Alfa Romeo Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
3,486 Posts
Discussion Starter #1
Put on new rotor, slid hub on spindle and tightened castle nut per spec. Then backed it out a tad to first castle notch for cotter
Pin. But rotor is still loose. Is this normal? I know once wheel is on and lug nuts tightened rotor should snug up, but just wanted to make sure disc is ok to be loose.

Thanks.
 

·
Administrator
Joined
·
17,066 Posts
No. The spindle nut only secures the hub to the spindle. There are 2 screws that hold the rotor to the hub until the wheel is installed & the lug nuts tightened. Those screws may not be strong enough to pull the rotor tightly onto the hub.

Try putting the wheel on, tighten the lug nuts then remove the wheel and tighten up the screws.
 

Attachments

·
Super Moderator
Joined
·
10,635 Posts
There are 2 screws that hold the rotor to the hub...
The first question we should ask: Do you have those screws? Because without them, yes, the rotor will be loose on the hub.

These are the screws labeled "1" on the diagram that ghnl posted above. They are slotted head and about 5mm in diameter.

If you don't have those four screws (2 per side) it isn't the end of the world. The lugnuts will hold the rotor in place. Replacement screws should be available at a hardware store - they're just flathead, metric screws. Maybe someone can post the diameter, pitch and length.
 

·
Premium Member
Joined
·
14,037 Posts
Sometimes you get lucky and one of the holes lines up well with the castellated nut but other times it can only set up the hub too loose or too tight. You can make shims from thin shim stock to go behind the castellated nut if this is your problem
 

·
Registered
Joined
·
3,486 Posts
Discussion Starter #5
Wow, you guys set me straight!! Thanks, Eric, Ed, and Jay!! Right, geez, I almost forgot about the two screws!! Yes, I do have them. I will screw them in first, then complete with wheels. What would I do without the buddies here.........
 

·
Registered
Joined
·
3,486 Posts
Discussion Starter #6
Sometimes you get lucky and one of the holes lines up well with the castellated nut but other times it can only set up the hub too loose or too tight. You can make shims from thin shim stock to go behind the castellated nut if this is your problem
Manual says to back out the castle nut 90 degrees or a quarter turn, to first notch. This is after torquing to spec. Agree, people?
 

·
But Mad North-Northwest
Joined
·
10,535 Posts
Manual says to back out the castle nut 90 degrees or a quarter turn, to first notch. This is after torquing to spec. Agree, people?
Yes.

As explained above, if you followed the procedure your hub is probably attached to the spindle fine, it's just the disc that's loose on the hub. You can fix that by either putting in the flathead screws, or bolting on the wheel.

The screws are just there to hold the disc to the hub during assembly/disassembly. Once the wheel is on the wheel lugs hold everything together and the screws don't do anything.
 

·
Registered
Joined
·
549 Posts
I will screw them in first, then complete with wheels. What would I do without the buddies here.........
coat those screws with anti-seize. Don't even bother installing them if you are not going to use it! Having had to drill out one of these lovely vintage flat head screws, I know how painful it can be.
 

·
Premium Member
Joined
·
14,037 Posts
Manual says to back out the castle nut 90 degrees or a quarter turn, to first notch. This is after torquing to spec. Agree, people?
No. Automobile design teams are multi-disciplinary. This solution makes the accountants smile and the engineers cringe. Taper roller bearings should have .001" to .007" end play. !/4 turn of the nut is .015". As a mechanic you can be like the accountant and say it is acceptable or you can be like the engineer and take a step in the direction of perfection.
http://www.timken.com/EN-US/solutions/automotive/aftermarket/lightduty/TechTips/Documents/Vol2Iss1_Proper_Tapered_Bearing_Settings_English.pdf
 

·
Administrator
Joined
·
17,066 Posts
Taper roller bearings should have .001" to .007" end play. 1/4 turn of the nut is .012".
Well, which is it? From your link to Timken's instructions:
To adjust the setting of this bearing:
Step 1: Tighten the nut while turning the hub. When there is
a slight bind on the bearing, the parts are seated correctly.
Step 2: Back the nut off 1/6 to 1/4 of a turn or sufficiently to
allow .001” to .007“ end play.
I suppose the "or" allows a lot of leeway?
 

·
Premium Member
Joined
·
14,037 Posts
I suppose the "or" allows a lot of leeway?
sadly Alfa's adjustment method is insufficiently precise to meet Timken's specification. If the thread was 1.00mm instead of 1.5mm and if there were three holes instead of two, then it would just meet spec.
 

·
Premium Member
Joined
·
14,037 Posts
alternative solution

One of my racer friends uses these. Tighten it until there is barely perceptible end float then stake it. I prefer the shim method.
 

Attachments

·
Registered
Joined
·
3,486 Posts
Discussion Starter #13
Well, I don't have shims and stuff, so will be happy doing it the way manual says. Car made it ok for 28 years with no race damage so far. I will set it for just a tad of play for the washer, as book says.

That old cotter pin seems too big though, I heard never use an old one so will buy new of course, but debating if I should get slightly smaller one. Had such a bad time sliding out the old one, not sure if it is normal. A new one will be very straight, so should solve my woes.

Big thanks, people.
 

·
Registered
Joined
·
3,486 Posts
Discussion Starter #14
Cotter pin will not go through the hole, it's super tight and binding, yet castle nut is tight. I tried removing some grease thinking I packed too much and retightened the castle nut but still the cotter pin will not go through.

Should I keep removing grease behind the bearing? Caliper is loose. What could it be?

Thanks!
 

·
Registered
Joined
·
3,486 Posts
Discussion Starter #15
Figured it out, the inner rubber seal on the hub has a circular spring that's all mangled and getting in the way of the hub seating right. What's the worst that could happen if I remove the mangled spring and put it back together without that spring? The rubber seal has no tears in it...
 

·
Registered
Joined
·
113 Posts
Just curious, is it mandatory to replace the bearings, when replacing the front disc rotors? I am planning to do the front rotors this spring. I seen bearings on eBay for less than $10, which seems a no brainer to swap out, unless these are cheap replacements. The Alfa dealers are more in the $40 range.
 

·
Administrator
Joined
·
17,066 Posts
is it mandatory to replace the bearings, when replacing the front disc rotors?
No. If the bearings are in good condition - races undamaged, rollers smooth - then washing out the old grease and re-packing with fresh grease is all that's needed.
 

·
Registered
Joined
·
3,486 Posts
Discussion Starter #20
sorry for delay, people- decided to have a shop pop out the old seal, then install. i'm back in FL now, but Jr will patch it all back up..........thanks for all the help as usual.
 
1 - 20 of 22 Posts
Top