Knackered Drive Shaft & Bearings?

[Bordfunker]

As some of you may know I’m in the process of rebuilding my 1200 Herald, and having rebuilt the diff oil seals, attention has now turned to the rear hubs and drive shafts.

Having stripped the brake components off one side I’m left with a drive shaft, trunnion/bearing housing and back plate, which has highlighted the fact that there is movement between the drive shaft and hub, and not rotational, but linear as per the photos below.

Which at the hub side translates to this.

Which means about 2-3mm of longitudinal movement, which I am assuming means at the very least that the bearings have collapsed, allowing the movement, and/ or the drive shaft is toast as well.

Therefore I am assuming I will be needing a proper Triumph spec hub and bearing puller?

Hence checking my interpretation with the combined wisdom of the forum before I start stripping things down.

Thanks in advance.

Karl

 

[thescrapman]

Yes

 it is knackered, and yes you need the correct puller.

[Pete Lewis]

Yes agree a proper hub puller is most likley needed and even that may need leaving on overnight and find its popped off in the morning

The bearing is a  tight  pressed fit on the shaft but a hand fit in its trunnion housing

There is a dimension to drift the new bearing onto the  shaft this is only a provisional position as fittng and tightening the hub nut

This pulls the shaft and positions the back plate  

Put the hsg in a vice and attack the shaft with a BIG mallet should shift the shaft out the bearing,  there is an adaptor made to utilise the hub puller to do this if needed 

Extra shreaded wheat job

Check the removed shaft for needle roller damage and the inner  oil seal fits back to front

Pete

 

[JumpingFrog]

I'd say there is a high chance that the needle roller bearing has eaten through the driveshaft as you suggested. This is very common even when the bearings seem okay.

Perhaps it might be better to try and find a good used driveshaft? However, Pete gives a lot of useful information if you choose to do the job.

P.S. See https://forum.tssc.org.uk/topic/3850-reproduction-herald-driveshafts and http://sideways-technologies.co.uk/forums/index.php?/topic/7973-spitfire-drive-shafts/ for information about the problems with some reproduction driveshafts. I've had no word as to whether or not anything has been done about this, but they still sell them.

 

[johny]

I think the axial play is going to be down to outer ball bearing wear so the shaft might be reusable. Wonder what it's like to turn?

[Bordfunker]

All, many thanks for the feedback, particularly with regard the replacement drive shafts, as although I don't intend doing huge mileage (once I finally get the car back on the road), I don't want to be having to do this again any time soon.

The hub is quiet when you spin it, in answer to Johny's question, which suggesst that the main bearing is OK, but as per Jumpinfrog's comments, I'm guessing that the needle roller bearing has failed, and potentially chewed up the drive shaft, allowing the fore and aft movement of the shaft.

Chances are I will simply reaplce all the bearing as a matter of course, but most likely with ones from the club or reputable SKF ot Timken ones.

Oh well, I know what I'll being over the bank holiday weekend then.

Off to find a puller now.

Thanks

Karl

[Pete Lewis]

any float has to be the main ball race, the needles just sit there and run on the shaft they have no position ability at all

sorry you need a bearing change , unless the shaft is a loose fit thro' the bearing..and thats unusual 

do read up on the way round the needle cage has to fit it has two options you only want one of them 

sorry about that 

Pete

[Bordfunker]

Pete, no probs, I'm planning on replacing all the bearings as a matter of course as they've probably been on there 50+ years.

Karl

[johny]

Surprised it spins ok as the ball bearing would have to be pretty shot for that much play. Could it just be loose in the trunnion housing? Dont know if you can buy complete half shaft assemblies already reconned....

[Pete Lewis]

Good call float in the hsg, might explain the smooth running and shift.

Pete

[Bordfunker]

Stupid question, but what controls the float in the housing?

I am assuming that the bearing is a tight fit to the taper, which is then held in place between the bearing housing and the back plate.

So does that mean that the bearing is no longer a tight fit on the taper?

Karl

[johny]

The ball race bearing is the only locating point so a lot of wheel side thrust must be taken by the u/j and diff. The bearing is press fitted on to the shafts parallel section not the taper which is for the hub and I don't remember there being a shoulder for it to go up against either so I think it's just done by measurement. Best to look at excellent diagram in the free to download work shop manual.....

[Pete Lewis]

The only taper is the end of the shàft and the hub flange there is no taper to locate the bearing its just a tight press fit on a straight shaft

The degree of fit, interference is all that hold shaft and bearing in place there are no shims in the housing just a paper gasket on the face

The dimension is just a start point to enable the hub and it nut to fit, when you do the nut up it repositions the shaft and bearing .

Makes you wonder how it all stays in place when you hurl round a roundabouts

Pete

[Bordfunker]

Picking up a hub puller tomorrow night from local club meet, so should get a chance to crack open the hub and bearing housing at the weekend.

Karl

[Pete Lewis]

Dont rush the hub will either pop  off  with the puller , or when stubborn, walk away   and leave it  for some time 

Even overnight and it pops of whilst left under load 

Pete

[68vitesse]

I always leave the hub nut on a good few turns, the hub can fly a surprising distance when it releases. Have also on accassion freed a very stubborn one like you would a ball joint while they are under tension from the puller.

Regards

Paul