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[Andy A]

My clutch felt fine and gear changes were smooth for well over a year. The fluid level was low all that time but above the minimum line. I didn't realise that it was below the min clutch fluid pipe.

I started to have difficulty getting into 1st and reverse when the engine was running but went into gear fine with engine off.

I reverse bled the clutch 4 times. The clutch feels like it did before not spongy but firm. Gear changes have got worse after the bleed.

I think I may still have air in the system. Is there any way to pressure bleed the clutch from the top?

I think I read somewhere that if I press and keep the clutch pedal to the floor when pressure bleeding from the top it would eliminate any air. Has anyone else tried this method and did it work?

Thanks

[Matchless]

When you press the clutch pedal down, the first part of the master cylinder travel closes the port leading to the reservoir so you can only pressure-bleed with the pedal fully up.

Bleeding from the top down is often unsuccessful because of the vertical section of pipe from master cylinder to slave. I suggest you try pressure-bleeding from the clutch bleed nipple back up to the reservoir. If you remove the bleed nipple first and wrap a turn of ptfe tape around the threads you wont get quite so wet.

The symptoms you describe are those of clutch drag. If you are sure that the clutch is bled properly then you have to consider clutch contamination. Is there any sign of oil (engine or gearbox) visible on the flywheel? There is a window somewhere that lets you see the front of the flywheel. Has there been a coolant leak recently at the back of the engine?

If no improvement then you will have to remove the box to investigate further.

[Andy A]

When you press the clutch pedal down, the first part of the master cylinder travel closes the port leading to the reservoir so you can only pressure-bleed with the pedal fully up.

Bleeding from the top down is often unsuccessful because of the vertical section of pipe from master cylinder to slave. I suggest you try pressure-bleeding from the clutch bleed nipple back up to the reservoir. If you remove the bleed nipple first and wrap a turn of ptfe tape around the threads you wont get quite so wet.

The symptoms you describe are those of clutch drag. If you are sure that the clutch is bled properly then you have to consider clutch contamination. Is there any sign of oil (engine or gearbox) visible on the flywheel? There is a window somewhere that lets you see the front of the flywheel. Has there been a coolant leak recently at the back of the engine?

If no improvement then you will have to remove the box to investigate further.

1. Never bled a clutch before. So not 100% sure its correct. But it feels nice and firm/springy.

2. None at all.

3. No coolant leaks.

So reverse bleed is the only way. 

I guess it must be down to not bleeding properly. it did get slightly worse after bleeding.
I will put some ptfe tape around the thread of the nipple. Maybe some air was getting past the thread.

I did just read that a smear of grease around the nipple might work as well.

I used a new small oil can to reverse bleed last time. I will make an adapter up for the pressure bleeder to pressure reverse bleed. 

Thanks for your advice and help. 

[Matchless]

Dont use ordinary grease on any brake or clutch system, it can cause rubber seals to deteriorate, there used to be a special grease that could be used on pistons and seals but I havnt seen it sold for 20 years or so.

I use a simple piece of plastic tubing to link an easy-bleed to the clutch bleed nipple---just dont apply much air pressure to the easy bleed else the pipe pops off and you get very wet, very quickly.

[Andy A]

Found some silicon type grease that is safe for piston seals. 

It was down to air getting past the nipple thread and I have now successfully bled the clutch and all is back to normal. The strange thing  is that the clutch feels just as firm and springy as it was the other day. Must have been just enough air in the sytem to cause clutch drag and the pedal to still feel firm.

Thanks Matchless for all your advice and help. 

[terry paget]

I use Eezibleed for bleeding brakes, works well. I did not find it work so well on the clutch, however. I reverse bleed the clutch by gravity, as follows: I attach a  6' long plastic hose to the clutch bleed nipple, unscrewed, with a funnel on the end; I hang the funnel from a rafter in my garage; I pour brake fluid into the funnel; tube fills with brake fluid; I top up the funnel occasionally, and watch the fluid level rise in the master cylinder reservoir; most satisfying.

[Andy A]

That's a good idea for a one man bleed Terry.