No gears, help required

I cannot select any gears when the engine is running, not a sausage. fluid level is ok, it's had a new slave cylinder before I bought it 5 months ago, unfortunately it broke down at work so had to take it to a garage, they say they've bled the slave cylinder and no air, and want to pull engine and gear box for further investigation (costly) as they have no idea why it's doing this, i still suspect air in the system, i would like to disconnect slave cylinder from linkage and see if it moves freely this should prove hydraulics works ok. I think. has anyone got any other ideas

1. You don't need to drop the engine and gearbox to change the clutch so why drop them to investigate.

2. You need to establish whether the slave cylinder is moving the clutch arm by having someone working the clutch while you observe the slave and arm. Is the arm being moved and how far?

3. Is the main hydraulic cylinder working properly. Have the seals gone?

4. Then you know if the problem is hydraulic or mechanical. Has the clutch arm partially siezed?

Got the car back from the garage. They apparently bled the brakes and found no air, want to pull engine and gear box. As cant find a fault. When i got in the car the pedal now just hits the floor with no effort at all. How can a garage have no clue or is it because it's an MG they don't want the hassle. Looks like I have to fix it then

These were my exact plans. Luckily I have spares, but I suspect a hydraulic failure as they can get gears if engine not running. I have a feeling it's not mechanical

Having got it all apart i only seem to get about 5mm of travel on the slave cylinder from full pedal movement. How much should the slave piston move.

I would expect more. disconnect the pin and see how far the clutch arm moves manually (this takes a bit of effort).

If no obvious leaks at slave and its been bled correctly, then its either master cylinder, or sticking arm on the clutch its self. My money is on the latter.

i dont understand how the pedal goes straight to the floor with hardly any effort if its gear box related. There is litterally no reaistamce what so ever

You should definatly have more than 5mm movement.

Having very little feel to the pedal indicates it is not depressing the clutch plates.

This could be a sticking release arm, so try disconnecting the slave cylinder clevis and seeing how easy the arm is to move. It should be free to move, untill it makes contact with the release bearing. If it is tight, or near impossible to move by hand, then the release arm has seized (quite common)

Then the next thing I would do is bleed the clutch.

An "eazy-bleed" kit works wonders on the clutch!

Then see how much clutch arm movement you have. If still very small with no effort, then i would suspect the master cylinder.

If I were looking at this on my car I would just go straight for master cylinder and slave cylinder re-seal , followed by eazy-bleed to replace fluid and thoroughly bleed clutch (remember the pipes are long and go all over the place from front to back, so not as easy to bleed as normal clutch.

Although not a big issue. as the cylinder is angled slightly up, so I suspect some air remains in slave cylinder after normal bleeding, so I also bleed the slave cylinder a little special!

Note this is generally not necessary, but can improve a good clutch to a great clutch!

1 after normal bleeding is complete
2 Press clutch peddle down and hold down with a bit of wood or brick (or a spare wife)
3 Gently release the bleed nipple and allow clutch arm to move back under clutch force
4 by hand push arm further back, forcing the slave cylinder all the way in untill it can go in no further.
5 Close bleed nipple
6 remove wood, brick or wife from clutch peddle and allow peddle back up.

What this does is completely remove any air that might be trapped in the slave cylinder.

Once the hydraulics are 100% then look for other issues in the clutch.