MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Clutch Hydaulics help

RE 1600 Mk 2.
I know this has been the subject of a number of threads but I am stumped.
I have recently replaced clutch, thrust bearing, master cylinder and clutch slave including new hose - all from Moss Europe.
Have bled the whole system, the clutch 3 times including back bleeding.
Despite all of this the clutch pedal still needs to travel almost to the floor to disengage the clutch. At times it feels as if the clutch is hardly disengaging at all, particularly into 1st and 2nd.
Brakes are fine.
Your thoughts/advice would be appreciated.


John Follett

How much travel are you getting at the slave cylinder when depressing the pedal?
Dave O'Neill 2

John, Get someone to press the pedal while you observe the effect. If it is a hydraulic problem, with little travel (most likely) it is probably a bleeding problem. Some new slaves have the bleed nipple in the wrong place, i.e., at the bottom. I have solved this issue by unbolting the slave, using a cable tie or G clamp to hold the piston in, hanging the slave with nipple uppermost then bleeding.
Allan Reeling

Yes, I too removed the slave cylinder to bleed the system. I also put the bleed valve at the uppermost point.

Regards
Colin
Colin Manley

Travel at the slave pushrod needs to be a full half inch (12-mm minimum).

Slave end port (lower) is the input port, while the side port (higher) is the bleed port. With bleed nipple in the end port it will never get the air out. Bleed nipple in the end is a shipping convenience only. Bleed nipple must be moved to the side port.

If it bleeder is in the correct port, and it is still hard to bleed, see here:
www.MGAguru.com/mgtech/hydraulics/ht106.htm

barneymg

Thank you one and all. I will inspect tomorrow, and hope for the best! John
John Follett

Thanks for bringing this one up John. I recently fitted a new master cylinder and bled with the Easi-bleed. The brakes are fine but the clutch is almost to the floor just like yours. That's after the 'helper' has pumped and I even reverse bled it with a handy 10cc syringe.
I like the quick pump with the finger over the nipple bleeding idea and have just ordered a visibleed referred to on Barney's site.
We'll get there, let us know what worked John.
Pete
PeteT

This Moss video may help.

https://m.youtube.com/watch?v=uj1dMdYgRK4

Jim
JL Cheatham

Thanks Jim, I had seen that clip but would like to save that idea as a last resort.
Pete
PeteT

Pete, why would you want to keep this bleeding method as a last resort, where it would be my first method to use, pushing the slave cly piston right back and keeping it there while you bleed it, is normal practice,and always works if your problem is air in the system, you don't need to remove anything or disconnect anything, just a large pair of grips to push back the push rod into the cly.
Andy Tilney

Brilliant Andy, I hadn't heard of that particular way of pushing back the piston before. I just assumed the cylinder would have to be removed and a-dangling first, not that difficult but was just trying to avoid it. This is what this forum is all about - thank you friend. When this snow clears up there will be some renewed bleeding effort going on.
Pete
PeteT

Not sure whether my recent experience may help, but here goes.
Clutch has always required pressing to the floor to release. Master cyinder about 1,000 miles old, and slave cylinder more recent. Have bled on numerous occasions, and occasionally get small amount of air. Always bled with ezibleed connected to garage compressor, at 20psi. Recent club run, very embarrassingly started intermittently refusing to release. Managed to drive home, bled again, and again a small amount of air. Clutch working normally, ie released but only with pedal at the floor.
Mike Elsmore gave me some basic measurements to check (thanks Mike), starting at the slave cyl push rod. Should have 3/8" travel. I only had 1/4. Master cylinder travel checked; should have 1/2"travel at push rod with pedal to floor, only had 3/8".
OK. Getting close, obviously pedal not travelling fully. Lifting carpet, found that the trimmer had provided underfelt around 3/4"thick. So gained additional 3/4"pedal travel by removing underfelt. Still not quite the 1/2" I was looking for at the push rods. Then found that the toe panel floor board had been cut a little bit oversize at the top, and the bolts holding the steering column flange were excessively long, and holding the floor board back from correct position. Cut the top off the floor board enabling it to sit correctly, and voila, full 1/2"travel available at the Master cylinder and 3/8"at the slave cylinder.
So, long winded way of saying check the mechanical components as well as the hydraulics. It may be simpler than you think.
On the downside, being a short a**se, I now have to stretch out further to take advantage of the full pedal travel. Moving the seat forward, and I'm up against the steering wheel. I'll have to figure out how to sort this at a later date.
Terry Sheppard, Melbourne
Mike Ellsmore

Somehow Terry has replied to this post that I sent to him for info and it has come up as my post , interesting!
Mike
Mike Ellsmore

Not sure how you're measuring, but there should be at least 1-inch travel at the master cylinder pushrod (maybe a tad more), and about 1/2-inch travel at the slave cylinder (with no air in the system).
barneymg

Terry who ?
Art Pearse

Pete,
You can push the rod into the slave cylinder by hand like in the video if you just remove the pin. Once it's bled, just connect the rod back to the clutch fork and secure it with the cotter pin. I had to use this method on my MGB but was able to successfully bleed the slave cylinder on my MGA without doing this.

Good luck.

Jim
JL Cheatham

Right I've cracked it chaps! As Moss and others have suggested here, I pushed the slave cylinder in as the cylinder is bled, the last of the air popped out and I have my old familiar clutch back.
Now then, Jim, I didn't have to remove the cotter pin. As Andy suggested, I just pushed the whole arm and push rod in but not with 'the large pair of grips'. There just didn't seem to be enough room.
Write this down somewhere...
Get a piece of 2" x 1" timber and jam it between the front of the floor and the clutch arm. Apply leverage, loosen and re-tighten the bleeder - job done!
This achieved the success and the simplicity I was after; I do hate fiddling with those split pins.
Thanks everybody - I'm away!
Pete
PeteT

Pete don't sound so surprised, people have been doing it this way for years,
Andy Tilney

Andy, thank you for planting the idea and I was trying to do as you suggested on the 19th. I had not realised the clutch arm would actually allow this movement but that little bit of wood was so simple and easy and I don't have any 'grips' for that job. I thought folk might like to know what did it for me... Happy Easter!
Pete
PeteT

This thread was discussed between 09/03/2018 and 31/03/2018

MG MGA index

This thread is from the archives. Join the live MG MGA BBS now