Ford pilot bushing problem

On a crank from the machine shop the pilot bushing isn't cut large enough for the proper pilot bushing. The proper pilot bushing is supposed to be 1.379 X 5/8, the hole in the end of the crank is 1.253.
Is there enough meat on a pilot bushing to turn it down to 1.253 X 5/8ths or should the engine come back apart and replace the crank.
Thanks, oj
This is a Ford FE motor.

 

Other than it will be a custom size, you can certainly turn down the bushing. The older Chevy bushings are something like 1.094 OD.

 

A few minute job with the correct tooling and a lathe.

 

I'd start asking what the crank came out of in the first place. I like the old Ford motors, but there's a lot of different pilot bushings for the different cranks. I'd put money on there being one to fit that application, unless it's an aftermarket crank, then who knows.

My thoughts.
Mike

 

I made a shaft to mount it on and turned it down. Once i actually saw how much meat it had there wasn't any problem. I had spoken to the guy on the telephone and i had the impression it was more dainty than what it really was.
Thanks guys, oj

 

Just make sure that the hole in the crank is concentric with the crank. I had a GM once where the crank hole wasn't finished to size and the unfinished bore ran out .010. Ya never know!

 

Ya gotta wonder if someone out there has recut one true, on a running motor I'd bet it is possible, with some creative jig.

 

Have a pair of "FE" builds in the pipeline, one 406" and one 352".

The 352" is an early one and the crank hole (pilot-bushing) measures 1.575", the 406" (1963) measures 1.850". I believe this also fits the 429" BB's?? Most of the "FE's" I've had here are the 1.850" x .670" dimension.

Never saw an "FE" with a 1.379" hole size. This is mostly the size from the SBF and the 6 cyl line! The pieces I have in stock with that measurement are also "roller" bearings!! There is more coverage using this size but no "FE's"?

Thanks, Gary in N.Y.

P.S. The above sizes are all "nominal", meaning within a "thou or two"!

 

I wondered about this as well. He said the crank is for an automatic, that is why it is smaller. I made certain to ask if the hole was machined or not.
I believe he said the engine is a 390, the input shaft was 1 3/8ths 10 spline. He regretted building that ****** and the ****** to that crank combo is odd. You know, Ford stuff.

 

something seems odd. According to my source Most Ford small blocks (including the Mod motor) from 1962-2013 use a 1.380"

Most FE's and 1971 and older 429 use a 1.851" X .671". Some early FE's, Y blocks, Truck 6 cyl and odd ball others did use a 1.576"

But I couldn't find ANY pilot bushing with a 1.253" OD. i wonder if it was an automatic crank that was not center drilled for a pilot bushing at all.

 

I've turned them down before on an arbor. You're only talking .063 off per side, .126 on the O.D., so it should be fine.

Bob

 

Ford made a change in the mid 60s. I can't recall all the details but I had to get a special Ford pilot bushing to use my 6 Cyl OD trans with a 66 352. It's a Ford part. No I did not memorize the pt no. sorry but it is out there.

 

If you are considering slightly turning down the outside diameter, long as the final 'fit' is correct, should not be a problem. It is a bushing, yes? if so just keep the dia's concentric.

 

So a question I would like to pose - does anyone know the diameter of the smaller surface at the back of a 390 crank (1967)? (see flywheel image with blue and red annotation)



Long story short, the input splines on the transmission (T-5 2004) runs about .400" beyond the face of the br*** bushing that is commonly found on these. I put a mean chamfer on the face to allow the splines to recess into the bushing, but the reduced contact surface I created on the ID of the bushing ended up getting smoked after a week of driving it. (see input shaft and br*** bushing images)



The bearings out of a 460 are smaller in diameter (1.378") and actually consist of a roller bearing nested in a sleeve. I plan on turning down the sleeve and knocking it into the smaller diameter marked in blue on the back of the crank. (see image of roller bearing sitting on top of the supplied sleeve)


Thus my original question - has anyone put a bore gauge on this surface to measure it (I don't have a bore gauge) or have a drawing showing the diameter? Can anyone confirm if this diameter is concentric or not? I have telescope gauges, but I'd like to do a .0005" to .001" press fit and my experience with telescope gauges is a +/- 0.002".

Any thoughts are appreciated!