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Crank shaft pilot bushing

68 440+6 R/T

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Has anyone had a problem with the under sized crank shaft pilot bushing? I have one in my 70 roadrunner that has a automatic crankshaft and what i know is that 4 speed cranks had the input hole machined just a little bit larger then automatic crankshafts. When we went to put the clutch alignment tool in it (a scraped transmission input shaft) it was too small, before we installed the bushing in the crank we test fitted it on the transmission and it fit perfectly around the input shaft. Does anyone have any advise on how to enlarge opening “ID” on the bushing to get the transmission to fit?

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It will be tricky to open up that bush.
Perhaps get it out and use one of those bearing adapters that goes in the torque converter register.
I think Brewers sell them.
 
How about turning the OD of the bushing down on a lathe to make it fit the crankshaft?
 
You should be able to run a .750 hand reamer through it without too much trouble.

However, if it were me I would remove the bushing and install the roller bearing as Steve340 said above.

My crank had the hole drilled but not bored so it was undersized and didn’t run true. Last time I replaced it with the roller bearing and it has worked great.

I’m sure someone here has the part number
 
You should be able to run a .750 hand reamer through it without too much trouble.

However, if it were me I would remove the bushing and install the roller bearing as Steve340 said above.

My crank had the hole drilled but not bored so it was undersized and didn’t run true. Last time I replaced it with the roller bearing and it has worked great.

I’m sure someone here has the part number
FC69907
RockAuto
I've never seen the sealed Timken bearing before, has anyone used that one? When I changed the (non sealed) one in my '08 Ford at 150,000 miles, all the grease was gone and 2 needles were missing. Seems like the sealed bearing would be the way to go.
 
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I believe I used the National or perhaps FCA, but same style.

After 2 years of drag strip use it still looks good.

The Timken piece looks like a ball bearing and I don’t see why that wouldn’t work. Just don’t be fooled, Timken doesn’t manufacture ball bearings. It’s got to be from some company they have acquired.

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I would be careful about using a bearing and at least be sure your bell housing is as perfectly centered as possible. I’ve seen some pictures of badly mangled input shafts from rebuilders when a pilot bearing failed and came apart on them. I would try the wheel cylinder hone.
 
If the hole is deep enough and the bushing went in it all should be correct. The bushing fit the input before you installed it. When I blew up the picture the bushing has been slightly deformed from driving it in with the wrong driver in my opinion. You should be able to clean it up. If not remove it and drive a new one in with the right driver or as suggested a different style. Pretty hard to get it in straight with the bell in the way.
 
How about turning the OD of the bushing down on a lathe to make it fit the crankshaft?
I had this happen on a GTX in the 80s. I went to a transmission / machine shop for help. They suggested what Bib Bad Dad suggested. I measured the inside dia on the piolet hole in the crank and he trimmed the bussing a 0.003" pinch fit I believe (how am I remember that). To get the old one out i used a hack saw and cut a slot in the bushing to relive the pressure and slide it out. Hope this helps.
 
I had this happen on a GTX in the 80s. I went to a transmission / machine shop for help. They suggested what Bib Bad Dad suggested. I measured the inside dia on the piolet hole in the crank and he trimmed the bussing a 0.003" pinch fit I believe (how am I remember that). To get the old one out i used a hack saw and cut a slot in the bushing to relive the pressure and slide it out. Hope this helps.
I also ran into this years ago and had the bushing turned down to fit the crankshaft hole. Ran that setup for many years with lots of abuse and never had a problem with it.

Just double check that the crank hole is drilled deep enough to accept the full length of the transmission input shaft. Otherwise you're stuck with trying to decide if you really want to cut some of the tip off the 4 speed.
 
I'd say if you managed to get the bushing pressed into the crank then there was nothing wrong with the hole size. I'd chamfer the end of that pilot you're using and tap it into the bushing which should size the bushing. Maybe lube it up a bit beforehand and then give it a couple turns once its in. Bronze is soft enough to compress.
 
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