Another way to save time on the clutch Hydraulics

[Mrmerlin]

I am working on a 86.5 and part of the job was to replace the clutch master and slave and blue hose.
Given that its usually pretty hard to get out all of the air from the system easily, and not use a whole lot of blue fluid to boot, I removed the whole system from the car, its pretty easy.
Disconnect the battery, cut the blue hose from just under the resivour and catch the fluid that comes out. remove the 2 bolts that hold in the master cylinder.
Remove the pushrod from the clutch pedal and also the rubber boot from the master(This is important as keeping the bellows on will make removal difficult).
From under the car remove the line holding connection at the swaybar mount , the heat shield at the left exhaust header and remove the 2 bolts on the oilpan that secure the line.
Remove the slave to bellhousing bolts, remove the starter. the pushrod for the slave should be able to be pulled out of the slave, the whole clutch hydraulic system can now be removed from the car, it may take a bit of manuvering and the top hard line may need a slight bit of bending, not much to get it out.
Then on the work bench refit the new master and slave to the old lines paying attention to the orientation of the hoses to the respective cylinders.
After this open the bleeder on the slave and put the master in a vice, hold the slave so its higher than the master and using an oil pump type can filled with fresh brake fluid begin filling the master thru the new blue hose till the fluid comes out of the bleeder try to move the lines around so to make sure that any air pockets are moved to the slave, all of the air should purge from the system.
Secure the bleeder, plug the blue line with a clean bolt. Remove the rubber bellows from the new master cylinder and add some tape to the exposed end so dirt dosent get into the end when refitting,
Refit the whole system into the car starting with the Master, once the bolts are installed, the blue line should be connected and the resivour refilled, then secure the swaybar mount followed by the starter then the slave to bellhousing. refit the master pushrod and bellows, adjust so it is not pressing on the master leave about 1 to 2 mm of play .
Bleed the clutch with your favorite power bleeder or helper, you should find that the clutch will be hi and hard with little or no air , so you will use about 1 oz to bleed it. dont hold the bleeder open for more than about 3 seconds as the resivour may drain since its a smaller resivour. reconnect the battery, Done, and no wasted fluid and no skinned knuckes from trying to remove the fittings on the cylinders.
As a side note now is a great time to clean out the resivour.
To do this i pulled out the resivoiur, drained out the old fluid and sprayed brake cleaner into the res.
After doing this i took simple green and sprayed this followed by a hot water flush of the resivour then i took isopropl alcohol and sloshed it a few times followed by a blow dry with compressed air, now the resivour looks like new and all of the old dirt is removed from inside

[AO]

All in a single paragraph!






j/k

[leperboy]

Originally Posted by Andrew Olson

All in a single paragraph!

It's because Stan wants to put all his focus and energy into that very, very special 86.5 he has in his garage. Please don't distract him.

Good writeup, Stan.

Matt

[largecar379]

I agree---absolutely the best way to do hydraulics repair, take it all out and replace everything.


--Russ

[Ispeed]

I was able to replace the guts of my master cylinder instead of doing the whole mc. It is really just the rubber seals that fail, probably $2 worth of parts. Still about $70 for a new mc is cheap compared to having NO clutch and needing a flat bed to Bubba's Garage.
Always keep fresh fluid in the brake/clutch system!!!!!!!!

[Rob Edwards]

In the past week I've submitted an NIH grant, revised a manuscript, and graded a bunch of midterms from my graduate students' immunology course. Here's my edit of what Stan said: (I only did this 'cause I will need these instructions soon and I really appreicate you writing it out, Stan! )

I am working on a 86.5 and part of the job was to replace the clutch master and slave and blue hose.
Given that its usually pretty hard to get out all of the air from the system easily, and not use a whole lot of blue fluid to boot, I removed the whole system from the car:

1. Disconnect the battery, cut the blue hose from just under the reservoir and catch the fluid that comes out.

2. Remove the 2 bolts that hold in the master cylinder.

3. Remove the pushrod from the clutch pedal and also the rubber boot from the master(This is important as keeping the bellows on will make removal difficult).

4. From under the car remove the line holding connection at the swaybar mount , the heat shield at the left exhaust header and remove the 2 bolts on the oilpan that secure the line.

5. Remove the slave-to-bellhousing bolts, remove the starter. The pushrod for the slave should be able to be pulled out of the slave

6. The whole clutch hydraulic system can now be removed from the car.It may take a bit of maneuvering and the top hard line may need a slight bit of bending, not much to get it out.

7. On the work bench refit the new master and slave to the old lines. Pay attention to the orientation of the hoses to the respective cylinders.

8. After this, open the bleeder on the slave and put the master in a vice. Hold the slave so it’s higher than the master. Using an oil pump type can filled with fresh brake fluid, begin filling the master thru the new blue hose till the fluid comes out of the bleeder.

9. Try to move the lines around so as to make sure that any air pockets are moved to the slave. All of the air should purge from the system.

10. Secure the bleeder, and plug the blue line with a clean bolt. Remove the rubber bellows from the new master cylinder and add some tape to the exposed end so dirt doesn’t get into the end when refitting,


11. Refit the whole system into the car starting with the Master. Once the bolts are installed, the blue line should be connected and the reservoir refilled.

12. Secure the swaybar mount, followed by the starter, then the slave to bellhousing.

13. Refit the master pushrod and bellows, adjust so it is not pressing on the master leave about 1 to 2 mm of play .


14. Bleed the clutch with your favorite power bleeder or helper, you should find that the clutch will be high and hard with little or no air , so you will use about 1 oz to bleed it. Don’t hold the bleeder open for more than about 3 seconds as the reservoir may drain, since it’s a smaller reservoir.

15. Reconnect the battery, Done, and no wasted fluid and no skinned knuckles from trying to remove the fittings on the cylinders.


16. As a side note now is a great time to clean out the reservoir. To do this I pulled out the reservoir, drained out the old fluid and sprayed brake cleaner into the res. After doing this I took Simple Green and sprayed this followed by a hot water flush of the reservoir. Then I took isopropyl alcohol and sloshed it a few times, followed by a blow dry with compressed air. Now the reservoir looks like new and all of the old dirt is removed from inside.


If this were for credit, I'd give Stan an A+.

[sharkmeister85]

Originally Posted by Rob Edwards

....Here's my edit of what Stan said: ........

Nice edit! Any chance you have a few pics to slide in there?
Glenn

[Rob Edwards]

Ooh, a challenge!

Well, I haven't actually done the job yet (I'm going to tear the bottom off the car over Christmas week- clutch (and hydraulics), TT, shocks/springs all around, tranny mounts, CV boots, wheel bearings), but here's some 'teaser' pictures of my upcoming clutch hydraulics R&R:


Clutch slave cylinder:



Clutch hardline loop around heatshield at firewall:



Clutch hardline pasenger side:



Clutch hardline to slave bracket:



Clutch hardline at swaybar mount:







And the clutch pedal, just for the hell of it, 'cause I happen to have a picture of it (dunno why....) :

[sharkmeister85]

Rob,
I'll grade you A+ for effort! However, I'll have to dock you a few marks because the original topic refers to "86.5". I don't think the hard line and mounting points on my '85 are quite the same as the ones pictured.
Glenn

[SharkSkin]

Nice writeup...

[docmirror]

I thought about this while I'm refreshing my clutch plate and ball release bushing. Maybe while I have the starter out is the right time to do it.


Another thanks, I figure this would be just as easy, cause I wanna bleed the brakes this week too.

[Mrmerlin]

Hey Rob Thanks for the nice edit job, Id give you a gold star or A++ . Stan

[Fabio421]

MMerlin, I think this method has merrit. I would add one aditional step at t he beginning. Loosen the four nuts that hold the brake booster to the firewall and pry it away from the firewall with a scredriver or something similar. This will give extra clearance when removing and installing the clutch master. Every millimeter counts in this case.

Otherwise, great writeup

[dr bob]

I'm still of the inexperienced and therefor unqualified qualified opinion that one should be able to unbolt the slave, tilt it so the pushrod end is down slightly, pressure bleeder attaches to slave bleeder, push old fluid and bubbles up into the MC and the reservoir.

I need to buy an '89 S4 5sp, low miles, black with cashmere, champaign, linen, classic grey, or light grey, otherwise condition and mileage similar to what I have now. Just so I can experience a clutch fitment, a shift linkage rebuild, and the hydraulic joys that come with the manual trans cars. Not sure I'd drive it much in stop-and-slow LA traffic, but I do have a nice road in my backyard that begs a manual shift car.

[Rob Edwards]

Bob-

At some point in the near future I will be playing with a new spec clutch , and WIAIT, I have a new clutch master, clutch slave, and blue hose o' death that I'm going to install at some point. (My master is weeping into the footwell slightly) You are free to come watch, it'd be cheaper than buying a car to practice on.....