Fixing wrist pin bushing bore in connecting rod?

[cjtoombs]

I guess if I didn't have the equipment to fix that, I would run it down the street to my local automotive machine shop and have them put in a new bushing. Just hand them the rod, the old bushing, and the new pin. They can hone the rod then create a new bushing that will fit.

Or as Mike says, JB weld would work also.

Honning wouldn't' work very well, since that is basically a slot and those honing machines don't deal well with slots (Sunnen makes special mandrels for honing holes with keyways, but automotive machine shops have no need for them). You would need to find a shop with a rod boring machine. I would be a bit worried about weakening the rod by boring it. I think the JB weld, or even just locktighting the new bushing in would be fine. As thick as that bushing is, it should structurally bridge that gap.

 

[royesses]

Braze the rods worn area, rebore and install new bushing.

Roy

 

[NortonDommi]

"Honning wouldn't' work very well, since that is basically a slot and those honing machines don't deal well with slots (Sunnen makes special mandrels for honing holes with keyways, but automotive machine shops have no need for them). "
It is the little end bush that gets honed and it has a round hole in it.
Forgot to say earlier that many compressors are splash lube so would be a good idea to look at why there was so much wear apart from lack of maintenance.

 

[fixit]

Did anyone consider a NEW connecting rod? I did repairs on air compressors for years (1/2 hp piston to 2000 HP 7600 volt driven centrifugal machines) I would never take a chance a weakened connecting rod. If that thing breaks it will tear up the piston & cylinder. But it's your machine & that's my 2 cents.

 

[royesses]

I can still get a new wrist pin and bushing, but the cast iron connecting rod is no longer available new and I have not been able to find a NOS or a used one so far.

New would be best but he can't find any new or even a used con rod.

Roy

 

[Flyinfool]

As is, the compressor is junk, a replacement part is not available to do it right. I would scuff up the bore of the con rod, especially the area that is worn, with same coarse sandpaper, scuff up the OD of the bushing, clean both to within an inch of their lives, and then JB weld the bushing in place.

The wear area is so small that it would probably be fine to just stuff in the bush and call it close enough, JB weld is tough stuff and should hold up just fine. You will never get the bushing out again, but with proper maintenance you should never have to. worst that can happen if it fails and the rod breaks is you are bak where you are now, the compressor is junk. But you have taken your best possible shot at a repair.

I would not try to braze the area and rebore, the heat will change the temper of the alumnum and may aneal it (Yes some alloys of aluminum can be heat treated and or annealed) and that could cause a failure.

 

[FOMOGO]

The con rod is described as cast iron, or more likely a forging. Mike

the heat will change the temper of the alumnum and may aneal it (Yes some alloys of aluminum can be heat treated and or annealed) and that could cause a failure.

 

[cjtoombs]

"Honning wouldn't' work very well, since that is basically a slot and those honing machines don't deal well with slots (Sunnen makes special mandrels for honing holes with keyways, but automotive machine shops have no need for them). "
It is the little end bush that gets honed and it has a round hole in it.
Forgot to say earlier that many compressors are splash lube so would be a good idea to look at why there was so much wear apart from lack of maintenance.

See the picture of the little end of the rod. The problem isn't sizing the bushing, it's the slot worn in the rods small end.

 

[ezduzit]

I would rebore the hole oversize, make a new bushing and resize the bushing ID to fit a new wrist pin; I would definitely not use epoxy to take up the wear.

This. I would not Mickey Mouse it with epoxy.

 

[hhscr]

Thanks for all the ideas.
I mis identified the connecting rod as Cast Iron, it is as already suggested forged.
I will be taking it to a local automotive machine shop tomorrow to see if they are equipped to make a solid repair.