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MG Midget and Sprite Technical - clutch release bearing

has anybody seen or used the roller clutch release bearings advertised on eBay?
Item number 165206910929
I realise the price may seem high but I'm more interested in opinions as to how good they are. or not!
aj robinson

AJ - try messaging Alan Anstead here as he makes them.
Not sure who you're referring to on ebay but I have a Peter May one (bought before I knew about Alan's) and it's worked fine for about 12 years.
Jeremy MkIII

I have been making roller release bearings for about five years. These days I only make them for 1275s using a stock diaphragm clutch. Out with the carbon release and in with mine. No modifications just fit & forget. Some garages now fit them to customer cars.
The spigots are CNC and the backplates laser cut. I weld the components in a jig. The bearing is as used on a car from a major manufacturer. It has the ability to run off centre.

I can be contacted at alan dot anstead at btopenworld dot com.

I no longer make release bearings for 948 or 1098. At one time I made CRBs for these cars by fitting a deep groove ball bearing to an original casting and topping with a bronze faceplate. The castings were all over the place dimensionally: some needing sleeving before boring. Not all were suitable for conversion. The original casting can crack. Strangely the castings that were the better for conversion were those that recieved complaints of early carbon failure: the ones where the carbon was given additional security with a roll pin.
The 1098 version I developed through to a third series using a roller bearing. I no longer make those as I was spending too much time on the lathe.

An Imp / Davrian enthusiast Robin Human started making clutch release bearings for those cars. They use a 948 clutch release bearing for a Sprite / Midget. I purchased one but was dissatisfied with the spigot measurements. Robin has now altered his measurements replacing my original purchase with one from a new run. Although I havent run his product I feel confident to use it should for any reason my own 948 should fail. Robin's use a CNC base, a deep groove ball bearing topped with a titanium faceplate. He can be found on eBay.

Roller clutch release bearings can be considered expensive but you are buying into longevity. Some of the stories I hear, from people seeking mine, are of modern carbon release bearings failing within hundreds, not thousands, of miles. If you have to pay someone to change the CRB then that can be truly expensive. If you do it yourself it can be a chore second time around.

The original carbon release bearing stood the test of time and if a NOS can be found may give miles of service it is those made in latter years that seem to fail so fast.





Alan Anstead

Can Alan say why roller clutch bearings have such a poor reputation on the MGB? I have understood that it is because they wear when they run off centre. Don't you need a tube guide over the first motion shaft to make it run true?
Mike Howlett

Thanks everyone. I'm thinking the ones on eBay are not from Alan as whoever is selling them also seem to sell bearings for the 948 and 1098
aj robinson

Mike

I have no idea why roller release bearings may have an apparent poor reputation on MGBs.

John Twist of University Motors in Texas says, on one of his You-tube turorials, that they dont work on MGAs. This has led some to decry them for all applications.

In U.K. Peter May has supplied roller release bearings for many years. The Peter May roller is mounted on an early Sprite Mk1 type casting. Using a tall bearing / mount it requires the pressure pad to be removed from the diaphragm.
Being tall / heavy it has a tendency to droop however I have fitted one, that has several years service, when doing a type 9 Sierra gearbox conversion, to a 1275 where the bearing is supported by the guide tube over the first motion shaft.
I have suggested to a garage, and just this week, a private owner that they use a Peter May bearing on their Frontline supplied T9 conversions where it appears that the roller release bearings supplied are not tall enough, having a diaphragm with pressure pad femoved, to allow depression of the clutch cover.
The garage, once I explained what they had to overcome, having a small machine shop extended the roller release supplied. The private owner is, apparently, going to refer back to Frontline.

I use one of my own release bearings, on my own T9 converted Sebring Rep, without the guide tube in place, over the first motion shaft, as I use a QH diaphragm with the pressure pad retained. The QH diaphragm cover pressure pad, unlike most other brands, allows the T9 first motion shaft to pass through.
There was a weakness with the QH pressure pad in that they parted from their retaining ring but that was easily solved by the application of a few tack welds.QH covers are not easy to come by these days.

I dont use eBay. I get asked to make mine mainly by 'word of mouth' and mentions in Masc Magazine or Fb pages.
Alan Anstead

Alan, I expect you know of Paul Hunt's website MGB-Stuff. If you look at this page http://mgb-stuff.org.uk/clutchr3a.htm#5 and scroll down you will see photos of the smashed release bearing that Paul found on his car, and below that the destruction caused to the pressure plate ring too. Further down you can see how the release bearing is nowhere near concentric with the first motion shaft. Naturally enough Paul doesn't think much of roller bearings on the MGB!
Mike Howlett

Mick

I have had a look. Why blame the roller release? Blame the yoke being so far off. Blame who-ever fitted the release bearing with so much offset.

The release bearing that I use can be used with some offset but there are limits.

Whilst there are always detractors roller release bearings have proven themselves on Sprites, Midgets and derivatives over many years.

Alan Anstead

Well, the carbon release is capable of handling the concentricity (or lack of) due to the arc through which the fork moves but it's best to ensure that it is as concentric as possible in all other planes. It should also be truly concentric just after the point of contact so that when the bearing moves forward to release the clutch plate it is, or near a possible, concentric. The MGB one shown in that link was clearly miles out.
Also, MGAs and 948 and 1098 Spridgets have different pressure plates that use 3 levers which release the spring pressure. As these levers, and fulcrum points of said levers, wear they can cause the levers to shimmy when operated which can make them out of concentric every time you press the clutch pedal. This would be certain death to a ball type release bearing.
Rob
MG Moneypit

Rob
You have been with me (Daks over Normandy Tour ) when I used my 948 (ish) Frogeye using a deep groove ball bearing, bronze faced, CRB. I am but a few weeks returned from France and it is still performing well four years, and many miles, later.

I suspect the arguements will continue for years as they do re Silicone Fluid, that I also use.

Alan Anstead

The ebay item is being sold by a captain robin. Same chap Alan?

Concentricity is more critical if running on the fingers of a clutch cover. Retaining the thrust pad on the cover, allows the release bearing to cope with with a bit of offset at the end of the arc, but it also reduces the amount the bearing has to travel, which reduces the offset. Alan's are also 'shallow', less weight, way less 'droop'.

If I needed a 1275 roller release, I'd buy one from Alan.

anamnesis

Alan, I'm sure your bearing is fine - it has been proved in many cars over many miles. Pity you don't make a similar one for the MGB! I shall stick to carbon for my MGB rebuild.
Mike Howlett

Does this fit an mgb Mike?

NOS.

QH CC15 Carbon Clutch Release Bearing Austin Morris MG

https://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=233900676670&category=262242&pm=1&ds=0&t=1638526677302&cspheader=1


https://www.ebay.co.uk/itm/233900676670




anamnesis

It might Anam. There are some B-series emgines there, but they would all be 3-main bearing engines with 3-synchro gearboxes. Whether that makes a difference, who knows, but mine is a 5-mains unit with a 4-synchro box. I have bought a new carbon bearing from one of the usual suppliers that I'm sure will fit.
Mike Howlett

But will it last? Time, alone, will tell!
Alan Anstead

Well, the last time I owned this car (15 years ago) I used it for 12 years as my everyday transport, going to work daily, and for MG events, some hundreds of miles from home, and I never changed the carbon bearing in all that time.
Mike Howlett

Mike
I have owned my Frogeye for 52 years. The carbon thrust release bearing has proven itself over the years on many makes and models.
Problems only arose, with its longevity, in recent years which some suggest may be a change in the type / manufacture of the carbon.
Perhaps fit a NOS item for peace of mind?
Alan Anstead

I put a new 'usual suspect supplied' carbon bearing in my rebuilt engine in 2007. It lasted a few weeks, giving out, very noisily on Scotland Road, in Liverpool.
It's similar replacement lasted a few months before the engine and gearbox had to come out again. This time Peter May's roller release bearing was fitted and has given good service since.
Jeremy MkIII

That was when one brand of bearing was being produced in which the carbon was retained by a roll pin due to insufficient interference. Premature failure was inevitable, as stress concentrated around the pin and the carbon fell apart.
There are still a few out there, characterised by having a protective white plastic cover on the carbon.
Paul Walbran

"The private owner is, apparently, going to refer back to Frontline." - Tell him to save his time.
Nigel Atkins

Paul
As I mentioned above the CRB castings that had the roll pin are the most suitable for converting with a deep groove ball bearing. The picture shows such bored to accept, and fitted with, a deep groove ball bearing awaiting fitment of a bronze pressure pad / faceplate.

Nigel
Not a fan of Frontline?

Alan Anstead

This might be an alternative to the poor quality carbon CRBs currently available.

Heavy duty so should be quite durable.

http://www.spriteparts.com.au/shop/performance.html#Rollerclutchreleasebearing

I think (?) these are available for early cars.
Philip Sellen

Both my cars have roller release bearings. The newest build has one of Alans bearings onto a standard cover while the one that has been going strong for 15 years (well until the crank broke this year!) is the Frontline one onto a standard cover with no pad.

I think the Frontline setup (the old one I have anyway) is OK but everything has to be spot on to get it to be reliable. The moving pivot, bearing to input shaft cover, fork bush and pinch bolt all have to be setup to allow the bearing to slide nicely.

The exposed forks on my cover have worn a little over the years but are still ok where the curved part of the bearing sits.

I’m upgrading the clutch over the winter which will come with a Peter May bearing so I’ll be interested to see how it all goes together and how well it works.

Although Alans bearing has only done a thousand miles or so it is working perfectly and required no setting up, just fit and forget!
John Payne

The picture is of the bearing I use and the offset it can achieve as the bearing proper can move about on its mount.
Glad it is milder today, and the garage is warmer, as I am out there making a few more.

Alan Anstead

This thread was discussed between 01/12/2021 and 04/12/2021

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