Where to install my Hydraulic master cylinder clutch?

[mopar440cu]

Does anyone know where I can find instructions on where to place my hydraulic clutch MC on my 1979 CJ5 firewall? The firewall is not indented nor marked and I can not find out any info on searches. If anybody has done this on a firewall without the factory markings please let me know how you did it, or if anyone can measure theirs compared to the original brake master cylinder.

My other question is also pertaining to the master cylinder. I purchased a Novak 3/4" slave cylinder HCRA-34 with the fittings and hoses HCR8-34, but I am trying to figure out which master cylinder to use. Novak suggested using a CJ 1980-86 clutch master cylinder. For these years am I looking for MC for a 4 cylinder, as I read on others write ups?Also, anybody use different MC?

One more quick question. Lol There seems to be conflicting comments on whether to use a YJ clutch pedal instead of drilling out my original clutch pedal. Any thoughts? What year YJ, if I go this route, am I looking for?

I posted this on some other Jeep forums and got a couple of responses, but the more the merrier. You can never get enough knowledge! Lol

Thanks for your time!

 

[mriplaybass]

I don't have exact measurements to give you, but you can pretty well see where I mounted mine and go from there.

This is on the firewall between the power brake booster bracket and the fuse block.


This is a view of the MC mounted.


View from the inside with the clutch pedal removed.


Position of the 1/2 x 3/8 shoulder bolt.


I drilled and tapped the clutch pedal arm, then used a nut to jam the shoulder bolt to the pedal arm to prevent it from backing off.



I plan on doing a full write up on the conversion soon, but this should give you a good idea on where to mount things.

 

[mopar440cu]

OK back to other questions. LOL I now have a 87 Jeep Wrangler clutch pedal assembly to help with the install, but don't know yet whether I am going to use just the clutch pedal off it and combine it with the jeep stuff or use the whole combo. Anyhow my question is should I be using a Wrangler hydraulic clutch master cylinder? I cant seem to find specs on the throw of it because Novak said it should be the same throw as the one I bought a 3/4". Anybody know what the throw is? When I had them on the phone they also suggested just using the MC off a 80-86 CJ w/2.5L, but they said the pedal would be a little stiffer than normal. I really want a less stiff clutch pedal for the wife, I am sure yall understand. I like the Wilwood MC, but don't know how to install the necessary rod and ends to get it to adapt to our Jeep CJ5 . Wilwood said the one I am looking at is basically for a Ford and I would have to modify it. Anybody done the Wilwood adaption? If so, have any info and pics please?

Again thanks for all the Help!!!

 

[caveman]

There's something different with YJ and CJ pedals. I don't remember what it was. It was a long time ago. I put an auto Transmission in a YJ and had an auto brake pedal out of a CJ and thought they were interchangeable, But not so. Compare them closely before you commit to something that can't be reversed. A lot of ford stuff will fit Jeeps. Jeep used their stuff because it was cheaper than designing there own.

 

[mriplaybass]

I used the master and slave cylinders from an early 80s CJ. Both the 6 and 4 cylinder uses the same parts. If I recall correctly, the throw on the clutch fork of my T-18 is 1 1/4". The part numbers I used are CENTRIC 13663006 for the master and 13863001 for the slave (Rock Auto). The master is a 3/4" bore, and the slave is a 13/16" bore. They are intended to be used together. It was extremely easy to use the stock CJ pedal. Just had to drill a hole for 3/8" threads. Unfortunately, even though the slave cylinder was a direct bolt up to where the bell crank pivot was, it was too high and I had to make an adapter bracket for it. No drilling of the bell housing was necessary.
You also want to get a clutch throwout lever pivot. It is a little cap that goes between the clutch push rod and the throwout lever arm. It takes up the extra distance caused by the adapter plate and allows you to use the rod that comes with the slave cylinder, Crown P/N J3217479.
Once I had everything together, with the clutch pedal all the way to the floor, the slave piston was still at least 1/4" from the end of the bore. If your Transmission or clutch fork is different, and the included push rod does not work, you can easily use the adjustable rod from the bell crank by grinding the end that goes into the slave cylinder round. That way you can adjust it just like when the bell crank was still in.
The amount of pressure on the pedal is about the same, but even sites like Novak say that hydraulic conversions will not make much difference in the amount of effort required to operate the clutch.

 

[JR74CJ5]

Bass - side note - you may put a bit of heat shielding around that line at least, or the exhaust itself depending on type you get. You might also use the hydraulic fluid that is harder to boil (forget DOT rating). Mine isn't close enough, but I have the fender well headers, not inside frame rails exhaust like you... I've heard people have issues with it if long drive / lots of trail idling...

Looks great man! I'm hoping you like the mod! No more clutch linkage binding on the trails! lol

Miss you guys!

 

[mriplaybass]

That's on the tado list . I just wanted to get things mocked up, then working before I create even more obstructions for myself with the heat shield. I also have that side of the exhaust wrapped with header wrap normally. That reduces a great amount of heat. I can actually touch the pipe with the engine running without burning my hand. I took the wrap off to drill the hole for the Sniper O2 sensor. It will be going back on along with a heat shield and fuel line heat wrap on the clutch hydraulic line.

 

[Lumpy Grits]

Nicely done Bass!

X2 on a heat sheild.
What fluid is this spec'd for?
DOT5 is syn fluid.
Our jeeps are DOT3.
LG

 

[JR74CJ5]

That's on the tado list . I just wanted to get things mocked up, then working before I create even more obstructions for myself with the heat shield. I also have that side of the exhaust wrapped with header wrap normally. That reduces a great amount of heat. I can actually touch the pipe with the engine running without burning my hand. I took the wrap off to drill the hole for the Sniper O2 sensor. It will be going back on along with a heat shield and fuel line heat wrap on the clutch hydraulic line.

That's right - you did have it wrapped in CO - I remember now... Sweet deal - looks good, and your brackets look good too man.

You're doing the sniper FI mod? :drool:

What fluid is this spec'd for?
DOT5 is syn fluid.
Our jeeps are DOT3.
LG

I normally use DOT 3 in mine I believe, I think DOT 4 has a higher heat rating for boiling point though, and think that the master and slave cylinders would work with either, Never messed with DOT 5. Actually haven't messed with any of them except the DOT 3 normal stuff. I just read somewhere about the different heat ratings and whatnot and am going off memory...