View Full Version : Need tips for dial indicating Champ 6 bellhousing

07-02-2006, 05:44 PM
When I rebuilt my '48 M5, I wasn't too focused on the engine serial number. I later figured out that the engine had come from a '48 car but had been coupled to the original truck bellhousing. After two years of driving, I started to have some transmission problems and pulled things apart. The throw-out bearing was shot plus some internal transmission parts worn and the input shaft sleeve of the transmission scored. The clutch never did engage smoothly.

After a lot of struggling with a magnetic base and dial indicator, it looks like the bellhousing is off by about .025" or more towards the 10 o'clock direction. I now assume that no one dialed the housing in when the engine swap was done many, many years ago. Of course, the truck hadn't been driven in 18 years before I got it.

Anyone have suggestions about how to re-center the housing and redrill the dowel holes? The truck's in the garage but I don't have a lift. I can just sit up under the truck with the plate removed from the cab floor, but it's mean working under there.

Gary Ash
Dartmouth, MA
'48 M5
'65 Wagonaire Commander
'63 Wagonaire Standard

07-02-2006, 05:54 PM
I wouldn't wish dialing in a bellhousing in the car on my worst enemy. I am not saying it can't be done, but I can say that I wouldn't want to do it. I would also think it would be easier to just buy an engine hoist and fab a little stand for the engine rather than attempt to do it in the car.

I did make a little fixture to hold the dial indicator, it is just a piece of aluminum 'L' stock drilled to fit two of the crank bolts, and a 'C' channel screwed to it at a right angle, and finally, a clamp to hold the dial indicator is screwed to that. much easier than any other way I've seen, BUT, you have to remove the clutch to use it. Otherwise you pretty much have to have the factory tool.


55 Commander Starlight
62 Daytona hardtop

07-02-2006, 07:03 PM
Is there enough give in the bolt holes to move it .025?
Do you have over size dowels?

07-02-2006, 07:52 PM
garyash, I have a J-2025 tool if you need to borrow it. Just pay the freight both ways. E me if you want it.

07-02-2006, 09:06 PM
i fit a magnetic base for the dial indicator in on the crank. if you can picture dividing the bell housings into quarters with a cross. the vertical line running from 12 to 6 oclock, horizontal from 9 to 3. make marks and measure at these points. make sure the bell housing bolts are snug and tap it with a dead blow hammer until it measures out. it will move enough if you take out the dowel bolts. then once it is right take a drill with a 3/16 bit and drill a hole through the bell housing, plate and block, on each side of the motor. this works better if you dont have the right reamer for the dowel bolts. after you align the clutch and pressure plate, put the bell housing back on loose and drive 3/16 roll pins into the holes thus realigning it to you prior measurment. now your bell housing fits to your block no mater how many times you need to remove it. i did it alone on my car, i set up a mirror so i could see my marks on the bell housing and move the dial indicator to each one exact. i just wrote on the bell housing with a sharpie. if you need me to explain it better email me jim

07-02-2006, 09:34 PM
Gee, Klif, I hadn't thought about the idea that there might not be .025" slop in the rest of the bolt holes, but I guess I could always run a 3/8 drill through all of the holes. The two dowel bolts get put in holes reamed oversize to .390-.3905". Grizzly Tools has a set of 7 adjustable hand reamers for about $44, best bargain I found on line. A lot of places want that much for only a single reamer. On the other hand, I like Jim Wise's suggestion to just drill two new 3/16" holes and stuff a couple of roll pins in. I'm hoping I'll never need a complete set of adjustable hand reamers in the rest of my life, so why spend $44 at Grizzly? It;s the waiting that kills me, even more than the money.

I did take the clutch out. Even then, I could not get the magnetic base to sit on the flat part of the flywheel AND clear the bell housing. It kept bumping some spots on the inside of the housing. I finally took a 4" wide x 1/8 thick piece of steel and trimmed it to the diameter of the clutch housing, then drilled acouple of 3/8 holes in it. I put two of the clutch housing bolts through it so that I had a wide, flat surface for the magnetic base to clamp on to, right on the axis of the crankshaft. It's still impossible to get a normal dial indicator to be exactly perpendicular to the bore of the bell housing, but it's close enough to see if it's off center.

Gary Ash
Dartmouth, MA
'48 M5
'65 Wagonaire Commander
'63 Wagonaire Standard

07-02-2006, 10:59 PM

The bellhousing can be dial indicated in with the clutch installed, but you need to rig up something similar to the Kent-Moore tool used for clutch disc alignment and bellhousing alignment. Go here for pics showing this setup on my '63 Champ pickup: http://racingstudebakers.com/coppermine/thumbnails.php?album=76&page=5

Basically, the tool is such that the end that fits into the pilot bushing will expand and hold the tool. Then, a normal Starrett (other makes have similar setups) 'clamp' for an indicator holds the indicator to the tool. Look at the pics, these will show it better than I can explain it. Click the thumbnails to bring up the larger pic, and if you want the really big pic, click again.

I can take some closeups of the tool, if you decide to make a similar tool.

I hope this helps.......


Visit The Studebaker Skytop Registry website at: http://hometown.aol.com/r1skytop/myhomepage/index.html

07-02-2006, 11:04 PM
You may not have to be exactly perpendicular, because you dont care what the reading is. All you want is as little movement of the dial needle as you can get.

07-03-2006, 02:55 AM
quote:Originally posted by klifton1

You may not have to be exactly perpendicular, because you dont care what the reading is. All you want is as little movement of the dial needle as you can get.

I have "dial-indicated" a couple of Stude engines by a variant on the scheme described in some of Dick Datson's books. Clamp a straight used engine valve to the flywheel or crankshaft by using a metal strap with holes to fit two of the crankshaft bolts, and a large central hole to fit over the stem of the valve.

Now Dick went on to describe a means of centering this fixture, and then mounting a dial indicator on it, etc., etc. I just attach a tight-fitting metal block which bears a sheet-metal pointer. Pointer is attached to a pivot on the metal block with a small compression spring, so it can freely be moved, yet will stay put under only the force of gravity.

Set that pointer against the inside of the big central hole in the face of the bellhousing, and rotate the engine through one full turn. Best if you take out the spark plugs, and have a helper turn the engine from the front. Now that pointer tip will swing a circle that is exactly concentric with the axis of the crankshaft. Has to, that's geometry at work. If the crankshaft is NOT concentric with the bellhousing, the pointer will brush heavily against the hole on the "close" side, and miss it altogether on the "far" side. Find the two transition points where it goes from touch to miss, and from miss to touch, and mark them. The place to administer a hammer whack is midway between those marks on the "miss" side. (I assume you have already removed the dowels, and have the bolts snugged up enough that the bellhousing won't move on its own, but can be shifted by a hammer blow.)

So give it a whack, reset the pointer, and have your helper pull the engine through another revolution. Find the new "close" point, and see if it's shifted. The portion of arc marking the "miss" segment of the circle should gradually diminish as the bellhousing approaches perfect alignment. Eventually, you should reach a point where the pointer very lightly brushes the I.D. of the hole all the way around as the engine is rotated, or maybe hits and misses randomly through a rotation.

This method won't tell you how much misalignment exists, but it will serve to indicate when the misalignment is practically zero. If I remember right, the spec is .002", and the pointer method should beat that. And it can be done under the car; I did it on my Avanti, and no Studebaker is more cramped in that department.[}:)]

You have to have the spring tension holding the pointer on its pivot set just tightly enough to keep it from shifting under its own weight. Too tight, and it may spring back, rather than shift permanently as it it drags on the "close" side of the hole.

No reason you couldn't make a support for the pointer out of a clutch aligning tool, or anything else that could be attached to the clutch cover. (Maybe a metal disc with 3 rare-earth magnets to glom onto the release levers?) The object of the exercise is to make a temporary extension of the crankshaft to swing a pointer within the hole on the back of the bellhousing. When that pointer swings a circle that is imperceptibly different from the hole in the bellhousing, you can consider the bellhousing to be adequately aligned. You have probably reached the point where clearance on the rear main bearing is the limiting factor.

I hope this hasn't simply added confusion to the issue. I have used this method several times, and prefer it, despite posessing a dial indicator.

Gord Richmond, within Weasel range of the Alberta Badlands

07-03-2006, 10:28 PM
What is the procedure for automatics, since we are on this subject? What do you reference off of on the transmission?