Repair of clutch master cylinder (with photos)

[ourmark]

I am too tight to pay for a new master cylinder, so today I had a go at fitting new seals instead.

I bought AP Lockheed repair kit LK 11231 off ebay for about £8 including delivery.

First, I removed the clevis pin from the top of the clutch pedal. There are no photos of this stage because it's done mostly by feel.

Next, remove the plastic cover from under the bonnet. I had to give the plastic nuts a little help to come off:



With that out of the way, it is easy to see the clutch master cylinder:



Remove the pipe from the top, taking care to catch any drips:



Remove the 2 bolts and lift the cylinder out of the bulkhead:



Peel back the rubber boot and remove the circlip. The cylinder spills its guts:



The cylinder in bits:



Old seals removed:



New seals fitted using some brake fluid to lubricate:



Putting things back together with some red rubber grease. The cylinder body was cleaned using alcohol wipes and the reservoir had some brake fluid poured in and then I gave it a good shake before emptying it out:



The circlip is back in. Just need to push the rubber boot back on and fit it to the car:



Put it back in, fill the reservoir and then bleed using the bleed point on the slave cylinder. Total time about 4 hours.

Problems:

My circlip pliers were too large to fit the holes in the circlip. I made do with a pair of needle-nose pliers.

The cylinder insides were different to the diagram in my repair kit. Instead of easily coming apart, it was all one unit so I had to stretch the seals over the length of the shaft to get them on. Much swearing was required, but they went on.

I've disturbed the brake light switch while messing around in the footwell. I'll have to reset that tomorrow.

Link to album of all images

[ourmark]

Hmmm... not all of the photos are showing. Gonna try uploading them somewhere else.

[Reaper]

Very usefull!!

[MGFmad]

Good work there, an excellent how to

[gotenks1321]

You make it sound so easy to remove it from the car That rear bolt is a right pain in the arse!!!

Good job I've got the one I took of my car a few weeks back to replace the seals in, must get round to it one day

[Petevick]

excellent how to. Just one small point, you make reference to the 'slam panel' as being the plastic moulding at the back, its not, the slam panel is what the bonnet catch locks in at the front, the moulding has the grand name of an 'under bonnet cover'.

[ourmark]

Thanks guys, and thanks for the correction, Pete. I've edited my post.

[Tim.]

Nice post. Have some rep.

I've got a screwdriver like that. One of my most used tools.

[ourmark]

Thanks for the rep!

If anyone has trouble with images not loading, all these (and a few more) are also here

[MGFNorway]

Excellent job!

[pascandrea]

Hi
thanks for the nice tuto, but could you tell me why you have change it, what was the symptom on the clutch ?
thanks

[ourmark]

Originally Posted by pascandrea

Hi
thanks for the nice tuto, but could you tell me why you have change it, what was the symptom on the clutch ?
thanks

I'd had problems with the clutch sticking for the last 9 months. I bled the system and greased the arm and that worked for 6 months before the clutch stuck again. About 2 months ago, I replaced the slave cylinder which got things working again, but I was unsure of the state of the master cylinder for a couple of reasons:

First, the pedal felt slightly uneven, as if it was bouncing back at the top of the pedal travel.

Second, the fluid was discoloured even though it had been replaced twice in recent months.

So although the car was driveable, I thought it best to sort the master cylinder. Then I've done the whole lot and I can hopefully get another 50,000 miles out of it.

One more thing to mention is that I'd replaced the clevis pins on both cylinders with stainless steel ones. Yesterday I was able to check them after 2,000 miles and they have no signs of wear.

M8x16mm fits the slave cylinder and M8x20mm fits the master cylinder. If you want to use a washer, then you'll need to go one size bigger on each of these. I chose not to because where they are located, I'm more likely to drop a washer and lose it than I am to get it on to the pin. There isn't much rotation on these joints and therefore the R-clips don't suffer from not having a washer, IMO.

[ourmark]

Just a little update now I've driven the car some more.

The clutch pedal feels very smooth. For some reason, I thought it might feel lighter but if anything it's got slightly heavier. But the odd "bouncy" feeling has gone so that's good.

I haven't heard any squeaks from the pedal since doing this, either. Maybe it is too early to tell, as the squeak used to come and go, but if it's gone then that's really, really good.

Very happy with the results from doing this work and I can't wait to do the brakes next. I'm planning a master cylinder rebuild along with braided hoses and new pads.

[_MEME_]

i have same problem with the clutch...srry but i cant see your photos

[ourmark]

Images should display correctly now. Good luck with it!

[Broon]

Great post!! Thanks