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Offline Don R

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RC rod issue,
« on: February 25, 2023, 03:48:30 PM »
 I pulled the pistons off my RC836 motor for a top end job, it has RC rebuilt Honda rods with bushed small ends and 12 point bolts. 
  That would be good, but the #4 small end rod bushing is turned slightly so the oil holes aren't lined up with the holes in the rod. The bushing appears to have been installed that way, the pin or rod end aren't blue, the bushing is centered in the rod, doesn't appear to be worn or willing to turn, the piston pin doesn't wobble in the piston or bushing either.
 So my options appear to be, drill the oil holes, or leave it alone since it lasted this long. Drilling would create a pair of #8 shaped holes in the bushing.
 Opinions?
 

 
 
« Last Edit: February 28, 2023, 09:03:04 AM by Don R »
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Offline Old Scrambler

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Re: RC rod Q?
« Reply #1 on: February 25, 2023, 04:26:41 PM »
With applied heat, I would attempt to remove the bushing and properly install it.............if not possible, drill it.
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Offline Tracksnblades1

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Re: RC rod Q?
« Reply #2 on: February 25, 2023, 04:29:06 PM »
Lightly heat rod end press out .
Let bushing cool in feezer or liguid no2.
Lightly heat rod end slip bushing in hold or pin align holes.
Let temperatures equalize.
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Offline scottly

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Re: RC rod Q?
« Reply #3 on: February 25, 2023, 07:02:39 PM »
DO NOT remove the bushing! When the bushing is pressed into the rod, the ID is compressed a tiny bit. After the bushing is installed, it is then honed to the final precise fit on the pin. Once you press the bushing out, you throw it away, press in a new bushing, and hone it to size.
Just drill the damn thing. ;)
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Online calj737

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Re: RC rod Q?
« Reply #4 on: February 25, 2023, 07:45:17 PM »
Quote from: scottly on February 25, 2023, 07:02:39 PM
DO NOT remove the bushing! When the bushing is pressed into the rod, the ID is compressed a tiny bit. After the bushing is installed, it is then honed to the final precise fit on the pin. Once you press the bushing out, you throw it away, press in a new bushing, and hone it to size.
Just drill the damn thing. ;)
Yup.
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Offline Don R

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Re: RC rod Q?
« Reply #5 on: February 25, 2023, 11:13:49 PM »
  Drill baby drill. I had no confidence the bushing could be removed by me without destruction.
 
  I think the oil holes are so close to lining up, drilling a small hole on a slight angle may feed oil into the interior oil hole with a small loss of bearing surface area.
  This motor is full of surprises, it had an aluminum RC Engineering head gasket.
  I'd like to get this one running for use while I'm building a higher HP motor.
« Last Edit: February 25, 2023, 11:27:51 PM by Don R »
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Re: RC rod issue, action decided.
« Reply #6 on: February 26, 2023, 02:14:15 AM »
New bushings installed by a shop that know how to do?
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Offline Don R

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Re: RC rod issue, action decided.
« Reply #7 on: February 26, 2023, 09:23:43 AM »
  Per, that obviously would be the best option, especially if I had split the cases. The automotive machine shops around here are mostly incompetent.
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Offline MRieck

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Re: RC rod issue, action decided.
« Reply #8 on: February 26, 2023, 01:24:03 PM »
I've seen the same thing in other RC modified OEM rods. The bushing hasn't spun in the bore but it has shifted.
Rod bushings are a bit of a science. Good buddy of mine worked in the balancing business for close to 40 years. He ran into shifting bushings and tried thicker bushings, tighter interference fit etc but it actually made things worse. The  RC bushings were too thick in his opinion. Look at a Carrillo  bushing....much different with a thin bushing.
I think that bushing will continue to shift but it might take so long that it doesn't matter. ;D
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Offline newday777

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Re: RC rod issue, action decided.
« Reply #9 on: February 26, 2023, 04:43:34 PM »
Quote from: MRieck on February 26, 2023, 01:24:03 PM
I've seen the same thing in other RC modified OEM rods. The bushing hasn't spun in the bore but it has shifted.
Rod bushings are a bit of a science. Good buddy of mine worked in the balancing business for close to 40 years. He ran into shifting bushings and tried thicker bushings, tighter interference fit etc but it actually made things worse. The  RC bushings were too thick in his opinion. Look at a Carrillo  bushing....much different with a thin bushing.
I think that bushing will continue to shift but it might take so long that it doesn't matter. ;D
Hmmm. I'll have to take a look at the set I bought last year.
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Offline Don R

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Re: RC rod issue, action decided.
« Reply #10 on: February 26, 2023, 05:46:17 PM »
 Crazy, I'll be sure they all get some assembly lube going back together.
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Offline Don R

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Re: RC rod issue,
« Reply #11 on: February 28, 2023, 09:04:07 AM »
 I was thinking, is there anything you guys have not seen before? What an encyclopedia of information this site is.
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Offline Ellz10

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Re: RC rod issue, action decided.
« Reply #12 on: March 01, 2023, 09:57:23 AM »
Quote from: Don R on February 26, 2023, 09:23:43 AM
  Per, that obviously would be the best option, especially if I had split the cases. The automotive machine shops around here are mostly incompetent.

We must live in the same area  ;D
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Offline Don R

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Re: RC rod issue,
« Reply #13 on: March 01, 2023, 10:27:34 AM »
Quote from: Ellz10 on March 01, 2023, 09:57:23 AM
Quote from: Don R on February 26, 2023, 09:23:43 AM
  Per, that obviously would be the best option, especially if I had split the cases. The automotive machine shops around here are mostly incompetent.

We must live in the same area  ;D
My brother tried both local shops, one ruined his VW crankshaft, the other turned his air cooled VW rods into water cooled VW rods. There is one guy 12 miles away that is competent but bought a liquor store and isn't interested in new work.
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No matter how many times you paint over a shadow, it's still there.
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