the side of the hub.

The blades are thin and sharpened. I hope for my buddies at Palatka that the ol' 235 can't spin this bad boy hard, but she doesn't have rev limiters :eek: :D

I noticed the good amount of cup and thought it was strange for someone to be running that on a tunnel. I'll bet it helps it out of the hole though.

-BL

[pyro]

So, somebody please tell me what the differences are in the in five numbers between 48- and A2, A4, etc.
Mine in a 28" 48-13372 A5.

[LaveyT]

fast Eddie has a story about slinging a Blade he swears is true.
He said they felt the vibration and loss of thrust,turned it off,
went to the rear of the boat to look for damage and Heared the blade hit very close by:eek:

[Glenn]

Same hear Pyro. I'm sure It's been posted before. Can't remeber. Mine is 48 13370 A5 26P.

Glenn

[Mark75H]

Sorry there is no key to the prop's identity in the 5 middle numbers. They are assigned to a prop in order as it is designed. They may be in the master "Where Used" book, however, I'll ask. In general the "Where Used" book tells which motors a part fits on.

The A5 suffix might mean cupped and thinned or some other variation of the blade shape....I don't know if there is a strict rule on the odd numbers.


On parts other than props, a suffix letter means a slight change from the original part so close that a new number was not assigned. Something like a change in the vendor/supplier or slight change in alloy, slight change in shape that fits exactly the same (upgrade for strength, etc). So if you had the original part and went to your dealer to pickup a replacement and the part number now has an A or A-1 and for example a spring....the new spring looks a little different...a little fatter or thinner or shorter or longer, but it will still fit......the spring is the correct one even though it is different, there was a change.

[Doubledog]

You added this to the history channel, oops, I mean the history forum yet? Good stuff here. Thanks

[Bill Gohr]

The 14' diameter choppers came out in 75 I think. The first ones were blade slingers. Then they changed the material. This is identified on the thrust hub surface of the prop. There is a round cast hole it will contain a "D" or a "5". d's are blade slingers 5's are the good ones. As for the 14.5 choppers the different "A" numbers relate to the hub designs. The smaller eared chopper still is the fastest top end prop on a light boat.

[B.Leonard]

What are you guys, the Scream and Fly psychic prop line? :)

After risking stiches from this torqued on, knife edged artifact and digging through a layer of crud in a small hole on the back of the hub... sure enough, plain as day... "5" :rolleyes:

-BL

[Bill Gohr]

Lucky guess hey, That's a good one. Really I just wanted you to go out and get your hands dirty. When I raced my Lazer with the crossflow at the Island ( for 3 years ) I ran either that prop or a 30. Why they cut the knotches in the blades is beyond me.

[B.Leonard]

It's cut to clear the blow out ring that is on the lower. The lower has a blow out ring and a torque tab.

That prop seems to work pretty good. It's hell out of the hole though! With 1 passenger sitting in the back, almost impossible to get on plane.

-BL

[Bill Gohr]

We used to put a little roll in the blade to fix that. I would put the correct spacer behind the prop to make it clear and keep it as close as possible.

[B.Leonard]

The prop calc says the inline is more like a 29-30" It has a fair amount of cup so maybe that's causing the seemingly higher pitch effect.

How would my 27" Shooter work? Seems like the motor could use a few more Rs (it runs between 5600-5800) and I know that Shooter would kick butt out of the hole.

-BL

[Mark75H]

Many Merc props are a little higher pitch than they are marked, what you see is not unusual. Merc had their own proprietary pitch blocks to work the props. If you lay a Merc prop on someone else's block it usually won't match, to do a Merc prop right, you gotta have a Merc block.