rear end question

[reborn55]

Tore rear end apart last night--going to replace pinion bearings. Noticed that the bearing closest to the pinion was not pressed down flush against the spacer and gear. Any ideas as to what may have caused this. I don't know if and when this rear end has ever had any work done to it besides myself doing it. Hopefully this will help raise the car from hell to the car from purgatory.Also does anyone have a spare 8.5 pinion yoke that would like to get rid of. Thanks

[wayne petty]

i have not torn into many rear ends...  but the ones i have usually have a thin washer behind the large bearing on the pinion gear... this washer gives you adjustability..   when setting up the rear end..  

most bearings are really really close..  and if you have one of the same brand...   you hone out the inside bore just enough to make it a slip fit.. instead of a press fit..  you also do the small bearing...   this allows you to install the pinion gear and with a tapped out nut.. bring it up to proper turning torque.. so you can set the pinion depth..  by assembling and measuring it..   if you have a press fit bearing.. you can damage the bearings and the pinion gear pressing them off and on to change the shim washer..   once you get the pinion right..    you can take it apart...

press on the press fit bearing.. put a new crush collar in...  and set the turning torque.. i just don't know.. if you should put the seal in and test the turning torque with an INCH POUND dial type torque wrench..

i am sure there are others who do rear ends more often.. and will correct me on lots of points i have slightly bent here..    i also like BIG CHUNKS of strong magnets wedged in to a corner...

and... i am all for taking a rear end totally apart after welding the mounts on...   running a ball hone on a long shaft through the axle tubes.. to get rid of any welding scale that shows up inside.. then washing them out  with a toilet brush on a piece of pipe..    a 360 degree small sprinkler head on the end of a piece of pipe... could also be used to wash out the axle tubes..  while you are brushing them out..

yes i am bent about getting stuff clean..

[enjenjo]

As Wayne said, there may be a shim between the rear bearing and the head of the pinion.  What are you doing? Ratio change?

[reborn55]

Still fighting noise in the rear end.  Decided to replace pinion bearings and if that doesn't do it--will just live with it til next year.  I know there is a shim in between the gear and bearing--the thing is that there is too much of a gap there.  You can see the shim flop around.  Had new bearing with old shim pressed on--machine shop found no burrs or any reason why there was such a gap there.  Putting together in the next few nights and we shall see. Thanks

[enjenjo]

Still fighting noise in the rear end.  Decided to replace pinion bearings and if that doesn't do it--will just live with it til next year.  I know there is a shim in between the gear and bearing--the thing is that there is too much of a gap there.  You can see the shim flop around.  Had new bearing with old shim pressed on--machine shop found no burrs or any reason why there was such a gap there.  Putting together in the next few nights and we shall see. Thanks

Ok. If that is the case, for some reason the pinion moved back. Possible, but not common. I have seen one a few years ago in a Pontiac. I hate to say this, but I think it will still be noisy with new bearings.

[reborn55]

you are probably right--but at least I know it won't be bearings--they are all NEW.  Just getting tired of fighting it.  Drive it to Bowling
Green and come home and take a break for awhile and then tackle it later on some time.  Either that or let some one else tackle it.

[GPster]

I read all these posts, especially for the answers that Wayne or Frank post in the hopes of learning something. Are you sure the bearing is right? Maybe it's a "cross-over"? Maybe there is a different camphor (best quess of 3 on spell check) on the pinion than the bearing. I know there can be that problem between inner wheel bearings and spindles, maybe here too. How does the wear pattern look on the ring gear? If the pinion is too far in won't that show up as an un-centered pattern on the ring gear? GPster

[tomslik]

I read all these posts, especially for the answers that Wayne or Frank post in the hopes of learning something. Are you sure the bearing is right? Maybe it's a "cross-over"? Maybe there is a different camphor (best quess of 3 on spell check) on the pinion than the bearing. I know there can be that problem between inner wheel bearings and spindles, maybe here too. How does the wear pattern look on the ring gear? If the pinion is too far in won't that show up as an un-centered pattern on the ring gear? GPster

it'll most likely show up as a gear howl, aside from the wear pattern....

http://www.richmondgear.com/01form.html

i ain't a huge fan of their gears but the instructions are good....

[reborn55]

Guys were all right..Noise is still there.  Sometime in the next 6 months I will probably put a new ring and pinion in or find another rear end.  Got one last week, but when I pulled the cover--got more water than grease.  It was free--got one more to get next week--also free.  As usual--THANKS

[wayne petty]

if there is a space between the back of the bearing and the pinion gear... other than the tiny gap around the washer... the pinion will be too deep into the ring gear...

the mis matched chamfer radius...   ( i had to google it my self..)

>)    is not going to fit..
))  will fit

>> will fit..

)> will fit..

the first part being the bearing back were it turns into the bore... the second is the pinion gear.. where  the bearing seats...

got any number off the bearings you bought?   rear end application..   12 bolt.. 9"  so i can do some research in my bearing catalogs...  so you can be prepped for next time....    also what gear ratio might help and if it is a factory set of gears... or not..

always glad to help....

if you had mentioned that the shim could wiggle around in there with the bearing pressed all the way on.. you would have gotten a totally different answer from me...   or even posted a picture...

i can always mail you the 17 pound sledge hammer..  but i want it back...


knowing what's wrong...  i don't think i would put a lot of miles on it.. as you may put wear on the ring and pinion teeth that will prevent you from getting the rear end quiet...

so post the info... i will work on info for you... if you changed the bearings... grab the numbers off the inner races... take a photo if you can..

edit... found the info..

Nova 10 bolt--73-74 vintage

[reborn55]

Noise late last year.  First thought it was axle bearings(had the sound of bearing whirring noise.)--they were bad--replaced them, noise still there, replaced side gears, side bearings and then the pinion bearings.  The ring fear has a bunch of pitting on them like they had sat in water for awhile.  It doesn't sound like a gear whine as it is not constant whine.  Can finally hear it under the car by loading one of the brake cables.  feel the noise through  the leaf springs.  I am at a loss right now--just getting frustrated.  
There was a gap between the bearing and pinion gear.  When pressed on the machine shop fit it snug.  
Rear end is 72 Nova, 8.5, 10 bolt---2:73 ratio.
Going to Good Guys Bowling Green on the 16th--been making noise for the last 1000 miles or so than I can remember.  Sometimes with a ragtop the wind noise drowns out a bunch of things.  Get real noisy around 60-65 mph--seems to go away after that
Thanks

[wayne petty]

CHEVROLET - REAR DRIVE - Chevy II, Nova
REAR AXLE
P i n i o n


1979-1976 7.5" ring gear
Cone/Cup (inner) ............................HM89449-HM89410
Seal (outer) .............................................................8610
Cone/Cup (outer) .................................M86649-M86610


1979-1976 8.5" ring gear
Cone/Cup (inner) ............................. M802048-M802011
Seal (outer) .............................................................2043
Cone/Cup (outer) .................................M88048-M88010




1975-1973
Cone/Cup (inner) .............................M802048-M802011
Seal (outer) .............................................................2043
Cone/Cup (outer) .................................M88048-M88010

M802048  bore 1.625, width 1.010, radius 0.14


1972-1964 10-bolt housing cover
Cone/Cup (inner) ............................HM89449-HM89410
Seal (outer) .......................................................... 8611N
Cone/Cup (outer) .................................M86649-M86610

HM89410  bore 1.438, width 1.125, radius 0.14



1972-1964 12-bolt housing cover
Cone/Cup (inner) ............................. M802048-M802011
Seal (outer) .......................................................... 8460N
Cone/Cup (outer) .................................M88048-M88010


1963-1962
Cone/Cup (inner) ............................HM88649-HM88610
Seal (outer) .......................................................... 8611N
Cone/Cup (outer) .................................M86649-M86610


looks like too much difference to have the wrong bearing...   but does it have the right chamfer?    

need bearing cone numbers from the old bearing ... hope you still have it..  the larger of the 2...   the inner part...

[reborn55]

CHEVROLET - REAR DRIVE - Chevy II, Nova
REAR AXLE
P i n i o n


1979-1976 7.5" ring gear
Cone/Cup (inner) ............................HM89449-HM89410
Seal (outer) .............................................................8610
Cone/Cup (outer) .................................M86649-M86610


1979-1976 8.5" ring gear
Cone/Cup (inner) ............................. M802048-M802011
Seal (outer) .............................................................2043
Cone/Cup (outer) .................................M88048-M88010




1975-1973
Cone/Cup (inner) .............................M802048-M802011
Seal (outer) .............................................................2043
Cone/Cup (outer) .................................M88048-M88010

M802048  bore 1.625, width 1.010, radius 0.14


1972-1964 10-bolt housing cover
Cone/Cup (inner) ............................HM89449-HM89410
Seal (outer) .......................................................... 8611N
Cone/Cup (outer) .................................M86649-M86610

HM89410  bore 1.438, width 1.125, radius 0.14



1972-1964 12-bolt housing cover
Cone/Cup (inner) ............................. M802048-M802011
Seal (outer) .......................................................... 8460N
Cone/Cup (outer) .................................M88048-M88010


1963-1962
Cone/Cup (inner) ............................HM88649-HM88610
Seal (outer) .......................................................... 8611N
Cone/Cup (outer) .................................M86649-M86610


looks like too much difference to have the wrong bearing...   but does it have the right chamfer?    

need bearing cone numbers from the old bearing ... hope you still have it..  the larger of the 2...   the inner part...

Bearing numbers for the 8.5 are exactly the same as the ones you have listed  on the bearing and new part numbers.
thanks

[wayne petty]

ok....  now the question...  what did you use to push the inner bearing onto the pinion gear...    

i have used the old bearing with the cage cut and the rollers off after honing out the inside to make it a slip fit in my 20 ton hydraulic press..  to drive the inner race all the way on with the inverted old inner...     this lets you press just  on the inner race... not on the cage..  not on the rollers which would leave little dents in the race and flat spots in the rollers..

 if you have a piece of steel pipe.. that is a tight fit .. and will not hit the cage....  if the cage gets bent.. the bearing will really need to be changed again..

it is impossible to tighten the pinion nut tight enough to force the inner  bearing all the way on without ruining the bearings and races...  it has to be installed on the pinion gear with a press or a BFH..

one last thing... is there any score marks on the shaft where prior attempts have left ridges on the shaft..   these metal curls will stop the bearing from being driven all the way in...

most shops heat the bearing and drop it on using welding gloves then drive it home instantly with a driver tool or another modified bearing race..

wayne .. out...

[reborn55]

Wayne--had a machine shop press new bearing all the way on.  No scored marks or imperfection on pinion.
Thanks