273 Crank Shaft Pilot Bearing Solution

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jonn6464

1970 Duster
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Hey FABO,

If anyone is interested...

I had the machinist at my work turn down the pilot bearing, that would normally go into a small or big block crank shaft, to fit the smaller 273 journal.

Size is 1.556"

It tapped in with a socket over the face of the bearing. It is nice and snug.

We weren't sure what we'd find once he started taking material away, but it turns out to just be a solid race around the needle bearings. At least, it is solid up to the 1.556" point.

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Last edited:
Hey FABO,

If anyone is interested...

I had the machinist at my work turn down the pilot bearing, that would normally go into a small or big block crank shaft, to fit the smaller 273 journal.

Size is 1.556"

It tapped in with a socket over the face of the bearing. It is nice an snug.

We weren't sure what we'd find once he started taking material away, but it turns out to just be a solid race around the needle bearings. At least, it is solid up to the 1.556" point.

View attachment 1715921260 View attachment 1715921262

View attachment 1715921263

View attachment 1715921264
Nicely done. I will make this thread a sticky.
 
Cool! I have a 273 crank I may be putting into service and can use this trick. So it's just an INA needle bearing pressed into a larger solid hub...who'da thunk it?
 
Cool Stuff Jonn, and Charrlie.

Yes good for the Small Pilot Slants as well.
 
I just did this on my 1964 /6.

One thing to note, john6464 installed his bearing backwards, the lettering should face out because there is a lip seal built into the bearing. (See pic) It is packed with grease and the lip seal helps keep the grease in place.

I used an actual input shaft as a disc alignment tool and it actually made a suction sound when pulled out.

Also, mine measured a heavy 1.656 after I turned it down, maybe 1.6565. The press fit was a little on the heavy side. I would recommend a range of 1.656/1.655. This doesn't require a real extreme interference fit. Using a snap gage, my bore measured 1.653/1.654. The material is powdered metal so it comes off in powder form, not shavings.

I'm very happy with the result!

20220609_183625.jpg
 
I just did this on my 1964 /6.

One thing to note, john6464 installed his bearing backwards, the lettering should face out because there is a lip seal built into the bearing. (See pic) It is packed with grease and the lip seal helps keep the grease in place.

I used an actual input shaft as a disc alignment tool and it actually made a suction sound when pulled out.

Also, mine measured a heavy 1.656 after I turned it down, maybe 1.6565. The press fit was a little on the heavy side. I would recommend a range of 1.656/1.655. This doesn't require a real extreme interference fit. Using a snap gage, my bore measured 1.653/1.654. The material is powdered metal so it comes off in powder form, not shavings.

I'm very happy with the result!

View attachment 1715942976
I didn't know about the lip seal on the bearing. O thought the letters facing out was due to the tapered edge. But since that was gone once the bearing was turned down I didn't think it mattered. Now I know.
 
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