Clutch Master Cylinder Assistance

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timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Clutch Master Cylinder Assistance

Post by timteague »

I have read a couple of posts describing the r an r of the clutch master cylinder and it seems no one considers it a BIG DEAL. I have gone on the floorboard twice to try and get the 2 retaining bolts out and the bracket and clutch lever have made it impossible to get to. Should I just remove the entire clutch pedal and bracket for more room? Also...is the line going out of the top of the cylinder going to be a serious headache as well? Thanks for any instruction!
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Thanks for that! I purchased a small old-school oil squirt can and tubing to push fluid from the bottom up. Will fill the oil can so as to not get air in. Hopefully that will make that part of the project easier. I was tempted to only replace slave since that is probably the problem, but I can't stand to do one part and leave the other which may be 36 years old!
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

I did it last year.
It wasn’t too hard, but as I recall there’s definitely a preferred order of removing/unscrewing/loosening things.
Try a google search, you’ll find info (either on this site, or others).
I believe I posted some tips (but I don’t recall where!).
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Here it is, cut and pasted:

I just did this job on my ‘86 today. I thought I’d add on to the thread for those that Google and find it (like I did).
My suggestion, respectfully, is to try the simplist approach first.

1. Using a flashlight, I was able to see the end of the clutch master poking into the engine bay, right under the brake “bomb.” Yeah, it’s a little tight access, but nothing too crazy. I was able to just get a regular 11mm flare wrench down there and unscrew it. I could have used an open end and it would have been ok too.
2. Inside the cabin nothing too special. The lower mounting bolt is a little hard to get to. Need a small 1/4 inch drive 10mm socket and short extension (4-5 inches is perfect) for that. 3/8 drive is too big.
3. Like others have said, installing the feed line into the clutch master cylinder can be very difficult. Very. There is no room up there to work. The easiest way, by far, to do this is use a new line and plastic fitting on cylinder. That way, you can put the plastic fitting into the master cylinder, and attach and clamp down the line, all while it’s out of the car. It’s a very tight fit. And, you get the benefit of a new line.
4. For me, the order of operation installing the part in the car was very important. First, run the new line through the firewall. Then put the master cylinder through the firewall, but DON’T bolt it up. Then, in the engine compartment screw on the output hard line to the end of the cylinder, do this by hand and hand tighten as much as possible. Then bolt everything up from the inside. Then tighten the output line with the 11mm flare wrench. Attach the new line to the fluid reservoir.
5. If you use a pressure bleeder the clutch line bleeds easily and quickly. I just use 5 psi.

That’s it. IMO no need to remove the seat, get on your back upside down under the dash, etc.
If the output line is on super tight and the 11mm flare wrench seems in danger of stripping, I can see how some other more involved measures may be necessary. But I’d for sure just try the simple method first, just reach down there with you flare wrench and try.

If all goes well, it’s not more than a couple hours.
Last edited by Jubilados on Mon Apr 25, 2022 12:15 am, edited 1 time in total.
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Great info. Thanks! Knowing the bolt sizes is half the battle when you can't see it from above or below.
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Well that was quite the task! I spent an hour just getting the bolts out of the body of the mc. I couldn't find a 11mm flare wrench so will pick back up when I buy one. More to come.
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

You unbolted the MC from the chassis before loosening the 11 mm hydraulic line?
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Yes...and the pivot bolt connecting it to pedal. Is that catastrophic? :(
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Not catastrophic (it’s only time), but the order of operation is very impt for this particular job. And you literally disregarded it from step 1 :D
How are you going to hold the MC in place when you try to loosen the 11mm hydraulic line?
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Looks like I will be be loosely reconnecting the MC. :(
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

This is one of those quirky jobs. It can be pretty straightforward, or one can make it into a very difficult (or near impossible) job. Reading on the Internet, I see people making it much harder than necessary, disassembling unnecessary things, taking the front seat out, lying on their backs, and doing things out of order that makes it 10x harder.
Read and follow my 4 steps closely. Esp. on the reassembly (steps 3 and 4).
For example, if you were to bolt the new MC in place first, then try to install the plastic tube and/or feed line onto the new MC while the MC is bolted in place, you’d be in for a miserable time. There’s just no room to work under there.
Could it be done? Maybe. But it would be very, very difficult, and completely unnecessarily so.
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Yes. Thank you. Order is everything!
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Back to the replacement of the Master Cylinder. So far I have now completed steps one and two, everything disconnected. However there is a missing step. After the two steps I now have one more line on top of the master cylinder that I do not know how to remove. Not sure if it is friction line or a fitting. This is preventing me from removing the device. Do not want to tear anything up, but need a step 2a in the instructions. I purchased additional line for the replacement, but can't tell the type of connector. Thanks!
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

It’s been a while since I did mine, so I’m going by memory, but as I recall there’s only one line going into the Clutch MC. One going in, and one going out (the out one is the 11mm one you removed from inside the engine compartment).
See picture showing the single in line.
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timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Thank you. I am just trying to figure out the best way to remove the line that goes in to the top of the cylinder. I can only feel it, but can't see it so I can't tell how it's connected. I wonder if disconnecting the line inside the engine bay then pulling through the firewall to the cabin. Thoughts?
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Yes, remove that feed line from the engine bay and pull it out through the cabin.
You can now see why the assembly order is important. If you bolt the cylinder in first, then try to get that line on and tightened up, you can see how difficult that would be. No room to work.
So on assembly, insert the plastic piece into the MC, put the line on, tighten the hose clamp up, then thread the line back from inside the cabin into the engine bay.
Last edited by Jubilados on Mon May 02, 2022 2:01 am, edited 2 times in total.
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

This plastic piece goes into the master cylinder feed hole.
Then the feed line is secured onto the plastic piece with a hose clamp.
I’d suggest having a new one of these on hand, just in case you break the original one trying to get it out of old MC. It’s a very tight press fit.
Attachments
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Last edited by Jubilados on Mon May 02, 2022 1:57 am, edited 1 time in total.
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Looks like this
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B2E2A1B6-1485-411D-8DD8-42EF107C4F11.jpeg (374.29 KiB) Viewed 1691 times
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Excellent! I will stop trying to take the hose out of the top and will remove the connector in the engine bay. I did buy the extra connector and tubing so should be good to go. Will keep you posted. I also may add some steps to the instructions for those less experienced like me.

Thanks!
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Now that everything is out with replacements ready, I am wondering if anyone has found a braided line replacement between the slave and the master instead of the existing curved solid one?
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

What’s wrong with the solid one?
That line connects 2 bolted, basically non moving parts.
A hard line is best for that application (which is why the factory did it).
timteague
Posts: 19
Joined: Mon Feb 07, 2022 1:08 am
Location: Tennessee (TN)

Re: Clutch Master Cylinder Assistance

Post by timteague »

Yea. Makes sense. I was trying to find an easier way to correctly position it between the slave and master to better match the ends. Getting the master cylinder end to match the hard line is tough without being able to see it. Should have left it connected and fished out through the firewall to the footwell.
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

Did you follow the order in Step 4?
The reason it is in that order is exactly because of that hard line.
Jubilados
Posts: 161
Joined: Sun Mar 08, 2020 4:48 am
Location: So Cal

Re: Clutch Master Cylinder Assistance

Post by Jubilados »

In other words, if you bolt the MC to the body first, THEN try to get that 11mm threaded in the engine compartment, you will have a very difficult, or impossible, time.

But if you push the MC through into the engine compartment, then BEFORE bolting it in place you thread the 11mm line on by hand, to get it started, then finally bolt the MC down, then tighten the 11mm with a wrench, it’s not bad.

Doing it that way allows the MC to move around to let it line up with the 11mm.
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