TT,

The early ones I worked on did not have them. the 70's vette did have them. what is the date code on yours? I wonder if this might have been a supplier issue?

 

I'll have to check, I tried to find a pic of them that shows the date code but am having trouble finding it, I'm about 100% certain they are the original ones, the stock bearings were still in there w/ the stock inner seal out of 2 pieces stamped metal w/ folded flaps and the rubber seal wedged between them..you know the ones I mean They also have the flattened undersides. I've done the bearings on a couple of other cars and they all had the style with no well, the cars were all late C3s (77 up)

 

Interesting, I'd like to know for sure now. That's what I found in doing them,maybe Tom 454, John Z, or one of the others would know the deal for sure? Joe Lucia would probably know but I don't think he shows up here anymore. I found a lot of them with mixed up codes and considering dealers would wreck just about every part doing a rear bearing job it's not unusual to find all kinds of things. Another example are the strut rods, the small head vs the large head. I find a lot of these mixed in with the supports. The lg head came out in '75 and as a service part.
Gary

 

My 76 has the well. I think they are origional but couldnt swear to it.

 

I can't imagine what you were doing when you discovered this

 

Gary, I ran into this same situation when doing my 74......2 different styles. One side had obviously (to me) been worked on at some time in the past. It was straight through....no well. The 2nd side had never been apart from what I could tell. It did have the well and I feel pretty certain was original. I always assumed the side without the well was a later model since it was repaired (probably replaced?) past 1974. I never even thought to look for date codes....wish I had.

 

will the later models fit the early cars? I have a set off of my 81 that are in better shape than the ones on my 71

 

I never had a problem removing or installing the races. There are notches in the casting so I use a long brass drift while the support is in a vise and easily drive them out.


The 75+ rods with larger heads were the service part for years. They fit the early supports for the most part. Year ago Brian Bair informed me there is a potential of binding in extreme travel at the legs. I check this when I have rods on with T arms to see if there is any binding problem. A die grinder will solve it without any issue. I use a Bridgeport and mill in a small radius to resolve this.

 

I know but running the tig torch around it is so much easier and faster than hammering them out, it's just an old trick.

 

My understanding & experience indicates that there was one major design change regarding the well/ears.

I believe it is NCRS documented. Ferget which year.

TA's and spindle supports are replaced regularly... can't make a judgement call by appearance. Who knows which ones are original or not. I have both kinds laying around... C2 & C3 vintage.

Carbon 14 dating.

It's all the rage.

 

Now I think you got something there!LOL

 

Hello!
I just found this site. I have owned my '78 since 1992. I have done the rear bearings myself all ready. Made my own clearance checking tool out of a large bolt. I forget what size it was. It was pretty close, in diameter however to the holes in the bearings. Just turned it down a little in the lathe for a snug slip fit. I assemble the bearing set with spacers, put extra washer on the outside so I catch threads on the bolt (shoulder on the bolt has to be long enough to go through both bearings) and torque it to 100 lbs. I too surface grind my spacers to the correct size. I didn't go to .0015", I set mine to .003". The specs I read put that in the middle. That is why it is so valuable to have a site like this. Next time I will set them to the low end.
My question comes in with setting the runout on the brake rotors. I did my bearings one side at a time. Started with the left side. The spindle was bent quite badly, around .050" as I recall. I ordered a used one from a salvage yard which they guaranteed me would be good. It came in with about .010" of run out. I called them and they told me that was great, a new one wouldn't be that good. I had never done this before, so I took their word for it. I assembled new rotors to the spindle, torqued them down to 80 ft/lbs and witness marked the rotor to the spindle. Then took the spindle/rotor assembly to a machine shop and had them turn the rotor true to the spindle to eliminate run out. I had them use the factory centers machined in the spindle. That really took quite a bit of meat off my new rotor! But, that was all I could think of to fix it. The magical thing that opened my eyes was when I did the other side, the spindle had no run out. Better than a new one my butt. However I still turned the rotor to the spindle anyway. Didn't take much and I am very satisfied how that side turned out. I will have to rework the left side one of these days with a new spindle this time. Is there a better way to set the rotor run out than turning them as a set on a lathe?
Sorry for the long letter
Curt

 

I've setup rotors and spindles in a lathe and machined them. Problem is once you break them apart you're going to loose your dial in. Maybe not by much but you'll lose some. You'll have to assemble the rotor/spindle as one to do it that way and maintain the turned dimension. I rather set the runout afterwards with a bolt on rotor and SS shims and lock them in once I get it to .002" or under.
Keep in mind too the new rotor thickness is 1.250 and the throw away dimension is only 1.215 just .035" for both sides to machine so I would check your rotors to see where they are now. No runout with undersize rotors isn't any better then good rotors and runout.

 

I found the same thing on both of my old spindles this weekend, must be something in the water...
Vic

 

so I assume if this is backwards the cup part of the metal faces the bearing, my seals are square cut, see this thread
http://forums.corvetteforum.com/show...post1553765054

 

Sounds like you have the National type of seal with the flat square rubber. I don't like or use them. I've found some that failed. I use the angled seal,which NAPA carries. The cupped face goes in on yours, the flat face is the exterior surface.

Gary

 

I just finished up a set of arms for a forum friend and had a couple of bad bearing sets. First time I had a problem with all the Timkens used but I guess that happens. I couldn't hold endplay tolerence and ended up buying a set from another source. I finished the job and held endplay to .0015-.002 and was satisfied with the outcome. Just want to pass along the info in case anyone has a similare problem. I had this happen once before with another brand but not Timken. I was in contact with the factory too and they were very helpful but didn't have an answer. I returned them for credit, btw.

 

Just had the same problem with my Timkens. Replaced with a new set of Timken bearings and other than my endplay getting slightly tighter my problem went away. Did you return them to the factory or parts store ?

When I use a setup tool, I torque the nut to 100LBS and read the endplay. Lets say I get .0015" . When I go and press the bearings onto the spindle for reassembly of the trailing arm and torque the nut to 100lbs, the nut does not line up with the hole for the cotter pin. So, I tighten up the Castle nut until I get enough clearance to insert the cotter pin. Doesn't that increased tightness affect the endplay and how do you account for that?

Carl

 

Carl, Very interesting you had the same problem? I know the tech at Timkin I spoke with has this post on his computer so maybe there's more to this then I suspected? Where are you located, my bearings came from the Precision Industries wharehouse in NB to CT.
Also did you face off the large spacer on a surface grinder? These can be out several thousands and cause problems as well. The last arm I did not only did I parallel grind the shim and spacer I alos radius the ID as I found it was hanging on a burr and might have been hanging on the spindle. The last bearing sets had 2 different problem using the same races. 1 set lost the endplay by .004" the other started to bind at .002" in the setup tool.
You can torque past the 100 ft/lbs to align the cotter pin, most everytime you'll have to. If you think it's too much then you can face the nut that sits against the washer. Also use a new washer and nut in every rebuild. Lastly check the job when you are done. I had to torque past the 100 ft/lb mark to align the key but the spindle ran smooth when I re-checked it.

 

I live in Michigan and got the bearings from AutoZone (both sets)
I did not use a surface grinder to resurface the large spacer, instead I wet sanded (250 grit) it on a flat surface, in a figure 8 motion to take off the burrs. I am still having a hard time finding a local machine shop that takes small jobs, so I have to resort to sand paper sometimes.
My other trailing arm I did, I had to go past the 100ft/lb mark to align the key. I had to go tighter by almost 3/4 of one of those post (not sure the technical name -I'm a electronic guy) on the castle nut. I lost almost all my .0018 endplay, but I am not sure if it was during my pressing (using 20 ton press) procedure, increase torque or the grease. It still ran smooth, so I'm left it alone and will run it that way. From your post, it looks like you keep to you guns and shoot for .0015 - .002. Next time I think I'll shave the nut if I have to tighten it that much.

Thanks
Carl