end play in 521 axles

[datsun 521 ute]

I am in the process of changing the rear wheel bearings in a 521 ute and the axle seems to have about 4-5mm of play in it still, that is after putting in the new bearings. It seems the bearing needs to go further onto the axle but it's as far down as it will go.

Any help would be much appreciated.

[72wagun]

I replaced the rear bearings in my 521 quite a while back, and I remember that there was a spacer that slides on the axle before the bearing. If that spacer is put in upside down, it will cause end play in the axle. The reason is that the hole in the spacer has a sharp corner on one side, and a radiused corner on the other to match the radius on the axle.

 

Some of this was discussed toward the end of this thread a while back:

 

http://forum.ratsun.net/showthread.php?t=12416&highlight=521

[datsun 521 ute]

I'm 99% sure i got the spacer on the right way, i put the radius edge facing down as i slid it over the axle.

[72wagun]

I'm 99% sure i got the spacer on the right way, i put the radius edge facing down as i slid it over the axle.

 

Yep, that's right (assuming of course your axle is standing on end:)). The radius would go toward the flanged end of the shaft. 4-5mm is a ton of play. Is this with both axles installed?

 

I'm sure you've already made sure that the 4 nuts behind the backing plate have closed the gap completely between the two flanges back there.

[datsun 521 ute]

Have done the whole thing twice making sure spacer is on correctly and bearing all the way down.

I did change the diff centre over to have a more suited ratio, this was the cast iron type from a 85 Nissan Bluebird (910). Does the tip of the axle actually rest on the shaft that goes through the centre of the spider gears or centre gears. Was thinking maybe the shaft could be thinner causing the axle to move in the 4-5mm.

Other side still has wheel on and on the ground, so don't know about the other side.

Would it be an issue if i removed the spacer?

Edited July 18, 2009 by datsun 521 ute

[72wagun]

Have done the whole thing twice making sure spacer is on correctly and bearing all the way down.

I did change the diff centre over to have a more suited ratio, this was the cast iron type from a 85 Nissan Bluebird (910). Does the tip of the axle actually rest on the shaft that goes through the centre of the spider gears or centre gears. Was thinking maybe the shaft could be thinner causing the axle to move in the 4-5mm.

Other side still has wheel on and on the ground, so don't know about the other side.

Would it be an issue if i removed the spacer?

 

I don't know much about the differential area. I only changed out the bearings and seals at the wheel, and left everything in the middle alone for now. I do remember that the book gave 2 specs for axle end play (they were in thousanths of an inch). One was with both axles removed (more play I believe), and the other was for the opposite axle still in place (less play).

 

I'm guessing that the 3rd member swap is causing the issue. There are not many other things to check out at the wheel. This would be for someone else to answer who knows about 3rd member swaps.

 

I don't think you want to remove the spacer. The spacing on this whole system is pretty precise. It needs to be within the end play specs of the book. It sets the correct bearing tension on the inner and out bearings. It's just like the taper bearings on the front wheels, but the bearings are just spaced a lot farther apart, and you can't adjust bearing tension by just turning a hub nut. You have to use different thicknesses of shims at the axle housing flange.

 

Also, it's been a while since I looked at this, but I think it could cause your outer seal to contact the axle in the wrong place. If the seal gets off of the smooth seal surface on the axle, it might get chewed up pretty quick.

 

I guess it's also possible you could have just gotten the wrong bearing.

Edited July 18, 2009 by 72wagun

[datzenmike]

620 and 720 axles (and others) have copper shims between the passenger's side axle tube and the backing plate for the brakes. Adding or subtracting shims will move the axle in or out to get a 0.001"-0.006" end play.

[datsun 521 ute]

I do remember that the book gave 2 specs for axle end play (they were in thousanths of an inch). One was with both axles removed (more play I believe), and the other was for the opposite axle still in place (less play).

I guess it's also possible you could have just gotten the wrong bearing.

 

You don't happen to have these specs do you?

 

I took the bearing and seals in with me to make sure they got the correct part numbers, none of the parts stores had the 521 on record so I went to a bearing company.

 

620 and 720 axles (and others) have copper shims between the passenger's side axle tube and the backing plate for the brakes. Adding or subtracting shims will move the axle in or out to get a 0.001"-0.006" end play.

 

Thanks datzenmike but unfortunately I have about 4-5mm of play when the axle is in.

[datzenmike]

If you have any shims, take some out and it should remove some space. All the axles I've taken apart have 4-7 shims in them.

[72wagun]

You don't happen to have these specs do you?

 

I took the bearing and seals in with me to make sure they got the correct part numbers, none of the parts stores had the 521 on record so I went to a bearing company.

 

 

I've got a 510/521 Haynes book. It has almost nothing about the 521 rear axle. I used a Haynes 620 book I have because it has a lot more information. It says:

 

"If both axleshafts have been removed, install the first one and obtain axial end play of 0.012 to 0.059 in..."

 

Later it says:

 

"...when installing the second one, an endplay of 0.0008 to 0.0059 in. is required"

 

I thought maybe that 0.0008" was a typo, but they also give the amount in mm, and it is the equivelent amount.

 

Like datzenmike says, if your shims add up to about what you have in end play, you could probably remove enough to fix it. Otherwise, something else is going on.

 

I got bearings for my 521 from www.rockauto.com

[datsun 521 ute]

Thank you both very much for your input and help but the problem has now been fixed, it was the diff centre.

How I mentioned in a previous post about the axles end play may be supported by the shaft in the middle of the centre gears in the diff centre. Well that was why, the centre I used was from a later H190 that used ball bearing wheel bearings and the shaft going throught the middle of the centre gears was solid and quite a bit narrower giving the axle room to move in and out. Sourced a 620 centre and all back together only have to bleed brakes now.

[4.0lratsun]

ive just fixed this same prob on a 78 kc that i put a 3.55 center out of a car with disc brake rear and all you have to do is take the spacer off the spider shaft of your old center and put it on the shaft of the new center you want to use