Bearing tightness in the knuckle of a '71 Eldorado

[The Tassie Devil(le)]

G'day all,

Would appreciate it if anyone can advise me of the required "tightness" of the outer cups of the bearings inside the knuckle of a '71 Eldorado.

I removed the bearings from the knuckle of a '71, and the cups were both slightly loose, and I found out that the outer grease seal had been turning, and wore an excessive groove in the knuckle.

This had rendered thew knuckle useless, and luckily I have a replacement.   But, the bearings are still a slip fit inside the "new" knuckle.

If this clearance is supposed to be there, can I use Loctite Bearing Retaining Compound to take up the "slack"?

Notice in the pictures, the worn seal, knuckle, and where some previous person used the centre-punch method of tightening up the inner hole for the bearing cups.   Plus, the seal is so worn that it slips down into the hole.

Thanks,

Bruce.

[TJ Hopland]

I think the loctite only works with a specific clearance.  Its got to be exactly 2 molecules gap or something like that.   IF its less it won't work because the stuff won't fit in the gap and if its too wide they don't wedge themselves in properly.    I'm sure its more complex than that but that is how a old time machinist explained it to me.  You can't just use it to fill in a random tapper or gap on a critical application.   

The other problem you will have in a case like this is alignment.  IF your bore isn't straight and round the races may not be held straight and square.   I wonder if maybe the inners not being pressed onto the hub properly maybe causes the outter races to try and walk around and eventually wear?   I used to work on some equipment that had a similar but different arrangement.  On those you really had to follow the torque sequence and stages carefully or you would be back real soon with a whole assembly rather than some new seals.  IF you just threw it together you would end up with the bearing supports not aligned and the shaft would actually flex and stress everything.   It felt nice and smooth with no binding and proper lash but I learned the hard way one time that wasn't good enough.

Manuals all talk about having to use special tools and presses to install and remove these bearings so its officially supposed to be a press fit.   Until recently all the cars I have encountered have been tight.   I kinda tried to change a set of bearing myself one time and it didn't seem like it was going to happen without making or getting the tools so I just took it to a drive line shop.   

I say recently because I was changing a CV axle this summer on my 'good' 73.  I don't remember what or why I was pounding on something in the general area and I noticed the hub slid slightly out of the knuckle.   I could not get it back just pressing with bare hands but it didn't take much of a tap back in so I'm not quite sure what is going on there.   I'm assuming that before too long I will be looking for a replacement knuckle and bearing for that side.    Those bearings were installed by a tire shop 20+ years ago when I first got the car.  I only used them that one time.  It would not surprise me to find out they did something improperly to make it easier on themselves like hone out the knuckle. 

Slightly newer than these they went to the outer race either being held by a retaining flange or in some cases the race appears to have ears on it that bolts to the knuckle.   My guess is they did this because the press fit into the knuckle that didn't get changed was easy to screw up.   

["Cadillac Kid" Greg Surfas 15364]

G'day Bruce,
As I am sure you know by now, the shop manual does not directly talk about the bearing race, but if you note on installation the bearing "package" is fully installed "when the race is seated in the hub".  That said if t'wer me I would consider any hand installation looseness to be excessive.  Lucky you have a spare (or two).  That's one of the things I bought for my Eldo, a complete drive train and suspension.  Glad I bought it because I never needed it.  If you make it to the GN here in Texas next year I'll make you a deal on it. Only about 600 pounds of iron. Probably have to buy the ship to get it home. Ha.
Greg Surfas

[The Tassie Devil(le)]

G'day Greg,

When I purchased my '72 in 2007, I also purchased a rusted-out 71 with the idea to remove the convertible-specific parts, and ship them home with my '72, in 2008 but as I managed to upgrade to a 40 foot container, I brought home everything except the rusted remains of the body, less everything removeable, and still got $175.00 for the scrap.

I came home with 2 tons of very valuable pieces, and boy, have they come in handy, not only for me, but my friend with the '71 I have been working on.

Bruce.