Pilot bushing diameter Help needed!

[Ron Dame]

Short version: I need the outside diameter and depth of a truck pilot bushing. It may be different than in cars, since it has a heavier transmission, but I'm not sure. I'm also not sure if the input shaft size is different.

Longer version: The '63 Champ 6 cylinder (8E5) uses the V8 bellhousing, clutch, and pilot bushing. These later truck 6's have the pilot in the crank, just like the V8's. I'm putting a 185" crank and pistons in an OHV block, but the end of the 185 crank is not bored to accept a pilot bushing. The old 170 crank was beyond saving and has been scrapped. I forgot to order a pilot bushing, and yet the crank and other spinny parts are going to the shop in the morning to get balanced. I'd like them to bore the pilot bushing hole while they have it, so I need to know what diameter and depth I should have them bore it to.

Thanks for a quick response!

rondame@bellsouth.net

Ron

Ron Dame
'63 Champ

[r1lark]

quote:Originally posted by Ron Dame

Short version: I need the outside diameter and depth of a truck pilot bushing. It may be different than in cars, since it has a heavier transmission, but I'm not sure. I'm also not sure if the input shaft size is different.

Longer version: The '63 Champ 6 cylinder (8E5) uses the V8 bellhousing, clutch, and pilot bushing. These later truck 6's have the pilot in the crank, just like the V8's. I'm putting a 185" crank and pistons in an OHV block, but the end of the 185 crank is not bored to accept a pilot bushing. The old 170 crank was beyond saving and has been scrapped. I forgot to order a pilot bushing, and yet the crank and other spinny parts are going to the shop in the morning to get balanced. I'd like them to bore the pilot bushing hole while they have it, so I need to know what diameter and depth I should have them bore it to.

Thanks for a quick response!

rondame@bellsouth.net

Ron

Ron Dame
'63 Champ

Ron,

The 7E-8E truck parts book lists the pilot bushing for the 8E5 & 8E10 trucks as 510168, and notes that the bushing is located in the crankshaft.

p/n 510168 is also listed for the '59-'64 V8 car, and also the 7E-8E V8 truck. So, the 8E six cylinder used the same pilot bearing as the V8s.

So, the diameter of the hole you need is the same as in a V8 crankshaft....but this still does not tell you how deep to go.

Paul
Winston-Salem, NC
Visit The NEW Studebaker Skytop Registry website at: www.studebakerskytop.com

[Ron Dame]

Thanks Paul, but it also does not answer the diameter the crank needs to be bored to. Remember, I forgot to order a bushing, and I don't have a crank to measure.

Ron Dame
'63 Champ

[Guest]

Ron - If you can get to a NAPA, get a #615-1157 bushing and mic it.
I have this one in service in my 7E7 Champ V8. It was only a few bucks.

[Ron Dame]

Cool! Thanks!

Ron Dame
'63 Champ

[r1lark]

quote:Originally posted by Ron Dame

Thanks Paul, but it also does not answer the diameter the crank needs to be bored to. Remember, I forgot to order a bushing, and I don't have a crank to measure.

Ron Dame
'63 Champ

Ron,

I have a 1985 Dorman catalog. It shows the V8 pilot bushing as 690-005.

They also have a dimensional table in the catalog, which gives the following for p/n 690-005:
Inside diameter: 0.753"
Outside diameter: 0.940"
Length: 0.880"

Hope this helps you out.

Paul
Winston-Salem, NC
Visit The NEW Studebaker Skytop Registry website at: www.studebakerskytop.com

[Ron Dame]

Dat's zactly what I needed! I'll give that to the shop and let them bore to hold that.

Ron Dame
'63 Champ

[Alan]

6 cylinder is .8125" or 13/16". for the hole in the crank or flywheel and the pilot is .815" a .0025" press fit. Made one for Jeff T. a couple of weeks ago, never herd back from him if he ever got it or if it worked for him.

[Ron Dame]

quote:Originally posted by Alan

6 cylinder is .8125" or 13/16". for the hole in the crank or flywheel and the pilot is .815" a .0025" press fit. Made one for Jeff T. a couple of weeks ago, never herd back from him if he ever got it or if it worked for him.

That's fine for a 6 cylinder car, even a taxi, but the 8E trucks use V8 everything: bellhousing, flywheel, clutch, pilot bushing and transmission. Some of the late 3E's did as well.

Thanks anyway!

Ron Dame
'63 Champ

[Jeff T.]

Ooops,

Sorry Alan, I received the bushing but with my projects in unheated garages or outside, most of my Studebaker work has ceased until spring. It got down to 4 degrees above zero Thursday night.

Very nice work

Jeff T.

"I'm getting nowhere as fast as I can"
The Replacements.

[Ron Dame]

Well, everything is at the shop now to be balanced, it should be ready Friday.

In other news, I put the Stromberg WW on the engine in the truck, Overall it works well. Where the old RBS carb was asthmatic over 4000 RPM ( that is ALL it would spin) the WW lets the little 6 spin up to at least 5000, except my linkage geometry is off, and it goes over center and gets stuck in WOT (:-O . I don't plan to spin the old engine over 4,000 anyway, just in case there is a ridge at the top of the cylinder. I'd hate to break a ring in this decent stock engine. I also have a bit of a stumble at part throttle acceleration, I guess I need to change the power rod sprigs to something lighter? ...that's for a new thread. Still, overall throttle response is better, and I think even this change will improve any OHV 6.

Also, to get away from the heavy 3 finger pressure plate and the stress it places on the delicate suspended pedal configuration in the 8E trucks, the local clutch rebuilder matched up a diaphragm pressure plate for me. Others here reported that a 409 PP fit, but the bolt holes were just a bit off. What he found was an IH Scout 4 cylinder clutch matched perfectly, including finger height. The odd thing is that instead of 6 mounting bolts, it only uses 3 ?!?!?!? He felt the clamping pressure would be fine for the 6, and probably OK for stock V8's.

Tomorrow I'll get more 3/16 rod and make one more throttle linkage, then next weekend start building the new bottom end!

Ron Dame
'63 Champ

[Guest]

Ron, I remember on my 7E7 (thru-the-floor) clutch, the linkage had so worn out, I had to find a donor truck's parts. It was two feet on the clutch for shifting. No wonder the old stuff wore out! I asked the clutch rebuilder to go easy on the springs and it's a beautiful thing now. Not planning to tow stuff anyway.
Sounds like your project is coming along smartly!