I have a 68 C3 4 speed that has had an engine swap from the 327 to a 454. I bought the car a year ago and decided to rebuild the engine. The 454 was a low compression 74-75 year engine. I had trouble separating the transmission from the engine when I removed it. The pilot bushing came out of the crank with the transmission. It was loose fitting on the input shaft and had been spinning in the crank. A new bushing press fit into the crank ok. As far as I can tell, when the engine swap was done, they used the 327 bellhousing and flywheel with a balance plate. I installed a new 454 flywheel and 11" clutch and again had a hard time installing the transmission into the pilot. My question is, is it possible that the bellhousing is slightly mis-aligned with the engine? Should I be buying a big block bellhousing? I didn't think there was any differences, but my input shaft is sticking or draging on the pilot and the clutch will not fully disengage. Help!

 

Yes it is very possible. That is why I always align the bell housing when putting an engine and transmission back together. There are several Utube videos on how to do this.

 

It's typically called "dialing in a bell housing" for reference to the videos Gordon mentions.

 

just went thru a similar problem new pilot bushing stuck on input shaft and spun in crank, I had dialed in the bell so I looked at the diameter of the inside of the bushing with a snap gauge and it was undersize, it had fit fine until I drove it in and it was enough to slightly crush it, cleaned it out with a reamer and the trans would slide right in.

 

I always have trouble aligning the tranny and the bellhousing in the car. I pull the engine then the tranny seperate, buy when i install them, i assemble them outside the car and insert them as a unit.

 

Thanks for the advise everyone. I have never run into this before. I guess I was just lucky, 14 years working in a Ford dealership and never ran into this on any make

 

If the trans does not slip right in....the clutch plate is still slightly off......very common thing......using crap plastic clutch alignment tool that is sloppy at best. Get a piece of cut off input shaft and do it that way. Simulates the trans being slipped in as you tighten the pressure plate.
My own 406 has a McCleod clutch and when I was putting the Muncie on....it hung up a bit.....so I pushed on the fork real hard and it relieved enough pressure for it to slip right in.
Aligning a bellhousing is a good thing but remember GM built millions of stick shift cars without doing it.........

Jebby

 

if the engine is in the car just have someone disengage the clutch by pushing in the clutch pedal so the clutch disk free floating so the trans input shaft goes into the pilot bushing

 

Make sure you are using an oilite bronze bushing. Many of the over the counter bushings are steel. Check your bushing with a magnet. It should not be magnetic. Auto Gear on the forum makes oilite bronze pilot bushings. They will make them to size for your crank and trans.

Tom

 

FWIW - Autogear sells excellent parts and I am a repeat customer. I keep a stock of their pilot bushings here at the house in case I ever need them. The bushings they sell are listed as "Oilite" but they are not actually made of "Oilite". They do appear to be brass or something similar and they are not magnetic. Best pilot bushings I have been able to locate.

Oilite is a sintered porous bronze material that is impregnated with oil. Cant easily find them anymore. Looks more like a porous bronze carburetor filter only denser.

 

Interesting. They do look like machined brass but they are impregnated with oil so I thought they were oilite. I actually heated one on the stove, wife wasn't home, and watched it sweat oil. I also keep a couple just in case.


Tom

 

good to know. Maybe a newer version of Oilite.

 

TWO COMMON MISTAKES WHEN REPLACING A TRANSMISSION/PILOT BUSHING.

PILOT BUSHING.
There is front and a back side to the pilot bushing, One side of the bushing hole is tapered (or chamfered if you prefer). THE TAPERED END OF THE HOLE NEEDS TO FACE THE TRANSMISSION----------------------makes it easier for the input shaft to be guided into the bushing.

CLUTCH ALIGNMENT.
When installing/replacing a clutch --------------------------------BEFORE TIGHTENING THE 6 ATTACHING BOLTS---------------------------insert a line up tool so that the clutch disc is properly indexed with the center line of the crankshaft/bushing.
MANY clutch kits come with a plastic line up tool-----------------THROW IT IN THE TRASH! Locate an old junk transmission input shaft (3sp or 4sp, doesn't matter) to use as a line up tool and be sure it is fully bottomed out in the bushing. Alternately rotate the flywheel and tighten the 6 clutch bolts.
If the clutch disc is properly centered and bushing is installed with the tapered end of the hole facing the transmission, then shift the transmission into a gear and insert an old driveshaft yoke into the rear of the transmission so that it can be rotated to rotate the input shaft so that the input splines line up with the splines in the clutch disc. It should slide right in with almost no hassle.