Installing new front wheel bearings on a TR4a

[Tr4aJim]

Folks,

I am replacing the front wheel bearings on my TR4a for the first time. I bought front bearing kits from Rimmer Brothers which included inner and outer bearings plus the felt inner seals. After reading the shop manual, I have a few questions about the bearing installation procedure.

 

- To seat the bearings, the manual says to fit the hub and bearings dry, and whilst rotating the hub, tighten the slotted nut only sufficiently to remove slackness, back off the nut to the nearest hole, and punch mark the nut/hub position. Then remove it all, pack the bearings, refit and retighten the nut until the punch marks correspond. Is this the procedure you all follow? This all seems a bit imprecise to me. On US cars Ive worked on, the bearings are packed and fitted, then the nut is torqued to a specific load while turning the hub, the nut is then backed off one flat to the nearest hole. What method do you all use to seat the bearings?

 

- Regarding the inner felt seal, the manual says to soak the felt seal in motor oil and squeeze out the surplus oil. How much oil must be removed? Until it feels dry? Also when driving in the seals metal flange, how deep should it go? Until it contacts the inner bearing race, or flush with the hub flange?

 

Sorry if these seem like dumb questions, but I dont want to mess up my first attempt at this.

 

Thanks

 

Jim

[RogerH]

Hi Jim,

if the manual states to fit the hub before packing the bearings with grease does it comment when to fit the felt seal.

If the seal is too thick it will hold the bearings apart.

 

I can;t see grease in the bearings being a problem but the felt is an issue.

Make sure it does not stand too proud. Compare its position with that of the bearings etc before fitting.

 

I would follow the manual but without the felt seal. Then install the seal for final fitment.

The taper bearings do need a small amount of play. However this play may not be too obvious if the felt seal is too thick.

 

The felt is there to stop dust/dirt getting in. Simply remove excess oil by finger pressure.

 

 

Roger

[boxofbits]

Hi Jim

 

I think the reason they state to assemble it dry is so that you are measuring true bearing tolerances when pulling up the bearing with the hub nut rather than being offset by the grease. You can do it that way, but not absolutely vital as Roger comments above.

 

Regarding the seal at the rear of the hub, pressing in until it is flush with the rear hub face should be okay. Also once you have done a couple of hundred miles, re-check play in the bearing and tighten if necessary.

 

Kevin

Edited March 12, 2018 by boxofbits

[BlueTR3A-5EKT]

Hi Jim,

I am curious as to why you bought wheel bearings for your car from the UK when The Roadster Factory is on the same continent as you

http://www.the-roadster-factory.com/indexmain.php

Peter W

[Tr4aJim]

Thanks everyone!

 

I guess it was the phrases like “remove slackness” and “squeeze out surplus oil” that seems a little too open for interpretation. The same with their description of only setting the nut “finger tight”.

 

Roger, Kevin - the manual says not to install the felt seal until after the dry bearing fitting has been completed, so the thickness of the felt is not taken into account. Without the seal, it says to achieve an end float of .003-.005 inch, so that’s pretty snug. I guess the idea is to crush the felt somewhat to provide a tight seal. As for the seal oil, I squeezed out enough so it feels dry to a light touch. I will make sure to recheck the end float after driving a bit.

 

Peter - I do use TRF for most of my parts. However I am doing a full front and rear brake replacement, and I found that Rimmer Brothers had a full kit that was cheaper than individual parts from TRF (with shipping it came out about even). So I ordered the bearing kits as well.

 

Thanks again!

 

Jim

[RogerH]

Hi Jim,

I had a look at the grease seal this morning and the felt was quite thick (it shouldn't be).

Using a very sharp blade trim away any excess, The felt just needs to be in sight compression - 1 or 2mm squish.

 

Roger

[Tr4aJim]

Roger,

 

Here is the felt seal after I soaked it in oil and squeezed out the excess. Looks about 10 mil thick including the metal flange.

 

Jim

[RogerH]

Hi Jim,

that may well be too thick.

TRy assembling and see how it fits. If there is too much felt the bearings will not seat properly.

 

Using the assembly instructions in the book - dummy fit without the felt and note the position of the nut - then fit the seal you may find things don't sit nicely.

 

TRim the felt to suit.

 

Roger

[RogerH]

Hi Jim,

do a search of past problems http://www.tr-register.co.uk/forums/index.php?/topic/42057-tr4-front-axle-felt-grease-seals/?hl=%2Bfelt+%2Bgrease+%2Bseal

 

There are quite a few replies.

 

Roger

[jerrytr5]

Jim, that procedure is far too complex.

Grease the bearings, smear a bit of oil on the felt seal and assemble.

The seal housing should not touch the bearing.

Do the nut up tight spinning the hub as you do so until it becomes difficult to turn. This will seat the bearings.

Slacken right off and then tighten using a single finger pressure on your spanner.

Back off to the nearest split pin hole.

Check regularly. Taper bearings are not fit and forget.

Jerry

[monty]

I believe those bearings from Rimmers are an example of the cheap spares we sometimes have problems with. I pushed out the boat & paid a bit more to hopefully ensure quality & bought Timken bearings to suit. Worth paying a little more in my view.

Cheers.

[Tr4aJim]

Roger, thanks for the link.

 

Jerry, the procedure you describe is just what I was thinking of doing.

 

Monty - the bearings RB sent me are from a company called SCH (which I have never heard of). So I checked with TRF here, and they only sell Timken bearings, however they are $234 for the four bearings!!! I guess I had better practice my installation techniques with the SCH bearings before risking an install using Timken.

 

BTW - I asked Al at TRF if they had any issues with the felt seals they sell. He said theirs are the correct thickness.

 

Thanks again everyone for the input!

 

Jim

[Lebro]

+1

 

The bearing set from Rimmers are not the best, but they also do individual bearings of a higher quality.

 

Bob.

[Alec Pringle]

When it comes to bearings, ebay can be your friend . . . as can google.

 

Track down the correct manufacturer part numbers, not forgetting that a prefix or suffix (S for example) to the number can be critical, and start hunting by number, or by AN Other application. Similarly, cross reference to other premium bearing manufacturer part numbers and try those. Bearing prices can vary hugely between suppliers . . . . .

 

As a recent instance, I had to find axle and hub bearings for the Mallock - best I could find through the usual specialist suspects was more than £80 apiece plus the VAT. Then I discovered the same bearing was used on now-obsolete industrial refrigeration motors, and picked up a small box of them at just a fiver each, thanks to ebay.

 

As for the budget bearings that some Triumph specialists offer - personally I'd throw them straight in the scrap box, which saves all the effort of fitting them and then replacing after a very few thousand miles, probably along with whatever housed the bearing . . . . .

 

Cheers

 

Alec

[Tr4aJim]

Alec, I just started doing some searches for Tr4a Timken wheel bearings and found something odd.

 

TRF lists a Timken outer bearing for $67. I then checked two other large parts distributors here in the US; Summit Racing and Rockauto. Summit lists the outer bearing for $21, and Rockauto has it for $26. That’s a big difference from the TRF price. I wonder if Timken has different grades of bearing.

 

Jim

[Alec Pringle]

I've never heard of Timken producing different grades of bearing . . . . . no.

 

BUT note my previous comment about prefix/suffix letters which can be crucial - minor differences in specification for specific applications.

 

I haven't purchased bearings from a Triumph specialist for decades - too damned expensive for my pocket. I prefer to make the effort and shop around, as with the Mallock axle - there's a big difference between the five pounds and the thick end of one hundred, especially when the consumption is 4 bearings per season ! That justifies some internet time searching.

 

Cheers

 

Alec

[Tr4aJim]

Well I went on the Timken website and looked up the part numbers for a 65 Tr4a. Here’s what I found:

 

Inner bearing - 07100s

Inner race - 07210x

Outer bearing - 03062

Outer race - 03162

 

Interestingly they also listed a seal (480991) and the picture looked like it was the rubber kind, not felt. I sent them an email to confirm, in case that was a generic picture.

 

BTW - I went back to the Rockauto site and their part numbers matched Timken.

 

Jim

[Alec Pringle]

Hi Jim,

 

the s and x suffixes indicate, if I remember correctly, some form of edge or rim strengthening - there are, or at least used to be, plain vanilla 07100 and 07210 which are not adequate for our applications.

 

Well done for the investigative legwork, it can pay dividends !

 

Cheers

 

Alec

[monty]

Current price for Timken front wheel bearing set 03062/03162 & 07100S/210X is currently £49 from www.bearing-king.co.uk. I paid £48 2 years ago with good prompt service from these people. At the same time I found an original Payen felt seal on EBay for no money.

All fitted perfectly.

Cheers.

[Tr4aJim]

The price on Rockauto.com is $95 for all fourTimken bearings and races.

 

Rockauto shows the same rubber seal picture as Timken, but Rockauto says its a generic picture. Im still waiting to hear back from Timken regarding whether their seals are rubber or felt.

 

Monty, I went to the Bearing-king site and looked up Timken 03062/03162. It listed them for £29, but when I switched it to dollars, it said $234 !!!!!!!!! I didnt think our exchange rate was that bad, or its a hell of a shipping charge! ????

 

 

Update - I sent an email to Bearing-king about the price and they found and fixed a problem with their exchange calculator. The 03062/03162 bearing now comes up as $40.

 

Jim

Edited March 13, 2018 by Tr4aJim

[PYU940F]

I am putting back N/S front suspension at the moment and needed to replace Vertical link, trunnion and axle. The outer bearing race will not fit onto the new stub axle. It is a beautiful fit on he old axle but too tight on the new one by, I suspect, a couple of thou. I could force it on with the hub nut but then I would never be able to get the hub off. Is this a common problem with new axles and what is the fix? A couple of hours with emery cloth? A lathe job? Maybe a new bearing may be slightly larger? Any one else had this problem?

 

Simon

TR4a

[RogerH]

Hi Simon,

did you not try it on the counter. I thought that is what you were going to do when I left.

 

As you are a fair distance form the shop give them a call and explain what has happened AND ask them to try a new axle with a new bearing to ensure they fit.

Then either go and get it or have it delivered (at their expense) and return the duff one.

 

Not sure what would happen if it was simply turned down on a lathe. Is it machined and then heat treated ot the other way round.

 

Have you got a micrometer? Take a measurement. The bearing will almost certainly be a conventional fraction in diameter.

 

Roger

Edited March 13, 2018 by RogerH

[ChrisR-4A]

To allow for the freeplay on the bearings to be set does the outer bearing not need to move on the taper relative to the position of the inner bearing when tightening the nut?

In which case the position and size of the taper on the Stub axle is very import as the bearing must move for adjustment but not be loose so it rotates on the Stub axle.

 

Chris

[RogerH]

Hi Chris,

have a look here page 4.104 fig 2 http://tecb.eu/onewebmedia/TR4%20Manual.pdf

 

The outer race of the inner and outer bearings are located against lips in the hub.

The inner races of each bearing must be allowed to move on the stub axle to ensure it is tightened (plus the 0.004" play)

 

Simon has the problem that the inner bearing inner race is too tight on the axle and so it may either not go on fully or not come off.

 

The taper part of the axle just connects the two parallel bearing diameters on the axle.

 

 

Roger

Edited March 14, 2018 by RogerH

[PYU940F]

Yes Chris it does. Moss checked other axles and their latest batch have all have been manufactured 1/2 a thou oversize. Who said a Triumph was not precision engineering! I would have thought 1/2 thou would not make the difference between fitting and not, but t does. I was originally going to salvage my original axle due to concerns about build quality but I was persuaded to splash out £20 on a new one with the comforting reassurance that it was British Built. The bearing fits the replacement axle beautifully. Lets hope it is made in India.

 

Simon