I have a Prestolite distributor in a 440/6 engine. We suspect the shaft is slightly bent because the shaft does not turn easily all the way around, it seems to hang up/drag at the same point in every revolution.

My local machine shop says they do not have the equipment to determine of the shaft is bent or not.

Any suggestions? Does anyone know where I could get a good, straight shaft?

I would undo it & a visual & spin it in your drill press. Ebay might be a source.

Thank you, RapidRobert.

I suspect the bend, if it is indeed bent, may be too small to see on a drill press.

I'll try e-bay, any idea what shafts will interchange with this one?

Take it apart and clean everything,it is pretty hard to bend the 1/2" diameter shaft,especially on the bottom end,possible on the top where the cam is located.Regardless it's an easy fix,I've been doing distributors a long time and I can only recall one and that was on the top and dropped on the cam.And on another note I would be a little skeptical of any machine shop that said they couldn't check it.

Thank you for your reply. Agreed, it would be hard to bend the shaft, if this one is bent, it's by a very small amount, just enough to cause drag at one point when turning it.

I've already had it apart and cleaned it. I also replaced the bushings.

Thank you, SRT, I'll contact these people if no one else has any suggestions.

They say 4-5 weeks for a rebuild.

what bushings did you use & did they require reaming? were they worn before, shaft had too much radial play (but no binding) & now after replaceing them they are binding?

RapidRobert, since I already had the thing apart for cleaning and inspection, I went ahead and replaced the bushings, no idea how many miles were on this.....

I used the same oilite bushings as were on it, the new bushings were about a 1/4 inch longer than the original bushings. No reaming required, they just pressed right in.

the reaming would be for the bushing ID once installed (if needed depending on the bushings used). are we on the same page? EDIT on the clocking where it ain't binding is it loose/tight/just right?

The ID of the new bushings was the same as the old.

The shaft spins freely, except for 12 0'clock to 1 0'clock, where it has some resistance/binding to spinning. I can easily turn it thru the binding/resistance with my hand.

Yes, we're on the same page.

Alright we're good. Grainger has an adjustable 15/32-17/32 straight flute reamer for $20 some dollars (I have one). One of the bushings is likely tilted a bit. for the price that would be my suggestion.

Good, thank you, I'll get one.

it is a 4LGR7 $20

One other thing,do you have any end pay at all ? If the collar is not actually actually flat on the top side it will give you the indication the there is a slight bind.

if your machine shop "doesn't have the equipment" to check the shaft to see if it's bent, i would get another shop for any work you need done !

If it was me, I'd run it and let the shaft/bushings "self clearance".

How "tight" is the binding?

Thank you, all.

I didn't notice any end play and I think the collar is flat on the end, but I can double check that.

The binding is just snug, I can turn it thru the binding spot by hand, it just does not turn freely.

What John K said! Usually when the collar is removed the roll pin will only go back one way,the collar turned 180* it isn't very likely,if it does and the holes are off the slightest amount it may give you what you are experiencing.