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MG Midget and Sprite Technical - Ford 5-speed clutch diaghpram wear

Good evening Gentlemen!
Having the emngine out to renew timing cover seal and rear seal, I notice some wear in the diaghpram spring, where the release bearing runs.
The gearbox and clutch has only been running for approx. 3500 miles the past season.
When turning the release bearing by hand I don't notice any malfunctions.
I will post a photo of the bearing in the next thread.
I will post a photo of the drained gearbox oil too. It has a red appearance, I think rust. It is not as visible on the photo as in real, though. The Castrol l I have used is colorless and I am very surpriced, that the oil is that red, considering that Ford developed a gearbox filled with synthetic oil for the gearbox lifetime.
What do you "Ford 5-speeders" think about that?
Jan



Jan Kruber

Bearing


Jan Kruber

Oil


Jan Kruber

A bit more info required for the oil -

a) when you got the g/box was it completely dry of oil or filled with what?

b) have you flush-cleaned the g/box when you got it or before putting the Castrol in?

c) did you drain or siphon the oil out?

d) did you drain or siphon with the g/box hot or cold?

e) what quantity of Castrol did you get into the g/box?

e) what quantity of oil (litres) did you manage to get out at each drain/siphon?

Basically I'm just wondering if the red colour is from the residue of previous oil or perhaps additives that might have been put in. Depending on the answers from above it might be that you just need to flush clean the internals the internals of the g/box.

On all the hot siphons of my T9 and various makes and models of g/box oils (that had been in a relatively short time) the oil that comes out is darker than when it went it. I've never bothered to clean the internals or flush as the oil changes have unfortunately been so frequent and I don't have a drain plug.
Nigel Atkins

If it’s newly rebuilt it could be some form of build lube they have used. For example the first oil change after I’ve rebuilt an engine is always a strange colour due to the graphogen and red cam lube I use.

I’ve moved away from using Castrol in my type 9 as BGH don’t recommend it. I think I used Comma last change but can check if you like.

The release bearing looks fairly normal to me. The forks on the diaphragm have worn a little on mine but nothing major. I take it yours is just a midget cover with the carbon release bearing pad removed? Mine is one of those (Frontline) and has lasted well over 10000 miles of 100bhp abuse.

Keep changing the oil and see how it is after a couple of changes. A nasty job though!!!
John Payne

BGH recommend Comma as it's the same Ford spec number but the Ford number was a general number that transferred through a few different oils, Ford just want you to buy oil (various over the years) in their Ford labelled bottles.

Some trades tend to be very conservative and traditional in their outlook and have to allow for the very wide range of their customers and their customers' use of their products so will keep things very simple and stay with a known product with decades of history rather than risk further research.

There's a long thread somewhere in the Archives where L and I went through the various numbers and oils with the Ford recommended number and it included a GL5 from Q8.

As always it's each to their own, many use the Comma and find it to be fine but the Castrol is better for changes in colder weather so even more suited to places like Cumbria, Scotland and Denmark.

I'm thinking with the red, possibly residue of ATF used as a cleaning-flush or for storage use or used to ease cold or poorer shifts. ATF was often used decades back in manual boxes when perhaps the more suitable oils weren't available or less well known about.
Nigel Atkins

All of the Type 9 boxes that I have had from scrapyard cars, 8 or 9 in total, have had a red oil in them. I presume they were all still using the original factory oil. It wouldn't take much at all of that stuff to be lurking in bearings or oilways to contaminate and colour a clear Castrol oil and give it a reddish hue.
GuyW

Nigel
a) The gearbox should be refurbished and looked very nice. It was delivered dry
b) Not relevant
c) I emptied the gearbox with a siphon
d) Cold
e) could only catch 1 liter

Photo of the gearbox when received nearly one year ago addded


Jan Kruber

The oil I have used, photo


Jan Kruber

John
Maybe I should know, but I'm a novice, what is BGH.....?
My gearbox supplier recommended Comma oil, but since it's not awailable in Denmark he approved that I used Castrol, as long it was a GL4 oil.
I'm conserned that after only 3500 miles theres missing 2 to 3/10 of a millimeter of spring material.
After a few more seasons the springs will be worn that much that they will bend ot break, I believe.
Another thing, why is there all that red dust all over, looks like rust, but I never have been out in rain or even sprayed the car with water.

The photo show a Frontline clutch cover, looks like mine.




Jan Kruber

Guy
I will ask the supplier if he has added something red colored when assembling the gearbox.
Jan Kruber

Jan,it does depend on how well the box was cleaned out internally before assembly. If it wasn't fully stripped with every bearing being either replaced with new, or rinsed out and re-oiled then some of the original red coloured Ford oil might still be in there when you refilled it. I don't think it would take more than a few cc's to colour the Castrol.

The other possibility, as perhaps you suggest, is that the bearings were greased to protect them in the dry stored box and a coloured grease was used.

As for the wear like that on the clutch diaphragm 'fingers', from recollection mine were similarly worn on my original T9 installation. I then changed to my concentric slave system in which the release bearing is in constant contact with the clutch springs. But as such, the bearing rotates continually in contact with the clutch and the movement is all taken by the bearing itself, which is of course designed to do just this. That is one benefit, the release bearing isn't continually spinning up from zero to maybe 5,000rpm and down again, each time you change gear, with this differential resulting in wear on the clutch fingers (or indeed on the pressure pad, for those that reain them)
GuyW

I'm inclined to think the diaphragm finger wear would be down to the bearing not being concentric and so the surfaces will rub against one another as they rotate and the fork articulates, an unfortunate defect of using the standard fork arrangement. Even the OE Ford arm provided concentric operation due to the guide tube.
David Billington

Good point David
So Jan--If your t/out bearing isn't a nice slidey fit on the tube you need to get one that is and a 'light' smear of grease on the contact area with the diaphram wouldn't hurt just to help stop any rusting there
willy
William Revit

Jan,
Guy once again makes a very good point and cleared up something I wasn't sure/forgotten about, the Ford oil being red in colour. I've never seen it fresh in the bottle but probably emptied it out of a 25 year old Capri gearbox 12 years ago as it was red. The red is only a dye so don't worry about it if the oil is the cause, it could just as easily be a blue or purple dye.

BGH - BGH Geartech, gearbox specialist, PDF articles were included in what crashed your email along with loads more info.

That Castrol oil will do you good stick with it, good oil anyway and particular good for cold weather changes, proven by a few users on here including me (although I now use, close your eyes, a GL5, Millers CRX).

1 litre is a fair amount of oil to siphon out cold if your gearbox only holds 1.25 litres (higher filler/level hole) but obviously not so much if it holds 1.9 litres (lower filler/level hole). Obviously the more existing oil that is got out at each change means the more fresh oil is put back in and the fresh oil is less diluted by the residue of existing oil.

As for the bearing colour, IIRC mine was the same sort of colour, not as much as yours though and my car was most definitely used in the rain as I often stray into Leicestershire and am in England anyway.
Nigel Atkins

Is the 'rust' colour on the clutch cover not just dust from the clutch disc?
GuyW

I was wondering about clutch dust too.
Jan, as you have the gearbox out already you have the easy opportunity to take off the top cover and give the insides a really good clean out to set your mind at rest. Also you could easily drill and tap the case for a drain plug to make your life easier for future oil changes.
Just a thought...
Greybeard

Jan,
sorry, I should have looked more, on second look that Castrol's not exactly the one I was referring to (I should have turned my head).

The photo you put up is for Syntrans Transaxle for transaxles.

The one I refer to is Syntrans Multivehicle for manual transmission (gearbox).

They are very similar but not exactly the same, I can't imagine there would be any harm at all done by using the Transaxle.

I thought I might have included my T9 gearbox oil change notes to you before but if not I can send them on if you want, all non-technical stuff but does include hyperlink to Castrol Multivehicle.

Transaxle - https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/7E3D454FD5E9B7EE802582B80030D8B8/$File/BPXE-9ZWGML.pdf

Multivehicle - https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/3A2AC3E19A7AEE6D80257E83003062B0/$File/BPXE-9ZWFHN.pdf

Below is a photo of the Castrol Syntrans Multivehicle 75W-90 (Fully Synthetic MTF) I meant and referred to in my earlier posts.



Nigel Atkins

Guy, you are right again!
I asked my supplier and he replied very adequately as usual:
With regard to the oil colour this normal we use a moly grease to assemble our gearboxes as this heats up with the transmission this will mix with the oil and darken the colour gears are also coated with
Manganese phosphate this is a manufactures coating on O.E spec gears and again will mix with the oil So I would not worry too much about this.




Jan Kruber

David / William
How much play between the guide tube and the bearing is acceptable?
Jan Kruber

Guy / Grey
There was a lot of red rust dust on the friction plate core and the cover. I dont think it is fristion plate material. First the material is black / brown. Second wear is allmost none.
I think it is from the material grinded away from the diaghpram and perhaps the bearing too.
I will take the parts to the local brake and clutch machineshop and ask if they have experienced this on parts that new. Perhaps they hae an input to that.
Thrid, I wonder why I do not see any metal debris, only this red powder / dust.
Fourth, I wonder why it is all that red when not having been in cintact with water. The cover, the flywheel and every other bare metal parts on my car has no rust to mention.... ??
Jan Kruber

Grey
My gearbox supplier, First Motion, very strongly advised me against having made a drain plug when I asked him if he would install it when preparing my gearbox. I just listen to recommendations.........
Jan Kruber

Nigel
I will have to order gearbox oil, since I do not have enough on the shelf. Do you recommend that I buy the "syntrans multivehicle" then in stead of "syntrans transaxle"?
I want the best!
Jan Kruber

Jan,
probably the best that your builder would approve of as a GL4 is the Syntrans Multivehicle.

You have many choices as to what you can or want to do.

If you have enough Syntrans Transaxle you might want to put it in the box and use it as a flush and do a hot siphon/drain/empty and refill with fresh Syntrans Multivehicle.

You could ignore the stock of Syntrans Transaxle and siphon/drain/empty out as much of the existing residue as you can and refill with fresh Syntrans Multivehicle.

Or you could just top up what's already in the box with fresh Syntrans Multivehicle.

If you're able and want to you could fit a drain plug and do a full drain, flush partial refill with Syntrans Transaxle, hot full drain and final refill with Syntrans Multivehicle.

Photo below is Arie's box with plug fitted from BGH Geartech (I wish mine looked like that when it was provided and fitted and had a drain plug).




Nigel Atkins

Jan I fitted a drain plug into the main part of the gearbox casing. There is a D shaped flat area on the bottom of the box which almost looks like it was made for this purpose. And the cast iron is thick enough to cut a good thread into for a decent sized plug. Adding a drain plug is quite common and I have never heard of anyone having any problems.
GuyW

Have bben thinking, what if the release bearing in fact is malfunctioning?
Does any of you know which type is it?
You can see it here:
https://www.ebay.co.uk/itm/FORD-TYPE-9-5-SPEED-GEARBOX-MOUNTING-KIT-1275-MG-MIDGET-AND-OTHERS-/113482303807
Jan Kruber

Guy,

The D shaped depression holds a circular magnet to trap steel particles. All I have seen have a hole in the middle so you would want to drill in the centre of the D.
David Billington

That's right David. I drilled in the centre, but then later removed the magnet anyway, and used a drain plug with a magnet built into the end of it. That way when I change the oil I remove and clean off any ferrous debris rather than it being retained inside the gearbox, albeit trapped by the doughnut magnet.
GuyW

I just noticed, that the link I inserted above doesn't really show anything.
Here is a picture of the bearing.
Inner diameter 38mm and the bearing is 19mm deep. It is marked 3294 D1612.
What vehicle did that come from?



Jan Kruber

and one more from the other side


Jan Kruber

Jan, as you know I don't use this arrangement, but I had understood that the usual advice is to use a flat faced release bearing if it presses onto a flat pad. But if the bearing bears directly onto the clutch cover 'fingers', the the contact surface of the bearing should be rounded. Yours looks pretty flat, other than a slight rounding of the edges.

If you think about how the bearing contacts the fingers as it moves forwards, they will pivot over the outer edge of the bearing, rather than a smooth transition as would happen with a rounded surface. This may be what is accentuating the wear on those fingers.

Maybe, with the gearbox out, you should think about changing to a modern concentric slave system. Mine was a DIY effort, but kits are available designed specifically for the T9 box.

http://tinyurl.com/ybm9zxt8
and although this is for a T5 Cosworth box, it shows the arrangement:
http://tinyurl.com/y9j47sl9
GuyW

Jan's bearing doesn't look flat to me, all the flat release bearings I've had are properly flat across the full face and are designed to work against diaphragm finger with curved ends
David Billington

Looks very similar to this (photo) in which case it is a Ford release bearing. Ignore my mounting with spigots as it is adapted for 1098 A-Series.


Alan Anstead

That's it Alan. That's what I meant by flat - it only has a radius on the outer edge. There will still be a point at which the fingers suddenly transition from contact with the flat surface, and then lifting as it goes over onto the outer radiused edge.
GuyW

Guy
It's the first picture that show the surface pressing against the fingers, is pretty much rounded, I think.

I was talking with two experienced (=older) mechanics today. They were convinced, that the "mishap" is generated because the bearing is running against tne fingers all the time. They recommended me to cut a bite off the slave pushrod, just enough so that the bearing is not touching the fingers when the clutch isn't engaged.
I can follow their thoughts, I have to make some distance between the bearing and the fingers.
I feel pretty convinced, because I notice some wear on the fork pivot bracket, but only in one specific spot, and thats where the pivot bolt is resting. This wear spot is for sure generated, because the pivot bolt is resting here under pressure all the time, except when the clutch is engaged. I hope you understand it, this is exceeding my English skills :-)
Shortning the push rod seems as an easy fit then, what do you guys think about that?
Jan Kruber

Maybe I am misinterpreting the photo Jan.

What is it that pushes the slave cylinder back up the bore when you take your foot off the pedal? And what determines how far back it goes, so as to give the clearance at the release bearing?
GuyW

shortening the pushrod may not be the answer, just as lengthening it doesn't fix the 'bite point too near the floor' problem. Unless you have a mis-match of clutch master and slave cylinder bore sizes the movement on a full pedal stroke is much more than is needed to disengage the clutch and when the pedal comes up to the top it should pull the thrust bearing away from the pressure plate to leave a running clearance. If it isn't, then you can fit a return spring on the release arm outside the gearbox to remedy the situation, I seem to remember Morris Minors had this arrangement?
David Smith

Yes, MMs have a spring attached to the end of the clutch arm that pulls it clear.
My question was to clarify what does pull the piston clear as the only obvious force is the clutch springs, acting through the lever and push rod but that alone wouldn't provide clearance.

So Jan, do you have the pedal pull-off springs fitted in the footwell?
GuyW

the spring inside the slave cylinder 'should' push the piston to the flexihose end of the bore if there's no pedal pressure. However the springs are not very strong and I've often wondered if new cylinders are too stiff for the spring to do its job. Also I've wondered whether different types of fluid have markedly different lubricating properties?
David Smith

Isn’t the spring behind the piston, so it will be pushing it the other way?
Dave O'Neill 2

Yes, the spring is behind the piston, maintaining contact with the piston seal.

Take your foot off the pedal and the clutch springs push back on the bearing, lever and the pushrod, pushing the piston back up the bore and forcing fluid back through the pipework to the mastercylinder. But without any other assistance, surely that's as far as it goes.

The only additional force I can think of is either a degree of wobble / vibration from the spinning clutch which might nudge the release bearing clear. Or, as David commented, suction on the hydraulics caused by the pedal being released, but this must need something to lift the pedal that but extra. Which is why I asked Jan if he had the pedal release springs fitted. Although at a different point in the overall system, a spring there would perform the same function as the MM spring attached to the lever arm end.
GuyW

Guy
I have not a return spring on the slave cylinder.
I seem to remember that when not engaging the clutch, it is not possible to press the oushrod further back by hand.
Springs in the footwell, well, I think so, will have to check.
David
I think the match between the master and slave was balanced well when working in the old ribcase.
Jan Kruber

Jan,

Regarding your question about bearing clearance on the guide tube, I've just measured one of my type 9s and the guide tube is 33.65mm OD and the release bearing is 34mm ID although a bit difficult to measure as the plastic bearing mount which runs on the guide tube is ribbed internally. It's a totally flat faced release see image. Interestingly the release bearing can move about a bit, approx 1mm each way on the carrier, so may allow for a bit of self alignment, it isn't loose but doesn't require more than heavy finger pressure to shift. This bearing is intended for use with a diaphragm spring with curved inner end to the fingers unlike yours which should have a radiused face to suit flat fingers.



David Billington

To clarify this is the type of cover plate that my previous post image is to suit https://caterhamparts.co.uk/clutch-parts/71-clutch-cover-k-series-ford-crossflow.html . I used a similar bearing with my 4 speed Ford gearbox conversion and retained the graphite pad release face on the clutch cover but used a Ford clutch cable and release arm and modified the master cylinder box to suit cable release so the bearing was concentric.
David Billington

The only problem with fitting a return spring to the slave cylinder is that you would need to make sure that it didn’t pull the release lever too far away, meaning that when you press the pedal, you don’t get enough movement to fully disengage the clutch.

The Morris Minor has a mechanical linkage, rather than hydraulic, and is adjusted to provide enough clearance, but not too much.
Dave O'Neill 2

David
Your guide tube outer diameter and the inner diameter of the bearing carrier is the same I can measure here: 34,00 and 33,60mm.
The bearing itselves without carrier has an ID of 38mm. Dept is 19,00mm.
If could find a bearing not so deep OR having the carrier modified so that the bearing is placed deeper on the carrier, that might screate the nescessary gap.
When I assembled the lot a year ago I didn't know I had a "problem". Now I know it and what to take care for, I will find solution. It's brilliant with this board discussion and to discuss it with mechanical people I meet.

Dave
If a return spring is the solution I'm aware that there must be an end stop on the fork.
Jan Kruber

It's very odd. I have looked thoroughly on the www, the release bearing is impossible to find. It looks somewhat like the bearing for a Triumph Spitfire and others, but as long as I can not find the dimensions of those, I'm status quo. Some manufacturer makes the bearing I miss, but who?
The supplier of my conversion kit, (not the gearbox) want £125 !! for the bearing and carrier. He will not sell the bearing alone.
Peter May has a bearing on a carrier, that looks fairly much like the assembley I have here, at half the price as the above mentioned. He is promoting it as a roller bearing conversion. I wil contact him and ask for some dimensions.
BUT, why is it impossible to reveal the origin of the secret bearing?
I don't believe it is a bearing solely manufactured for a few Ford five speed conversions. It has to be a bearing allready excisting, that was choosen to the kit.
Inner diameter 38.00mm
Outer diameter 68.38mm this dimension is not critical
Hight 18.00mm This dimension can be less, (that would give more gap between clutch fingers and bearing)
Any input welcome
Jan
Image attached show the bearing and carrier from the side clutch side



Jan Kruber

This image show the gearbox side of the bearing and carrier


Jan Kruber


VKC3505 -- Toyota Diahatsu--? -16.5mm thick

http://www.0086parts.com/auto/product/clutchreleasebearing.pdf
William Revit

I think it looks like that used on the early Capri and similar age Fords see here https://www.ebay.co.uk/itm/ford-capri-mk1-1600-GT-clutch-fork-and-release-bearing/163501184271 also https://www.ebay.co.uk/itm/FORD-CAPRI-MK1-1300-1600-1600GT-OHV-NEW-CLUTCH-RELEASE-BEARING-1969-1974-JN125/273515681492 . Maybe the last one would be kind enough to measure it for you.
David Billington

How about https://www.burtonpower.com/clutch-release-brg-mk2-ford-cortina-lotus-mp315-hd3259.html
David Billington

If you are not successful with Burton try Simply Bearings. Their search engine will allow you to put your dimensions in and show various options.
Alan
Alan Anstead

Alan,

I knew they did some auto bearing but assumed they were wheel bearings, they actually do them for quite a diverse range of auto applications and even list 1 Borg & Beck carbon release bearing. https://simplybearings.co.uk/shop/p187773/Borg-&-Beck-HD1069-Carbon-Clutch-Release-Bearing/product_info.html?backstep=1 . Who has samples to identify if it suits any spridgets.
David Billington

David,
bear (no pun intended) in mind that B&B are part of First Line and IIRC (but check as I'm vague as usual) I think there were complaints on the B(?) forum about the bearings in the clutch kits (IIRC).
Nigel Atkins

Dave
I use Simply Bearings for some of the deep groove ball bearings that I use for clutch release bearings.
I find their service good and efficient.
Burton too are good as they are where I get the bearings for the 1275 release bearings that I make.

I should be on the Midget & Sprite stand at NEC for Practical Classics show if anyone wants to say "Hello".


Alan Anstead

This thread was discussed between 19/01/2019 and 27/01/2019

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