Dial indicating a bellhousing

[Mighty]

Just wanted to get some opinions from people that have done this before…..I’m in the process of putting a Richmond super t10 plus in place of the factory saginaw in my wagon and this is my first attempt at something like this. When we slid the transmission in to get the driveshaft measurement it was a little too snug in my brothers opinion so he said we better check it. My new flywheel checked out, the new clutch is removed and one of the flywheel bolts is out and the dial indicator is stuck on. We just picked the 6 o’clock position to be where we zeroed the dial. Made a couple revolutions and ended back at zero. As you can see by my drawings and a red mark on the bellhousing it’s about -.015. Nothing more than +/- .005 is acceptable from what I understand. So we zeroed the dial in that location and all the measurements basically flipped. Divided that by 2 so am I correct in saying that I should need a .0075 offset dowel pin? And the bellhousing needs to be raised up that much since the low spot is at the top of the hole? Also, the measurements at the 3 and 9 o clock positions are within +/- .005 from each other but will they fall within spec with the dowel pins that I assume I need shifting it the .007 in the up direction? The bellhousing is torqued to 45 ft lbs and I tried to make sure the dust cover at the bottom wasn’t causing it to be crooked at all. I cleaned the bellhousing and used to emery cloth on all the rough spots. It’s the factory 45 year old bellhousing though so I’d imagine it’s out of round. I just wanted to make sure I’m not way off on my attempt before I purchase new dowel pins. Thanks for any input

 

[Bonnewagon]

I have never done this, but I tend to stick to the sloppy Saginaws. This video is pretty informative.

 

[Mighty]

That’s one of the videos I watched. I think I’m just going to order the .007 offset dowels and see what happens.

 

[Bonnewagon]

it was a little too snug

Any chance it was the pilot bearing? I only use the #7109 roller type and I once measured the clearance between the input shaft and pilot baring. It as .001", so even a spec of crud will cause interference. My buddy could not get his Tremec to go in. He used the oil-impregnated bronze pilot and it was just a hair out-of-round. He switched to the roller and it went right in.

 

[Mighty]

I don’t believe so. I have the magnetic indicator stuck to the flywheel so the pilot bearing isn’t really part of the equation. When my dad put the car together he used a roller pilot bearing but I’ve since replaced it with the one that came with my McLeod clutch. It’s gotta just be the stock 45 year old bellhousing is slightly out of round. I bet when my brother and I were little and “helping” my dad we probably dropped it or kicked it or who knows what’s. Plus I’ve read that heat cycles from normal use can cause it to start to go out of round. I posted pictures some where on here of the original flywheel and it had some heat spots on it so I just bought a new one and a new clutch that i didn’t plan on originally

 

[Rt Jam]

The .007 is a great start. The aim is 0.000 but if using the smallest offset gets it closer, you're done.

After you insert the trans/input shaft. Press the clutch pedal. One you press clutch pedal and release, this will be the best disc centering.

 

[Mighty]

Unfortunately the body of the car is up on a rack and everything clutch related is in pieces at the moment lol. I’m going to pick up the offset dowels tomorrow and see what happens.