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MG Midget and Sprite Technical - Clutch slave cylinder

Hi

I am getting ready to replace my clutch slave cylinder (7/8" bore, 22A233, GSY110) for my 948cc Sprite MkII.

What are the correct mounting bolts (set screws) please - UNC, 3/8" diameter by 1" long? If so Minispares have them, https://www.minispares.com/product/Classic/Fasteners/Bolts/GFK5240.aspx?2101&ReturnUrl=/product/Classic/Clutch/Hydraulics/GSY110.aspx to or if not I will be trying Namrick.

I will be soaking the bolts with Plusgas for a few days first and modifying the slave cylinder top mount by cutting it into a slot (another Alan A tip - thanks!)

Any other tips please for changing this cylinder, including pushrod related etc?

Seems like genuine GSY110 are not that easily available. Somerford Mini, David Manners and LMS Litchfield look to have them in stock.

Cheers
Mike
M Wood

Mike,
Moss have it listed as both UNC & UNF but the number as SH506091. - IF - this is the correct part number then it shows on Paul's fastener list, and other suppliers, as (set screw, hex head,) UNF, 3/8" x 1 1/8". -
http://www.mgb-stuff.org.uk/partnos.htm

Although Paul's mgb-stuff is about Bs so much on it also relates to Spridgets and there's so much there to draw from.

Great news on the use of PlusGas, I'd suggest as the screws are soaking once a day you try to slightly tighten then loosen the nuts, well as much as you can.

All the tips, that I can't remember other than slotting, will be in the Archives but not my head.
Nigel Atkins

Not checked, but I would definitely expect it to be UNC thread into an alloy casting. And I do know that the standard bolts are longer than necessary which just adds to the tedium of tightening, one spanner flat at a time!
GuyW

Mike,
now having sight of the reprint of the factory parts catalogue (not to say that doesn't also have O&E) for the 1098cc it shows -
53K 152 Bolt cylinder to gearbox NLA

and for the washer -
LWZ 305 Washer spring

the washer comes out on the list Paul has (and elsewhere) as heavy, zinc, 5/16" but it looks like it's from use with older cars and an ordinary 5/16" spring washer will do (or perhaps a shakeproof).

Probably best to get your current bolts/screws out and see what they are and reuse them or if they're UNF perhaps a slightly shorter length with a point at the start.
Nigel Atkins

Deffo UNC, and I have a potfull! Mike, email me your address and I'll put a couple in the post to you pronto.
mgsmithy on yahoodotcodotuk
David Smith

For future accuracy does this mean the UNC are 3/8" x 1" then?
Nigel Atkins

Definitely 3/8” UNC. I would hazard a guess that it’s more like 1-1/2” long - 1” would barely get through the lug once it had a washer on it.

Also, a 5/16” washer won’t fit.
Dave O'Neill 2

I dug out my pot; the originals are 1 1/4" with a half inch plain shank. They can be shortened to 1" and still reach the inside of the bellhousing.
David Smith

Hi
I am in the process of renewing my slave as well but on a frogeye.
Yes slotting is a great tip for which I must thank the contributors on this forum.
If the Mk2 is anything like my frog, I would strongly recommend considering a remote bleeder. I found, access through that tiny aperture, even with the steering wheel removed, a real challenge. Especially as bleeding the clutch can be a long process.

A friend, who is an excellent mechanic, told me that my proposed set up for my remote bleeder (as recommended at the suppliers) was wrong as the flares on the extension hose need to be male to seal correctly. I didn't even know there was a difference!

Hope this is of some help.

By the way I bought my slave from mini spares GSY110MS.

Graham
Graham V

Hi all

Thanks again for very helpful advice and help.

David - yes please to a couple of your bolts - I'll email you. Many thanks.

Graham, thanks for the tips and info. Yes, the MkII is the same as the Frog. Where did you get your remote bleeder from please, as I have bought and installed one and am wondering if I have the same potential issue?

Cheers
Mike
M Wood

Mike
You should be ok I would think, as I didn't buy a "remote bleeder" as such. I simply bought a piece of 12 inch brake pipe with UNF fittings already in place at the ends, and a 3 way brake union to finish off at the end to bleed from (3 way but with one port permanently blocked with a bleed nipple, as it comes with a screw hole to fit more easily than a 2 way union).
Graham V

The correct brake pipe to use if setting up a remote breeder is the one that normally goes from the rear bulkhead to the brass connector on the top of the diff casing. It is often sold as the longest one of a set of 3 pipes for the rear hydraulics, but of course can be bought separately.

When bleeding the clutch, start by pushing the slave piston as far back up the bore as possible with some suitable prodding device and secure it there with a clamp. This reduces the volume of the fluid in the slave and ensures that there are no places for air bubbles to lurk away from the flow towards the bleed nipple.

Secondly jack up the right hand side of the car, ideally by about 9", but any amount helps. This raises the bleed nipple (or extension hose connection) to the highest point to let that last bit of air bubble out.
GuyW

I have used all methods and easy bleed but now an a vacuum device with uses compressed! air. It works better than any other method; quick and clean.

Flip




Flip Brühl

Here is a picture that shows why you have to jack the right hand side.


Flip Brühl

And make sure the bleed nipple is in the top, not the bottom hole as I read in this month's Mascot!
Peter Blockley

Thanks everyone.

The jacking up tip of one side for clutch slave bleeding seems to work well as I got the clutch back working after a replacement master cylinder. Slave cylinder to be replaced as required (probably soon as car has Been out of action for 6 years).

David - thanks for the bolts. I'll post a pic for those who asked about these bolts - UNC, 3/8" diameter, 1 1/4" long.

NB further to my first post, Somerford Mini now tell me they do not have the early genuine AP slave cylinders. LMS Ritchfield apparently do, if not I'll try David Manners. Powertrack do not have genuine AP Caparo either.

Cheers
Mike

PS now on to try the Lazza/Brake Fairy brake pedal master cylinder bleeding trick!
M Wood

Pic of remote bleed.


Alan Anstead

This thread was discussed between 10/07/2018 and 17/07/2018

MG Midget and Sprite Technical index

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