Hello, new guy here (really old retired guy) 1st post.

This is kind-of a build along & question along thread. I have never done this (successfully) before.

I'm setting up 1972 Chevy passenger 12 bolt rear-end, (8.875" ring & pinion).

I picked up "pumpkin" at a bone yard & cleaned it out completely, looks good.

all other parts are new.

I have a Richmond 456 ring & pinion, Moroso Posi, Strange axles that are C-clip eliminator type, Timken bearings.

I welded the tubes into the center section & cut off the tubes just past the 4 bolt flanges, this is required for the Strange axles. Tapped the 1/8" NPT vent hole & Re-cleaned everything.

I'm trying to setup the pinion depth to 2.791" Richmond calls it the "checking distance" (this is the distance between the flat circle of pinion head to the centerline of the carrier bearings)
Also setting the pinion new bearing pre-load (25-30 inch-pounds)

The large pinion bearing inner race was a very tight fit to the pinion shaft, so (not being the sharpest knife in the drawer) I greased the race & shaft, put in a .025" shim between the pinion head & the inner bearing race & pounded it on with a brass drift, avoiding any contact with the bearings. (I have no press) Then heated up pinion shaft with a torch & re-pounded the race to make sure it was on all the way, (it's in & it's stuck).

Later when dealing with the small pinion bearing inner race, I found that I could easily reduce the pinion shaft by putting pinion in my bench vice & "shoe-shine" it with a 1" wide x 18" long strip of emory cloth stuff that I use for cleaning copper pipes, 1 minute tops. (I wish I had thought of this before I beat the large bearing on)

I got a Ratech pinion depth setting tool,
http://store.summitracing.com/partd...15&autoview=sku

Has anyone else used this? I hope it will be accurate.

Now I'm waiting on a depth micrometer from Amazon to put through the hole in the above tool to measure down to where the carrier bearing outer race will sit.

I also bought a Ratech solid spacer kit 1901,
http://store.summitracing.com/partd...15&autoview=sku

This takes the place of the normal crush sleeve & 6' breaker bar method (GM's revenge, oops I went too far method, he he).

This solid spacer & shims are used to set the distance between the pinion large & small bearings, which sets the pinion bearing pre-load (new 25-30 inch-pounds)

This kit provided shims that go between the "pumpkin" housing and the large pinion bearing race. I can easily, (with a brass drift), beat the large pinion race out of the housing from the front end as there are reliefs machined in the housing for this purpose.

Has anyone else used this kit or put shims between the housing & the large bearing race?

To be continued:

BBP

Sounds like you are going about it correctly so far. Since you didn't have anything to go by as far as pinion shims to begin with, I always started with .030 shims to begin with on the new bearings. This should get you in the ball park, as you have already done. The RATECH pinion depth setting tool is VERY good. I have never had to use the shims between the housing and bearing race but haven't built as many rears as some that will chime in. Also, I always use a standard{non locking} nut on the pinion yoke until every thing is how I want it and then use the supplied lock nut upon final assy. As you probably know, those lock nuts are a " single-shot" deal. Sounds like you have done your homework.

Unfortunately, you should consider the bearings you have been hammering on ruined. Always use a press to install a bearing because hammering will damage them. All is not lost though, you can make yourself a nifty set of test bearings by honing or boring them out until they are a slip fit on the pinion shaft. Then they will be easy to assemble and disassemble to set your pinion depth. Once you get it right, re-install it with a new set of bearings and verify that the pinion depth is still correct.

Sanding your pinion shaft is a REALLY bad and possibly fatal (for the gears) idea. Those bearings are meant to be a press fit to keep them from getting loose as they heat up, not to mention the fact that the surface you sanded on is precision ground to be concentric with the pinion gear. A wobble there is not going to be a plus for gear life. You can get a press that will install those bearings properly for about the price of a new set of gears.

Tom

As stated, I would replace that bearing and press on a new one. Also, sanding the pinion was a bad idea.

And the 1901 kit only comes with shims for pinion depth, it does not come with a solid spacer to replace the crush sleeve.

If you haven't ordered the pinion depth setting tool yet, don't. Instead, use a straight edge across the diff cover mounting surface and use a dial caliper to measure from the straight edge down to the pinion. Then measure from the straight edge to the machined carrier bearing surface. Subtract the smaller number from the larger and that is your pinion depth.

I have seen the machined surface of the carrier centerline{ cap to housing line} off center by as much as .020 thousands. Not a good way to measure for pinion depth.

do not do anymore sanding on the pinion gear. use a press from now on to do any bearing work. do not use heat on the shafts either. find someone who has a press. i have not used the solid sleeve like you describe. i use the richmond version. it has thin shims at the sleeve.
so far the housing prep sounds good. take your time and ask questions. post pics if you can. start with a .032 pinion shim. i do not ever measure the pinion depth. also start with .243 carrier shims on both sides. tom

The Ratech 1901 kit includes a 4222 solid spacer which is approximately .030" longer than their 4101 solid spacer. The 4222 solid spacer is also a replacement for a crush collar. It is suppose to be used along with the 1134 3.25" shims (also in the 1901 kit) that go between the housing and the large pinion bearing race.

It seems to me that shims, in either or both places, can be used to set the pinion depth.

I may have heated the pinion shaft up to 180* & maybe removed .001" in the area of the small bearing race, pretty darn evenly all the way around, just some of the black surface. I don't think that I ruined it (I hope). I will find out down the road.

My brass drift never touched the the large pinion bearings, only the inner race. I'm sure that I didn't damage it. I also used the brass drift to pound in the outer pinion bearing races into the housing, taking care to start them out & keep them straight.

On rianbechtold's idea of using a straight edge across the cover surface & measuring down, I wonder if that surface is machined perfectly parallel to the center line of the carrier bearings? I've never read about that being used.

I'm in the process on another site of trying to convince a guy that the carrier bearing cap parting surface can't be used as the center line of the bearings.

Thanks for the input, still waiting on my depth micrometer.
BBP

I'm in the process on another site of trying to convince a guy that the carrier bearing cap parting surface can't be used as the center line of the bearings.

This is exactly what I was refering to in my last post.

My brass drift never touched the the large pinion bearings, only the inner race. I'm sure that I didn't damage it. I also used the brass drift to pound in the outer pinion bearing races into the housing, taking care to start them out & keep them straight.



You don't need to touch them, it's shock of the rollers hitting the inner race that does the damage. Bearings are cheap. It's better to replace them now rather than have them fail later and have to do it all over again.

It is acceptable to install the outer races with a brass drift, just not the bearings themselves.

Tom

Yea, the shock of the impact is what hurts the bearing. Plus, I would be willing to bet the bearing is full of brass particles from the drift.

I have heard of the cap surface being machined off center and this always interests me. When I first heard it setting up my own, I did not measure from it. I have since talked to a few shops that all they do is rear ends and transmissions and they say otherwise. So I have set up four different rears since they told me to measure the way I have suggested and EVERY time it has been dead on (except the one that I used a richmond R&P but I returned the richmond and got a motive gear and it was perfect). I'm just suggesting to try it because I didn't believe it at first but believe me, when your first attempt for a pattern is DEAD ON four times in a row on four different rear ends, you begin to believe.

Also, if the cap surface was offcenter, wouldn't the housing or the cap dig into the bearing race since they are an interference fit?

I'm in the process on another site of trying to convince a guy that the carrier bearing cap parting surface can't be used as the center line of the bearings.


Btw, where does that depth setting tool of yours bolt up?

rianbechtold,

Click on the 1st link in my 1st post for a picture of the tool. I have several references by guys who use it & like it. It does not bolt on, you firmly press it flush on the head of the pinion gear, there is a nylon centering button. The end of it goes over against the carrier bearing race perch to set rotational position & then you put a depth micrometer straight down through the 1/4" hole & measure to the bottom center of the bearing race perch. Then subtract result from the number stamped on the tool. My Richmond gear set has a "checking distance" = 2.791"

Your post: "use a straight edge across the diff cover mounting surface"

& then you talk about using the carrier bearing parting surface being dead on, which surface are you sure of?

Carry your logic over to rod caps. They are not all the same (1/2 on each side of the parting line), if they were we could swap them between rods.


The bearings roll smoothly with no hint of damage & I don't believe that they are.

BBP