Brake conversion question

[BoatMan]

66 300 brake conversion under way. Spindles and donor parts are from a 69 Polara. Ordered bearings and rotors (1 piece) from local parts stores.

When putting the rotor on I have play. Seems like the spacing from bearing to bearing is too narrow causing the rotor to go back and forth ( maybe one sixteenth of an inch)

Races were already installed on rotors. However it seems like they could be further pressed in. On the rear you can see almost a quarter inch more that the ring could go down- same in the front.

Does anyone know how far in the bearings should be? What am I missing?

 

[BoatMan]

Here are some more images-

 

[Big_John]

Pardon my terminology... The part that came with the bearings- rings with beveled inside- were already installed on rotors. However it seems like they could be further pressed in. On the rear you can see almost a quarter inch more that the ring could go down.

Those are called "races". They press against the shoulder inside the hub.

That pic looks like it is in correctly.

But again, like in your other thread, I will ask this question... Are all the pieces there? Inner and outer bearings and races? Thick keyed washer under the nut?

 

[BoatMan]

Those are called "races". They press against the shoulder inside the hub.

That pic looks like it is in correctly.

But again, like in your other thread, I will ask this question... Are all the pieces there? Inner and outer bearings and races? Thick keyed washer under the nut?

Just posted some more images- as far as I know all the pieces are there-

 

[dmac01]

yes the race is "pressed" on to the hub and should be completely seated against the hub...I used a socket and hammer to gently tap the race into place. there should be no "space" between the inside of the race and the hub. Not hard to do just go slowly.

 

[Davea Lux]

Looks to me like you might have the '72 and later bearings. take the inner bearing and put it on the spindle, when it is all the way back it should fit tightly. If the bearing is loose on the shaft, you have the wrong bearings. Another issue when doing the conversion is that you must use rotors from 68-71 to fit the '69 spindle. The later rotors will not fit unless you use a '72 and later spindle.

Dave

 

[Yatzee]

66 300 brake conversion under way. Spindles and donor parts are from a 69 Polara. Ordered bearings and rotors (1 piece) from local parts stores.

When putting the rotor on I have play. Seems like the spacing from bearing to bearing is too narrow causing the rotor to go back and forth ( maybe one sixteenth of an inch)

Races were already installed on rotors. However it seems like they could be further pressed in. On the rear you can see almost a quarter inch more that the ring could go down- same in the front.

Does anyone know how far in the bearings should be? What am I missing?

View attachment 172911

If you had bought a conversion kit from SSBC there would be a spacer in the kit that slides on the spindle before mounting the router. This moves the rotor out slightly and creates the effect of the spindle being a slight bit shorter when you tighten the spindle nut. You need to have a spacer on the spindle but the issue is that the base of the spindle is machined with a 3/32 radius. You'll have to make the spacer so it sits tight against the spindle base where the seal rides when assembled. I'd get a machine shop to make the spacer from round stock and have the matching radius machined into the I.D. If you're really brave grind the radius off the spindle and use a thick flat washer that fits tightly and is no larger than the inner race of the bearing.

 

[BoatMan]

If you had bought a conversion kit from SSBC there would be a spacer in the kit that slides on the spindle before mounting the router. This moves the rotor out slightly and creates the effect of the spindle being a slight bit shorter when you tighten the spindle nut. You need to have a spacer on the spindle but the issue is that the base of the spindle is machined with a 3/32 radius. You'll have to make the spacer so it sits tight against the spindle base where the seal rides when assembled. I'd get a machine shop to make the spacer from round stock and have the matching radius machined into the I.D. If you're really brave grind the radius off the spindle and use a thick flat washer that fits tightly and is no larger than the inner race of the bearing.

I have the correct spindles from a 69 Polara w\ disc donor car. Not using my original 66 spindles.

 

[BoatMan]

Looks to me like you might have the '72 and later bearings. take the inner bearing and put it on the spindle, when it is all the way back it should fit tightly. If the bearing is loose on the shaft, you have the wrong bearings. Another issue when doing the conversion is that you must use rotors from 68-71 to fit the '69 spindle. The later rotors will not fit unless you use a '72 and later spindle.

Dave

Rotors are 69

Rear bearing is tight on spindle.

Thinking the races are not installed correctly...

 

[BoatMan]

yes the race is "pressed" on to the hub and should be completely seated against the hub...I used a socket and hammer to gently tap the race into place. there should be no "space" between the inside of the race and the hub. Not hard to do just go slowly.

Might take it into the shop in the am and have them press it all the way until it seats against the lip inside the rotor.

 

[Davea Lux]

Rotors are 69

Rear bearing is tight on spindle.

Thinking the races are not installed correctly...

Most likely explanation. Take a brass drift and see if they will move. Note that most of the Car Quest bearings are made in China or Taiwan, not the best choice for longevity.

Dave

 

[Davea Lux]

Note that the collar you see inside of the rotor from your photo should have the race tight against it.

Dave

 

[livininharrow]

i use the old race to drive in the new one. better than a socket because it fits perfectly. just take the old race to a bench grinder to take a couple thou off the outside. a no brainer.

 

[Rapidtrans777]

Like Dave said use a brass drift and a hammer. No need to take it them to an auto shop. Set them on a hard surface like a concrete floor. Use the drift and the hammer and drive them in until they are firmly seated in the hub. There should be no gap where the race seats into the hub. Alternate sides when driving the race, you'll get the feel of it. You will hear a noticible difference in the sound when it bottoms out. Don't forget to install the inner bearing before you set the wheel seal. As far as having to much play, seating the races all the way will give you even more end play, Thats a different issue.

 

[Big_John]

Ummm.. We need to get on the same page here.

You are talking about pressing the races in farther into the hub. If that was possible, that would make the problem you are describing worse.

Looking at the pictures, there is no way that I believe that the races can be or need to be pressed in another 1/4".

Looking at the pictures and reading between the lines, I think that you are talking about the races being moved so they are closer to the outside of the hub.. If that is so, you need to stop right now and regroup.

 

[Big_John]

Since we've established that the spindles and rotors are same vintage, let's ask some really basic questions...

First, you said the spindles off a disc brake equipped car. Are you 100% sure?
Do you have the original rotors? Test fitting the old ones would be a good "sanity check" right now.
Have you verified that you have the correct rotors? Part stores screw up all the time...

 

[Davea Lux]

Like Dave said use a brass drift and a hammer. No need to take it them to an auto shop. Set them on a hard surface like a concrete floor. Use the drift and the hammer and drive them in until they are firmly seated in the hub. There should be no gap where the race seats into the hub. Alternate sides when driving the race, you'll get the feel of it. You will hear a noticible difference in the sound when it bottoms out. Don't forget to install the inner bearing before you set the wheel seal. As far as having to much play, seating the races all the way will give you even more end play, Thats a different issue.

I suspect that once the inner race is fully set, the outer race will ride on the thicker part of the spindle and the play will disappear. Check the numbers on your old bearings like John suggested to be sure you have the right parts.

Dave

 

[Big_John]

Looks to me like you might have the '72 and later bearings. take the inner bearing and put it on the spindle, when it is all the way back it should fit tightly. If the bearing is loose on the shaft, you have the wrong bearings. Another issue when doing the conversion is that you must use rotors from 68-71 to fit the '69 spindle. The later rotors will not fit unless you use a '72 and later spindle.

Dave

Noting the Duralast brand....

Just for laughs, I looked on the Auto Zone site and looked up the part number for a '69 Polara. It is #5307
So, I looked up one for a '73 Polara and it is also #5307

Hmmmm.... Everybody go "Hmmmm" with me.

Ok... So for even more laughs I went to the Rock Auto site and looked up the same applications and they list a 7012R Raybestos rotor for a '69 Polara and a 7018R for a '73 Polara.

I think there is the answer.... and just another example why I don't buy parts at Auto Zone.

 

[Big_John]

Also worthy of noting... When you pull up the rotor for the '69 application at Auto Zone, it has the statement "Sell until depleted" in the description. That tells me that they will no longer stock that part... But!! For the '73 application, there is no statement like that.

Get in the zone....

 

[Big_John]

So... Thinking some more on this... If the rotors are the same except for the spindle size being larger on the later cars, and if they supplied the correct bearings for the '69 application, then the race for the inner bearing could be different. If it was larger, the bearing would sit down farther into the race and cause the issue... It would be pretty simple to check one against the other and maybe exchange the bearing races.

You can't tell from these pictures... but this makes some sense to me.

So compare the inner diameter of the bearing races.