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Honable / Borable Connecting Rod Bushings


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I'm restoring a 1466 and as part of that project, doing a rebuild on the motor. Was going to order connecting rod bushings and came across some marked honable and others market borable and some not marked at all. According to Reliance: "Connecting rod bushings will distort slightly when pressed into the small end bore of the connecting rod. Therefore, connecting rod bushings must be sized after being pressed into the rod by using one of two methods depending on the shop equipment available. The difference between honable and borable connecting rod bushings is the size of the inside diameter. Borable bushings are approximately .020” smaller inside. This extra material allows the properly equipped machine shop to bore the bushings “on center”, thus restoring the connecting rod to it’s proper center to center length. Honable bushings have a few thousandths of an inch of extra material on the I.D., and must be honed out after the bushing is pressed into the rod. These honable bushings are a great alternative for smaller machine shops and independent mechanics not equipped to bore the rods."

On my last tractor motor rebuild I outsourced the connecting rod bushing replacements. Not sure it they pressed out the old and pressed in the new and that's it or if the sized them afterwards. For those that have done your own, do you hone/bore yours?

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Unless you have a rod bushing honing machine DO NOT replace them yourself. 400 series engines have a trapezoid shaped bushing.  You have to have the proper tools to press them in, and then if you don't hone them square with the bearing end, you'll have big problems.  Outsource it if bushing replacement is necessary. 

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All IH wrist pin bushing I have ever replaced needed resizing I have a wrist pin hone so that's what I do But some shops around have boring equipment

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2 minutes ago, J-Mech said:

Unless you have a rod bushing honing machine DO NOT replace them yourself. 400 series engines have a trapezoid shaped bushing.  You have to have the proper tools to press them in, and then if you don't hone them square with the bearing end, you'll have big problems.  Outsource it if bushing replacement is necessary. 

400 series engines have barrel type bushings 8.3 Cummins have  trapezoid.

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13 minutes ago, R190 said:

400 series engines have barrel type bushings 8.3 Cummins have  trapezoid.

That's right, but in my defense the dt466E engines were trapezoid. 

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1 hour ago, J-Mech said:

That's right, but in my defense the dt466E engines were trapezoid. 

yes    out of curiosity have you ever seen a dt466e in anything but a truck I have not

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Another reason for heavier thicker bushings is to restore the center to center distance of large end to small end of the rod when you refinish the large end.   Also, you can cheat a little if you need to change the piston height over the block when you have a heavy bushing.   Not all crankshaft journals stroke  are  exactly equal  , especially after a regrind of shaft when shaft has been straightened. 

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Interesting tidbit here.  I have on a shelf a connecting rod reboring tool.   NOT for the bushings, for the crank end.   I bought the toolbox with it in on an auction because it had a couple dial indicators in it, and it went for $5.   Took me a while to figure out what the heck it was.   Apparently back in the day, when your not-snap-in bearing connecting rods would wear eggshaped, you could grind down the ends of the cap & fork, bolt them back up, and then rebore the rod to crank surface to true again.   The boring tool shaft has about a 100 threads per inch so it advanced real slow!

I'd really be interested to know if any of you have ever used or seen one of those before?

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3 hours ago, Jeff-C-IL said:

Interesting tidbit here.  I have on a shelf a connecting rod reboring tool.   NOT for the bushings, for the crank end.   I bought the toolbox with it in on an auction because it had a couple dial indicators in it, and it went for $5.   Took me a while to figure out what the heck it was.   Apparently back in the day, when your not-snap-in bearing connecting rods would wear eggshaped, you could grind down the ends of the cap & fork, bolt them back up, and then rebore the rod to crank surface to true again.   The boring tool shaft has about a 100 threads per inch so it advanced real slow!

I'd really be interested to know if any of you have ever used or seen one of those before?

Seen a crank turning tool in a book for the rod journals. It was hand held any you turned crank with electric motor and belt. The tool had a bit and handle it basically turned crank down in car. You then rebabbited rods and away you go.

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