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MG Midget and Sprite Technical - Wheel Bearings?

Hi All

I am just putting the front hubs back together after changing the brake discs and wheel bearings.

I have tightened the castlated nut fiairly tight nut not yet torqued it up. I seem to have some play in the bearings / half shafts, I am sure they are worse than the old ones!!

Is it possible that the wheel bearings are at fault or should I be looking else where?

Thanks for any help on this one.

Regards

Tony
A Brough

just wait for it
now you've opened a snake pit
Onno Könemann

Tony

We've all been through it...no easy answer.

I'm sure there will be more posts coming, from folks much more knowledgeable that meself.

:)Dave



Dave Rhine ('78 1500)

I had the same thing happen to me last Fall, the new bearings felt looser than the 32 year, old worn out bearings I replaced.

In fact here's some info you might want to read:

http://smithtr6.com/bearings.htm
Dave Rhine ('78 1500)

Tony
I had this problem with my wheel bearings, I decided to take out the spacer, I measured it with a micrometer then removed some material from the end of it just buy rubbing it on a flat surfacce on some fine wet & Dry glass paper I only removed abour 2 thou and the bearings are a lovely fit now with no play. This was my method of sorting the problem but I am sure others here will offer more solutions
Thanks Ian
I Pickering

I nearly am finished with my work on this subject. The page Dave (thanks Dave) refers to will have one or possibly two more updates coming.
The stress modulus section near the bottom of the page might be found interesting.
The good news is that after nearly a year of searching I have finally found a source for the correct bearings and they are still manufacturing them. I purchased a set and they are on my kitchen table. This Monday I will do some final measurements to make sure they are face adjusted or not. Then I will document the installation and include an explanation of how to correct the spacing if they are too tight or too loose as some have reported when replacing their bearings.
In the meantime I am working to have a supplier handle these bearings so they will be readily available.

There has been a lot of research done for this project. And there has been much input from many people including those on this forum. I have tried to be as objective and nonjudgmental as possible. The information presented is to show how different bearings fit and how that fit may effect the strength of the assembly. After all is said and done, remember, you are working on your own car and the decision as to how to proceed it yours and yours alone.
tomshobby

Tom

Looking forward to your final report!

:)Dave
Dave Rhine ('78 1500)

Thanks for all the replies.
Onno you are right the snake pit is open!

This is taking me back 35+ years to my engineering apprenticeship, at least one career ago.

After reading the posts and links, I think that I will try Ians tip of taking a few thou off the spacer as if as I imagine the problem is with the radius on the inner edge this would mean that the bearings are not going far enough back and so not in contact with the outer lip in the hub, so this would allow the outer bearing to seat further down the shaft.

The link supplied by Dave to Toms article is very interesting reading, but I would be grateful if someone could assist me in the following area:
If I was to assemble the bearings without the spacer, should I torque it all down as per the manual. My reason for this is that is the bearing is not supported on the inner race then the outer race would butt up against the step in the hub allowing the inner race to be put under undue pressure and increasing friction and load on the ball bearings.

Thanks again for all your help

Regards

Tony
A Brough

Tony,
If you take a look at my drawing of the original bearing configuration it shows where shins might be used to correct the spacing for when the bearings would be too tight or too loose after torquing the nut.
The method Ian used addresses the same problem and I see he takes care to maintain the end of the spacer to be flat and parallel.
Ian, what would you do if the bearing was too tight?
tomshobby

Or you could simply read this, buy the most correct bearing on the market and all your play problems will be over.

http://www.midgetregister.com/workshop/77

Robert (Bob) Midget Turbo

Hi Bob,
On 03/03/2010 I was told by Motion Industries that bearings NSK no’s 7303BEAT85SUN and 7205BEAT85SUN have been discontinued. Otherwise I would have stopped there.
Do you have other information?
tomshobby

Hi All

Thanks again for the help and info so far.

I have found these bearings listed as in stock, but need to call on Tuesday to check availability.

They are described with metric dimensions arethese going to be the same as quoted by Bob

SKF 7303BECBP Single Row Angular Contact Ball Bearing 17x47x14mm

SKF 7205BECBP Single Row Angular Contact Ball Bearing 25x52x15mm

Thank you

Tony
A Brough

Better not to fart about with spacers and inferior bearings, take Bob(Roberts) advice and fit the readily available SKF face adjusted bearings,I did last year and after 5000 kms. of rallies and track regularity competition there is no detectable play. Cheers Alistair.
A.G Peters

Alistair

I agree but where can I get them?

Cheers

Tony
A Brough

Anyone know of a US supplier?
Dave Rhine ('78 1500)

The 7303 and 7205 are fine as far as the space between the bearings. Just make sure they fit against the stub axle face. Because of the radius difference there is usually a need for a shim in that location.

The only bearing I have found that fits correctly in all ways is the original 34LJT25 inner bearing, and to match, the 3MJT17 outer bearing. Both still being made. Earlier today I checked to be sure they were face adjusted and did a fit test of the inner bearings. They passed both tests. I need to get a tub of bearing grease and plan on installing them tomorrow or Tuesday.

The pros of the 34LJT25 and 3MJT17 bearings is that they fit perfectly. They are, in fact, OEM bearings.
The cons are the cost, close to twice.

The pros of the 7303 and 7205 bearings is that they cost about half.
The cons are that to fit they need a 1mm shim against the stub axle face.

All said and done, either should work.
tomshobby

Hi Tony,
I am in Brittany and get my bearings from a fishing boat supplier!,he orders from SKF France and they are here in 24 hrs.,approx. €90 a side.If the hub and spacer are in good order a shim is not a good idea,Skefco will tell you never, and they know a bit about bearings!
Slainth,Alistair.
A.G Peters

Hi A.G.,
I would like to know why Skefco recommends never using a shim is not a good idea. And exactly where you are referring to. Between the inner bearing and stub face or between the bearings.
Thanks,
Tom
tomshobby

Tom who makes the original bearings? are you sure they are still made? thought they went out of production a good number of years ago? What manufacturer are they now? they used to be RHP who are now NSK who certainly do not manufacture them?
Robert (Bob) Midget Turbo

IIRC it was these guys that seemed to list the troublesome 34LJT25 http://www.crewe-eng.co.uk/bi/SAR%20Bearings%20Impex%20Stock%20List%20Sept%2007.txt , might be worth giving them a ring to check current stock. Not actually tried to get any from a bearing stockist but that reference number showed up as an automotive special on a few websites worldwide.
David Billington

Hi Bob,
They are RHP bearings and made in England. Currently they are being made in lots of 10 as needed for stock. I purchased mine through Orinoco Bearings.
They are a little pricey this way and it is why I have not made all the information available yet. I am working to get a supplier to handle them in hopes of getting the price down.
I made several dimensional checks and they are exactly what I was looking for. And they are exactly the same in every detail to the original bearings that were in my car.
I installed them today and could not be happier with all aspects of the fit.


tomshobby

Thanks David

I have just ordered two of each at £24.50 and £28.60 + vat from
Bearings Impex
Queen Street
Crewe
Cheshire CW1 4AQ

Tel.01270 585211

I will post back when I get them

Thanks again to all of you on this.

Regards

Tony
A Brough

Hi Tom,
Skefco told me not to use a shim as the hub is being constantly heated and cooled and a shim would add a fourth type of metal to the mix.As it happens mine were fine without.
Cheers AG
A.G Peters

Thanks AG. It turned out I also did not need a shim. Thanks again for the information.
tomshobby

Hmmm, so if the 34LJT25 and 3MJT17 bearings are the original ones, and can still be bought, and fit properly, has this been a complete wild goose chase, a non-problem, the whole time? (As long as one buys the right bearings and not what the mainstream MG suppliers try to pass off as correct, but cheap and nasty)
David Smith

Hi David,
All I knew when I started my quest was that the bearings I was buying for my own car simply did not fit. And after all the time and effort I am very happy with what has been found and thoroughly confused as to how this ever became an issue in the first place.

I will say that I was, and still am, amazed at the determination by suppliers and manufacturers that the bearings they have fit when they clearly do not.

Then there is the willingness to discuss this subject with an open mind on this forum. Without that and the ideas and help that followed it most likely would never have happened. I am sure that there were times when most would have been happy if I would have just gone away.

There is one thing left though. That is to get suppliers to stock these bearings.
tomshobby

Tom,

I know they're not on your side of the pond but I've always found Sussex Classic Cars (www.sussexclassiccar.co.uk) to be very helpful & knowledgeable. I wonder if you might approach Greg and ask if he'd be willing to become a supplier for the correct bearings.
As usual, I have no affiliation with them, just a happy customer.

-Craig
C Robertson

Very curious Tom, if RHP are no longer in business then how can they be the manufacturer? are these then just NOS. If someone would manufacture the original spec bearing then that would be marvelous to say the least.

Tony let us know what you get please?
Robert (Bob) Midget Turbo

Hi Bob

Still waiting :-) will pot back with pics when I get them.

Cheers

Tony
A Brough

Bob - from the NSK website:
"In 1990, NSK acquired UPI, which owned RHP, the biggest bearing brand in England."
Don't they still own the brand?
David Smith

Bob, Not sure. Maybe you can help sort it all out.
I found the source with a request to this site. http://ransomeandmarles.co.uk/

I then got a reply and asked the following questions and received the response with the answers to my questions as follows;

1) How many do you have?

Currently less than 10 pieces.

2) Do you or can you still make them?

We have them made specifically to order.

3) What is your minimum order?

To manufacture the quantity would be 10 pieces.

I only need two, but no one has been able to find them, including vendors and owners of these cars are anxious for correct bearings.

We can supply you 2 pieces at £45.00 each nett.

4) Can you verify the dimensions? D = 52mm; d = 25mm; B = 15mm; and most important, r = 2mm or up to 3mm

Confirmed.

Regards

Graham
The dimensions referred to the drawing included here.

The bearings I received were clearly marked with RHP and the numbers, England, Thrust, etc. Exactly as the original bearings.
tomshobby

Here is the drawing I referred to.


tomshobby

At least I finally got my front suspension back together. You can see from the dust that it has been a while.


tomshobby

Fit taper rollers
Alex Sturgeon

Alex
if you don't want to read the whole thread than don't respond!

to sumurise
people started fitting taper bearings because the original replacements where rubish.
this is because they are only simular to the proper originals and not to exact specs
the whole search has been to find them in the proper original spec.

with the proper spec original bearings there should be no reason to fit tapers
Onno Könemann

Hi Alex, I did install taper bearings first. And that is what started this. They simply did not fit correctly.
This thread and the article with CAD drawings and photos can help you understand what has been going on. http://smithtr6.com/bearings.htm

There is one more thing that I have not yet mentioned and did not realize until two days ago even though I have read it many times.
Having had both new taper bearings and now these new ball bearings in my car I can say there is a huge difference in ease in which the hubs rotate with the ball bearings.

When this all started I was a staunch believer in taper bearings and that it would be a great upgrade. No longer so, since then I have completely changed my position and now am completely in favor of ball bearings for our cars. Everything kept pointing that direction and after my new ball bearings were installed there is no way the results can be ignored.
tomshobby

The bearings arrived today and they are RHP, NOS by the looks of the box. I have enclosed a picture and will post back when I have fitted them.

Cheers

Tony



A Brough

Got the first side on, no play and thats just over hand tight.

Job Done!

Thanks to everybody who contributed.

Cheers

Tony
A Brough

How are the bearing numbers made up? Are they a composite code for the specific attributes, or just a part number?

The reason I ask is that I have two boxed sets of wheel bearings that I have had, unopened, on the shelf for quite some years. One is in a Unipart box and the other labelled Premier. They were bought at different times.

Looking at the numbers on the bearings both sets have the same numbers:
11/MJT17 and 39/LJT25, all are RHP bearings

So the numbers are close but in both cases have different numbers at the start, with an introduced / before the letters. What significance does this have?

Guy
Guy Weller

Yes these look like original NOS RHP bearings. They are as the drawings I circulated to everyone over the past few months and were made as special 20 degree angular contact bearings that were "face adjusted" and had a special inner bearing face radius to fit the stub axle face correctly

As I stated RHP went out of business a long time ago and were renamed/taken over by NSK.
The nearest bearing made today is the 40 degree angular contact bearing with face adjustment as described here.
http://www.midgetregister.com/index.php?option=com_content&view=article&id=77&Itemid=66
As described above angular contact bearings are far superior to tapers in this configuration

The 40 degree bearings are spot on for our application except for one problem (unlike other option bearings that have numerous problems) that is the radius of the bearing inner race that may not fit the stub axle fillet exactly. This problem exists in ever modern bearing and may or may not be a fault although it is not correct but to my knowledge has never caused a problem.
However it would be great if the original bearings made to original drawings could be purchased. And I find it incredible that a company is willing to make these in batches of only 10 for only £45.

That said R & M refered to above are I think part of NSK and I will gladly make enquiries through my friend upon returning to the UK next week. I am at present in the USA.
Robert (Bob) Midget Turbo

Thanks Bob,
So the fact that mine are RHP is a GOOD THING?
But what about the prefix numbering of 11/ and 39/ preceding the MJT17 and LJT25. What dies that refer to?

It differs from the references given earlier in this discussion
Guy Weller

Guy,
The short answer to your question about the bearings you have is they probably are not suitable, but without seeing the drawing its impossible to say.

I used to work for Hoffmannns which became part of RHP and from memory the number means the following:
LJT 25 means light journal 25mm bore.This is the standard bearing.

The prefix number is the modification or special number i.e. 34 is the 34th modification to the original standard bearing.

Likewise MJT 17 is medium journal 17mm bore.

The fact that your bearings are of a later modification does not mean they will fit although they might as the mod might just be a larger radius elsewhere or something similar. These mods are normally quite small as the overall dimensions and raceway will be the same. It could be something as simple as a different material for the cage for example. The crucial thing is that its unlikely that they will be face adjusted and as we all know that is the most important part. You can check this of course if you have the means to check the faces.

The website Tom found for R&M is interesting as on seeing that I searched for Hoffmann bearings and came up with a near identical site for them and a phone number almost identical as well. I think the STD code suggests Leeds area so not related to an old RHP site. I think it most likely that they are a supplier with NOS or if they haven't got it can get it made in small batches by a small bearing manufacturer somewhere. I know some people from the old Hoffmann site started up in a small way on their own when it closed and no doubt ex R&M staff may have done the same elsewhere. No idea if they are still going though as this was several years ago.

Trev
T Mason

Trev,
Thanks for the explanation of the numbering system.
The bearings I have are boxed and marked for MG Midget / AH Sprite. I understand from earlier discussion here that this does not necessarily mean that they are correctly made, with the required radiused edge to the inner race.

But I am not sure why you think that "they probably are not suitable". How would I check if they are face adjusted?

Guy
Guy Weller

Guy,
Sorry, to be clear they will fit as they are the right size, but as well documented here the radius and the face adjustment is the important thing. As they are marked for Spridgets and are of a later variant I suspect they will not be face adjusted, but I could be wrong. This is what I meant by not suitable as not face adjusted usually means play.

To check the faces you ideally need a surface table or other dead flat surface and a dial indicator capable of measuring 1/10,000 inch. Lay the bearings flat with the inner faces uppermost(the faces that contact the spacer) and then set the dial indicator on the outer race face and then move it to the inner race face. The measurement should be identical. Then do the same to the other bearing.

To understand why this is important it helps to understand how bearings are made. Normally the inner and outer races are made seperately and every dimension has a tolerance of a few 10,000 inch. If the outer race is made to max tolerance and the inner to min for example there can be quite a difference in the two faces. In most applications this is not an issue, but because the hub and spacer are the same length it does matter for these bearings. To overcome this the two races are ground as a pair and therefore fit perfectly.

Trev
T Mason

Thanks Trev, now I understand.
Guy Weller

A newer term used in place of "face adjusted" seems to be "FLUSH GROUND". I had a few replies use that reference. Can anyone verify that they mean the same?
tomshobby

I am surprised that the bearing designation actually means so little. If MJT25 only defines it as a Medium Journal bearing for a 25mm shaft, what about all of the other possible variations? There must be dozens of different sized bearings that would fit this designation. I was expecting a rather more complex interpretation of the numbering!

Guy
Guy Weller

Guy, I agree with you, and that is probably a big part of why we have this problem in the first place!

Good old BMH, they developed a special bearing that made sense as long as their original source made them just right, but because of the limitations of the industry numbering system, that made it hard to be clear about whether the part is the right one or not, now, years and years later!


Norm
Norm Kerr

Guy,
There were literally hundreds of variations of basic bearings, the basic designation changing for all sorts of reasons (such as ball, roller, angular contact, thrust,sealed, metric,imperial, the list goes on-just look in an old catologue)and it was not unusual to start with a basic bearing criteria and modify it to suit a customers requirement. As you can see from your bearings there were at least 39 variations of LJT25.

There are also suffix letters too on some bearings usually relating to sealed units and also a K type which has a circlip groove in the external diameter. The whole designation thing is far too complex to go into here but does follow a logical pattern.

Put simply you could have pretty much anything you wanted in those days. Don't forget that although it seems odd to specify non standard, car makers would order in the region of 50 - 100,000 a month every month. Today designers tend to use something standard off the shelf as this is obviously cheaper. Ideas also change as we used to make bearings upto 5 feet in diameter, which were usually 1 offs, but modern thinking puts a lot of smaller standard bearings on end running on a steel track.

Tom - not heard the expression flush ground but would make sense that it means the same but couldn't verify it.

Trev
T Mason

Trev,

I know what you're saying, I had contact with SKF about 2001 regarding the Sierra /Granada rear bearings and that was a special IIRC, details readily available but the bearings had to be sourced from Ford.
David Billington

David,
When I bought bearings for my Sierra box from a bearing factors, I was at first told that two of them could only be obtained from Ford. But after some discussion he then agreed to supply them on the basis that it was a one-off purchase for an obsolete gearbox. It wasn't that the bearing was special, but that Ford operated a restrictive cartel.

Trev, of course I understand that there are hundreds of bearing variations possible. That was exactly my point. What I expected however was that there would be a part number or bearing code that identified the particular variant to avoid confusion!

Guy
Guy Weller

Sorry guy I was answering the post above your own.
As we can see Trev knows as much about these bearings as any of us so I can add nothing to what he has said to you Guy :)
Robert (Bob) Midget Turbo

Ahh! That makes a difference!
When I first posted my bearing numbers with the different prefix Bob immediately responded with
"Yes these look like original NOS RHP bearings."

From then on I therefore took it that the differing prefix numbering was insignificant - leaving me wondering what distinguished the different variations. Hence my persistent questioning. Sorry Trev, I wasn't doubting your expertise - just puzzled.

The subtleties of e-mail mis-communication!

I think I will try these bearings for fit - but with not very high hopes!

Guy
Guy Weller

"Robert (Bob) Midget Turbo, England

Yes these look like original NOS RHP bearings. They are as the drawings I circulated to everyone over the past few months and were made as special 20 degree angular contact bearings that were "face adjusted" and had a special inner bearing face radius to fit the stub axle face correctly"

Bob, my curiosity got the best of me. Was the 20 degree special for these cars? Would there be a benefit to one or the other, 20 or 40?
tomshobby

Guy,
Didn't think for a moment that you were doubting me. I realise its not obvious how the numbering works. The only way of knowing what the differences are is to look at the drawings and compare. The prefix is the one bit thats not obvious, as it was just a matter of who asked for a change first so 1/XXX could be entirely different to 2/XXX etc. In other words 2 is not an improvement on 1 as it would be reasonable to assume if you had no knowledge of the process.

Tom - to answer part of your question to Bob the 20 degrees was not special to this application. A whole range of sizes was made to this spec. The only special bit is the radius and face adjustment. If I remember correctly (long time ago now) I think all these types of bearing were 20 degrees. I certainly can't remember any 40 degree ones. As to the benefits of either, logic would suggest that 40 would cope with side loading better (i.e. cornering) but might increase rolling resistance, but no science to back this up.

Trev
T Mason

Thanks Trev,

Interesting you wondered about the rolling resistance being a possible difference. A couple months ago I asked that same question on my web page and a few different bearing companies but did not get an answer.
tomshobby

Yes I naturally agree with Trev, the 20 degree bearing in itself is not special but the bearing specified by BMC for this kind of set up (Spridgets, Morris etc.) is a modified 20 degree bearing and has thus the initial number. The drawings that I believe you received describe to RHP what atributes BMC wanted in the bearings. This ofcourse was face adjustment and a larger than normal radius in the area you have investigated and identified Tom :)
I am not sure 40 degree bearings were available at the time but I certainly choose them to do my front end because they are the only angular contact bearing available that can give us face adjustment. The 20 degree bearings on sale today do not have this feature available. Just a pity about the radius issue. :)

Robert (Bob) Midget Turbo

Bob, the radius issue is really the "pity" of it all.

As Tom said
"I will say that I was, and still am, amazed at the determination by suppliers and manufacturers that the bearings they have fit when they clearly do not."

It is amazing to us that so many bearing manufacturers wouldn't bother to check their product and just declare that it would fit because the part number in the book said it would when the radius was too small to fit the Spridget spindle. Even when given good evidence they would retreat to their manuals and repeat just what they said about the application and the part number that would work. I applaud Tom for all his hard work and preserverence to come up with a bearing that would work and the corrective action to take in case the radius was a little small.
Bill Young

It makes me wonder just how many of the front spindle failures that have occurred on these cars over the years, were they all because of the bearings used with a too small radius?

We may never know, but it would have been super easy to have happened any time someone bought an "identical" bearing set ("well, the catalog says it will fit!").

Maybe equal parts that, and the folks who left out the spacer thinking THAT shouldn't make any difference.

While all this time, we just thought it was because the quality control at BMC was poor!

Norm
Norm Kerr

Right, I am going through this bearing assembly process.

First point - I am correct in assembling with the two "Thrust" faces facing each other, i.e both face the spacer in each case aren't I? - Just to be sure!

Secondly, I was going to put the inner race onto the spindle in order to check that there is no clearance at the back caused by the radius issue. But am a bit concerned that it may bind on the axle and I may not be able to remove it again to install properly without destroying it. Which rather ruins the whole idea! Any thoughts on how to do this?

Guy
Guy Weller

1 - yes;
2 - you can't unless you have the right tool to measure the radius
David Smith

David
1. - thanks!
2. - Tom's article suggests - by inference from the photos - putting the bearing onto the spindle and then checking by sliding / attempting to slide, a feeler gauge behind the bearing to check there is no gap.

I guess I would need a knife-edge bearing puller to get it off again? Something not in my tool box.

Guy
Guy Weller

Bill Norm

The main issue with these bearings over the last 20 years has not been the radius problem or indeed the failure of the stub axle. It has been the play induced into the bearing by fitting CHEAP non face adjusted bearings.

To cure this people have done 2 things

1 fitted tapers, (Complete with radius problem)

2 machined the spacer to take up the slack caused by these simple cheap bearings. (Complete with radius problem)


There are a couple of things to note.

It is NOT the fault of bearing suppliers such as NSK and SKF to name a couple. It is primarily the fault of Moss, MGOC and many other suppliers who have not understood the problem and have simply supplied cheap bearings that match the BASIC dimensions of the original items.

As I stated above thousands of these poorly supplied bearings have been fitted to BMC vehicles over the past 20 years (morris, mg, austin etc) without problems of the axle shearing but all having too much play induced into the wheel and all having the radius problem.

From my point of view I am more than happy to fit the bearings that are face adjusted although they "may" not seat fully against the axle face. If thousands have been fitted in this manner for 20 odd years then I am happy to accept they are pretty good. The face adjustment will give me the ability to not have play in the bearing and make use of the spacer as it was designed. This will have to surfice me, and I would hope others until someone can make a bearing that suits the oriinal exactly, at which time I would change to that spec, until then I will remain as I have described.

Robert (Bob) Midget Turbo

I have fitted one side and they seem good. But maybe will settle in and go slack after a week or two!

What I did was to assemble with a 10 thou shim added to the spacer. This produced discernible endfloat with the castellated nut tightened up and aligned to its split pin hole. I used a dial gauge on a magnetic base and tried to measure the end float. It wasn't easy to get consistent measures - I probably should have washed all of the grease out first. But the average of readings was coming out at about 0.009". So in theory this would give a 0.001" pre-load Either that or it would crush the bearing! On the basis that the grease was taking up some of the available endfloat I took a gamble that the end float was about right to allow me to re-assemble without the shim. It seems to have worked, so I am keeping fingers crossed as its the the best a non-engineer can do!

Guy
Guy Weller

Front hub play again and again!

The PO was checking the play in the front wheel bearings before setting the to in. I have just replaced the ball bearings (an shimmed them) till there was no play at all while on the bench. It wasn't easy to get consistent measures – Me too probably should have washed all of the grease out first. I did not.
After 100 miles and some very fast cornering, there is 1- 2 mm of play measured on the tire rim…. What play is normal? What is acceptable? How much shim do I need to stop the play and not crush the bearings. It is a lot of work to get the bearings out and shim them again.

Flip
Flip Brühl 948 frog 59

"1 - 2 mm as measured at the wheel rim" .... are you sure that this movement is wheel bearings and not on the king pins? I think that to me that little would be acceptable.

I drove about 90 miles today and it was very noticeably smoother and felt much better than before I renewed the bearings. Tomorrow I will jack it up and see if there is any discernible slack developed.

Guy
Guy Weller

What bearings are you using that need to be shimmed?
Robert (Bob) Midget Turbo

I used the7205/7303-bearing combination; at the left side the radius of the axis was all right, the bearing was flush with the spindle face so no gap. The right side had a gap. I shimmed the 0.020 gap between hub and 7205 with a 0.030 shim witch I glued to prevent it to slip into the radius. So the inner circle of the shim is bigger than the axis with radius.
I shimmed the 7303 with a 0.030 shim as well.
I have used new swivel axles and axle pins; there is no play between them.
How much play in the bearings is acceptable?

Flip
Flip Brühl 948 frog 59

This thread was discussed between 03/04/2010 and 21/04/2010

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.