Small HP Con/Rod Fits What?

Joe Reeves

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Clearing out my remaining stock, I've come across a brand new small horsepower connecting rod of which I have no idea what it is, that is... what it fits.

It has a casting number on its side...... 388974-6 . Hopefully some one out there has a small horsepower engine tore down that has rods with that cast number on them to give me a starting point (Make, Hp, Year) whereas I can determine the interchanges with other models from that information.

Cast388974a.jpg


Joe
 

Faztbullet

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Re: Small HP Con/Rod Fits What?

I ran it thru BRP dealerport and struck out.. will keep looking. Is it needle brg rod????
 

Joe Reeves

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Re: Small HP Con/Rod Fits What?

It appears that it would need the two liners and needle set.
 

Haffiman

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Re: Small HP Con/Rod Fits What?

Looks like an 0383010 rod that fits most of the older (70's) 2 Hp engines. The screw locking tabs and big end bearing gone missing. Split and check for the dowel sleeve for the alignment. If there, 73 and earlier, if not 74 and later.
 

sschefer

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Re: Small HP Con/Rod Fits What?

Did a search on Boats dot net and nothing came up for any motor part they stock.
 
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Joe Reeves

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Re: Small HP Con/Rod Fits What?

Looks like an 0383010 rod that fits most of the older (70's) 2 Hp engines. The screw locking tabs and big end bearing gone missing. Split and check for the dowel sleeve for the alignment. If there, 73 and earlier, if not 74 and later.

No dowel pin mort, so if it's a 383010 (1.5hp/2hp), it would be for the 2hp between the years of 1974/1977. However, since the 1973 and earlier 1.5hp and 2hp also called for the 383010, I assume this "no dowel" rod would function properly those models.

Rough approximate measurements (I'm not a machinist) of the rod are: Length 3-3/8" - C/S Throw Hole 7/8" - W/Pin Hole 7/16".

Now, if I could just find someone with one of those models torn down to get the casting number off their connecting rod.

The 1978 model had a different part number and 383010 apparently does not supersede up.
 

Haffiman

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Re: Small HP Con/Rod Fits What?

Joe. If you have a closer look at the parts breakdown of 'connecting' parts, both piston pins and crank shafts are the same (superseeded) before and after 77. I believe what happened in 77 was that they went from casting to forged rods. Technically you may swap as you like, even before and after 77. The last number '6' indicates it comes from casting mold 6 in a multiple casting mold tool.
 

Chinewalker

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Re: Small HP Con/Rod Fits What?

I seem to recall the 1.5/2hp rods as being longer in proportion to, say, the 4hp rods of the same vintage. But, there really isn't much else it could be. I have a 2hp in pieces at my storage barn - if I remember, I'll see what number is on it this weekend...
 

Joe Reeves

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Re: Small HP Con/Rod Fits What?

I seem to recall the 1.5/2hp rods as being longer in proportion to, say, the 4hp rods of the same vintage. But, there really isn't much else it could be. I have a 2hp in pieces at my storage barn - if I remember, I'll see what number is on it this weekend...

Please do my friend. I would really appreciate that.
 

Chinewalker

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Re: Small HP Con/Rod Fits What?

Hi Joe,
The number on my 2hp Rod is 382283. For reference, it measures about 2-3/4 inches on rod to wristpin centerlines...
- Scott
 

Joe Reeves

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Re: Small HP Con/Rod Fits What?

I apprciate the measurement info. The rod in question that I have (cast 383974-6) measures approximately 2-7/16" on rod to w/pin centerlines.

Looks like I'm back to square one. If your rod has the dowel pin alignment for the rod cap, that would explain the casting number difference (mine does not have the dowel) BUT I would think these measurements would need to be identical.
 
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