My 1930 saloon, with 3 speed gearbox, developed an intermittent “chirrupy bird” type noise earlier this year from near the gearbox. I was convinced it was the gearbox and have replaced it with another. The noise stopped for a few hundred miles but returned and has become almost permanent. It is at its worst between 30 – 40 mph in top gear and is engine speed related. Moving the clutch pedal by hand when on the move has no effect on the noise. Could this be caused by a faulty clutch thrust bearing?

Any suggestions would be welcome.

Location: Bedfordshire

I had this problem with a knackered three speed clutch release bearing, you can try dripping thick sticky back axle oil into the oiler hole whilst the engine is running, this helped for some considerable time. The ultimate cure was another bearing however.

When I had this noise it was due to a taper pin that is inserted into the bearing operating arm (sorry do not know the correct name for this part) fouling on a clutch operating toggle lever. Shortening the pin cured the problem. Examination of the toggle lever should show the point of contact as a shiny mark.
Bryan

Location: Hertfordshire

I hate to say it, William but my experiences of this coincides with Ruairidh's - clutch release bearing on it's way out. You may get a temporary respite from a few drops of heavy oil, as R says but, when you have filled the oiler with the heavy oil, poke down a piece of stiff wire ( about 1mm to 1.5mm diameter) to clear a way for the oil through whatever crud it is that has a nasty habit of blocking the oiler tube.

IMHO the 3 speed clutch release arrangement is a dreadful design and, the new bearings are relatively rare and rather expensive (round the £100 mark).

Ian Mc.

Location: Shropshire

The 3 speed clutch release bearing is a very large ball thrust bearing RHP XLT 2 5/8" , SKF O 21.

We are searching old stock bearings for some now, but they are very uncommon. Last ones we had were priced at A$296 (£180)

Being so large and only loaded infrequently they last well, but are always turning as discussed elsewhere so finally can fail, especially as they are difficult to lubricate.

Tony.

Location: Melbourne, Australia

Location: Shropshire

well done ian,

reading this thread and thought it took some time to get to davids site.

the original bearings are now obsolite,and have been for many years.

now being made in special batches.if david still has them in stock you should all be buying them.

i`m sure the price will feel expensive at first.but thats what happens when they have to be made to order.

(still much cheaper than australia though).

Thanks. I would have thought that not enough demand to make a special run - but there you are

Being offered some chinese bearings but they are generally not good quality

We are still looking for 'old stock' having found a selection of original crankshaft roller bearings recently.

Tony.

Location: Melbourne, Australia

The following is not an easy road to follow however life was never meant to be easy!! Especially in the antipodes.
There is a bearing that can be used but to do so requires a modicum of machining to the bearing housing and bearing.

The bearing I refer to is a 51113 thrust bearing.

However, despite the catalogue stating the inner diameter is 65mm it actually measures 67.3mm being the correct diameter for the bearing housing. The OD is fine.
The other noncompliant dim is the thickness of this bearing as it thicker by about .222” (5.6mm)

This can be overcome by leaving the sheet metal cover out and machining the step in the clutch lever retaining cup deeper.
If this not acceptable surface grind the bearing faces to thickness (remove .8mm, 20tho) and machine 1.5mm (062tho) from the back of the bearing housing, all should assemble as the original.

Doug Baker

Location: Scarborough Western Australia

I love Doug's solution to avoid an expensive one off.

However is Mac Bonar's solution the sensible option for most?

Charles

Location: Shropshire

If you look closely, Charles, you will see that whilst the 3 speed one is new, the 4 speed one is shaded in grey on David's list which means used.
I can find no-one listing new 4 speed bearings - last time I checked Seven Workshop were OOS of both versions; but, it was a while ago so the situation there may have changed.

Ian Mc.

Location: Shropshire

Necessity is the mother of invention, and we in Perth WA are a five hour flight to Melbourne where thankfully the majority of the Australian spares are sourced.

It was not my intent to suggest the treasured suppliers are expensive simply to offer what lengths we in isolation have to go too in keeping our little cars on the road. Basically we do with what we have available to us, it is this ingenuity I was sharing. As I stated in my opening sentence to follow my lead with this matter was a hard road.

Tony also stated he was endeavoring to find a supply and so far to no avail. With little prospects of ever finding a bearing in Oz I would modify something to keep my car on the road if it was reliable to do so.
I also read the bearings are made in batches, if there were no bearings available between batches this may render the car off the road, I do not see as an option.

Regards,

Location: Scarborough Western Australia

I had an occasional squeak from my old bearing, I took it to bits and found everything completely buggered.

A new one from David it was, and it now gets a regular dollop of prewarmed 1000 grade tallowed steam cylinder oil which is proper hairy arsed sticky.

Job done.

Ive since been buying the complete bearing assemblies as and when I see them priced nicley. I have now about 5 usable ones in stock, and some more jiggred ones.

I think they will last me before I have to convert to the 4 speed ones.

Tony, my Chummy is currently running (well) on one of your most reasonably priced 4 speed good originals after eating 2 x 3speed S/H bearings in under 10,000 miles - despite almost fanatical attention to lubrication but, I do worry a little where I will replace it as/when it's knackered. I don't think that the bearing is likely to be available from BML!!

Ian Mc.

Location: Shropshire

hi ian,
you are indeed a wise man.

when you bought that race i had just bought out a supplier of parts from london.

there were several 4 speed and 3 speed thrusts in what i bought,i then checked through my own stocks,and i must have had a tray of 20 good ones.

the tray is now empty.

but i have had several scruffy gearboxes in since,so its high time i went on the hunt to see if i have any good thrusts amongst them.

tony

I don't know if this is any help, but might this one from Consolidated bearings do the trick?

http://www.consbrgs.com/page.taf?detail=316_1_6

Looks pretty straightforward to me, or have I missed something?

Location: Near Bicester

Very good, Ivor. That is indeed similar to 3 speed release bearing but not correct.I've just run the calipers over a NOS one on my shelf.

The dw is about right but we are looking for a Dg of 3.500", and H of 0.500"

Sorry, nearly but not quite right.

Ian Mc.

Location: Shropshire

Thank you Ruairidh.

Thank you Bryan N.

Thank you Ian Mc.

Thank you Tony P. in Aus.

Thank you again Ian Mc. Availability noted.

Thank you Doug B. in W. Aus.

Thank you Charles P. for the link - Mac's solution does appeal to me and I think I will do it.

Many thanks to everyone else for all your suggestions and information.

I will let you know how I get on - the engine came out yesterday!


Thanks, William, in Bedfordshire.

Location: Bedfordshire

So no cigar then Ian?

It was worth a shot!

Location: Near Bicester

Sorry Ivor, nice try though worth at least a Park Drive!!

Ian Mc.

Location: Shropshire

This may not help but it pays to go to our austin seven rally at Beulieu every year as last year on the 750 club stand I picked up a brand new unused 3 bearing clutch bearing for £20 no one new what it was But I did!!

so go to these national rallies!

Chris

My 1950's Edmunds, Walker & Co. Ltd catalogue doesn't list the 3 speed clutch withdrawal thrust, but does give the spec for the 4 speed thrust as:

Hoffmann N1307 or R&M 1/XLJT2·3/8

Dw = 3·7/16"

dw = 2·3/8"

H = 11/16"

Jeff

Location: Almost but not quite the far North East of England

Ian,

I think you are right - the three speed thrust bearing is an RHP XLT 2 5/8" which is lighter bearing than the SKF O21 I mentioned, which has dimensions bore 2 2/8" x OD 3 27/32" X depth 1", similar to the one Ivor noted although this had depth 3/4".

SKF O 21 is RHP LT 2 5/8" (no X)

Tony

Location: Melbourne, Australia

Location: Shropshire

Ian and Jeff,

Yes - another special bearing- Hoffman N1307 - RHP 1XLT 2 3/8 is a steep angle angular contact bearing (probably specially made for Austin) and am fairly sure there is no SKF equivalent.

Those dimensions sound correct.

I think these are quite rare as noted..

Tony.

Location: Melbourne, Australia

When they designed the little blighters, it would never occur to them that in 80+ years time there would be a whole bunch of strange individuals agonising over where the next clutch release bearing was going to come from!!

Funny old world. I'm eternally grateful that veteran cars are way beyond my financial capabilities. We Sevenists are extraordinarily well served in the spares dept.

Ian Mc.

Location: Shropshire

Location: Near Bicester

Am I just lucky or so deaf that I can't hear the race rattling about? I haven't had any failed clutch thrust bearings (only wear in the 3-speed toggle lever carrier)in the last 48 years of A7 motoring. I didn't realise it was likely to be a problem. I think the RN saloon has still got its original race although my dad stopped using the car in 1983 and I now use the car fitted with a 4 speed box with a different race.
In my 1937 East London Rubber Company catalogue the Austin Seven R&M clutch thrust bearing is 18 shillings for 1922-32 and 28 shillings and 9 pence for 1932 to 1937.That's a big difference! I could give them a ring and see if they have any left (Tel.4321 Bishopsgate)

Location: Sheffield

Location: Nr. Selby, North Yorkshire

Ian,

For the three speed bearing you measured-

"The dw is about right but we are looking for a Dg of 3.500", and H of 0.500""

Are you sure the Outside Diameter is only 3 1/2" - With a 2 5/8" bore this only leaves 7/16" for the track width?

Tony.

Location: Melbourne, Australia

charles you are truely lucky if the bearing hasn`t got any rust spots on the bearings by now even sitting in crud.

often these bearings can feel good but you are only turning them at finger speed.

a little tip i probably shouldn`t give away.

if you clean it out with paraphin etc.

blow the excess off with an air hose the bearing should start to freely rotate.let it get up to full speed.and see if it is still smooth.

you will feel if there are rust spots on the bearings.

if you want something to compare to wash out a new large wheel bearing.and do the same test.

if the thrust bearing does vibrate,the ball bearings are still available.you can always strip and rebuild it.

Location: Shropshire

Ian,

Thanks very much for checking, greatly appreciated. I have just been advised by a local bearing supplier that the correct designation for this Austin 7 three speed thrust bearing is HOFFMAN/R&M N2400.

Which probably explains why an earlier order for R&M XLT 2 5/8 gave the wrong bearing !!!

I don't know where our spares people got the XLT number from. Slowly getting there

Now we have to find some N2400

Tony.

Location: Melbourne, Australia

Dear all, following all the valuable advice you gave me i decided to "grab the bull by the horns" so to speak, and remove the clutch thrust bearing with a view to replacing it with a 4 speed device. However, before progressing too far I telephoned the very nice and helpful people at The Seven Workshop about spares and spoke to the very knowleable and helpful Dave Williams. He told me that from my description of the noise he thought it more likely that it was caused by a "dry" under greased Carden joint on the prop shaft. I already had the engine out so I dismantled and examine the clutch thrust bearing first. The oil tube was quite clear, there was plenty of oil about and it looked in good condition (see picture below if I can make Photobucket work) I tested it on a wood baffle board (stairs) as per Dave Williams' advice and it sounded not too bad! Next I removed the prop shaft complete and stripped it down - one side's pin and block were very dry and badly worn despite being new last year! Again, see pictures!! I have greased regularly with moly Lithium grease but obviously not enough! Also, it looks like it needs a more fluid grease? Perhaps grease?oil mixture? I do not know yet if it will cure the Canary but I' almost sure it will. Many, many thanks are due to Dave williams and The Seven Workshop for their expert advice.

William.

Hi William, Well, I'm glad you found the cause, even if our corporate experience sent you off on a red herring as it were!

That carden joint worries me, unless the photo is deceiving me, it is almost inconceivable that one side of the joint could wear through the block like that in only a year. Is it possible that there is some misalignment within the joint itself? A bent pin or something similar?

More photos would be interesting and please do share your eventual findings with the forum.

Ian Mc.

Location: Shropshire

William, I agree with Ian, I've never in my life seen a Carden joint wear like that in a year...if the pin isn't bent, is there a lot of slack in the yoke?

Location: Near Bicester

Has it jammed against a worn part of the Carden housing/pot? What does the inside of it look like, are there any steps/grooves?

It is very important that the back end of the shaft is a perfect sphere,and that the centre of the carden housing is a perfect cylinder ,or you are quite likley to end up with what you seem to have got.

Location: Wessex

As noted by others I have never seen wear like this especially at twelve months?

I thought the carden blocks were very hard and would expect the pot to wear well before this anyway.

Are the replacement blocks properly hardened? I have generally re used old original blocks.

Universal joints sometimes have a problem with too little angular movement during operation so the lubricant isn't spread around - not a problem I would have thought with a standard Austin 7 assembly

Tony.

Location: Melbourne, Australia

Thank you Ian Mc for your comments I have uploaded more pics.

Thank you Ruarirdh for your comments I will look carefully.

Thank you Ian Dunford for telling me about the shere and the perfect cyclinder - I will look carefully.

Thank you Tony Press I will check if the damaged items were hardened.

Now, I have to tell you I was quite shocked at what I saw when I dismantled it. I take great care to look after my car, especially the lubrication. However, looking at my records I see it has been 3 years and 8000 miles since I fitted new blocks and pin. At the same time I fitted the Mini type rubber boot which you will see from the picture has rubbed the tunnel due to me not realising it should be shortened! You will see in the other pic the grease loss on the side of the battery box because of this. However, no excuse I obviously under-greased this item! In addition I used a Wanner grease gun wich, now I have checked, delivers only a small amount per lever operation and I greased from the underside of the car and did not grease from the top using the aperture in the tunnel wich could have affected where the grease got to. For futher interest please see pictures below.

Thanks to everyone, William.

William.
Thank you for posting the extra photos.
In the third photo, the wear on the pin carrying the worn block, adjacent to the shaft is saying to me that, for whatever reason, that block hasn't been running "square". Something, maybe damage inside the carden pot, has forced it to run canted at an angle causing the wear to one side of the pin and the hole to wear in the opposite side of the block??

I may be wrong but, it doesn't look like a simple case of insufficient lubrication to me. I will be interested to see what others think.

Ian Mc.

Location: Shropshire

William

The grease looks very like the grease on my RL floor!

Presumably the wear is on the thrust face of that bad block when going forward?

Other than the inside of the pot having some defect that wore that block, the only thing I can see is that the block was softer than the other, but once it wore a bit it kept getting worse.

The only other thing I can think of is that I wonder if your prop shaft is the correct length?, when I built my car (RL) out of spares, I chanced upon one too short, one still to short but longer, one the correct length (off fathers box of bits chummy!) and one far too long.

Of the ones that were too short, the longer of the two looked like it may have worked, but the blocks were not always fully in the pot. I think this sort of defect would have resulted, but I would have expected it to be on both sides.

I've just gone through the process again with a prop, father is now rebuilding the chummy, I took a chance on one from a guy I bumped into in shrewsbury, and it paid off as it was the right length.

William. From what I can see in the pictures it looks as if a lot of heat has been generated also. Anything other than a 'straight line' from propshaft to torque tube increases the work of the pin and blocks in the joint.
Just a thought.... Do you have any sort of non standard rear springs? The reason I ask this is because I had a very similar problem caused by non standard springs which made the car sit too high at the rear end. The result of this was as described above - too acute an angle was wearing out the whole mechanism faster than I could replace it and also generating the chirruping sound you have described as the lubricant was being dispersed by the heat.
I also advise reducing the rubber boot in size.

Location: Farnham