Hydraulic Clutch Conversion

[Neuner]

I want to make the change to a hydraulic clutch. Debating whether to do it now or later depending on several factors. Doing research, I'm getting confused.

Never found a direct helpful list of parts and process to clear things up. Looks like those that have posted have grabbed parts from very early CJs to YJs to make it work. I read of making brackets and drilling new holes all over the place to line things up or buying the conversion kit from Novak. I keep wondering why I can't just buy the Master and Slave Cylinder that comes up for my vehicle under an auto parts store search and simply bolt it up? Not sure why there's such a mix match of parts and process for this conversion.

 

[Lumpy Grits]

Happy trails--
LG

 

[Neuner]

Please don't sidetrack my question.

 

[hdgapeach]

Would this get it done?
Hydraulic Clutch Conversion AMC Jeep CJ5 CJ7 CJ8 | eBay
Just did a quick search and it's what popped up. I'll be the first to admit, I have zero experience with hydro conversions. Looking at this "kit" makes it seem like a pretty straightforward conversion.

Modification are always owner specific. I guess this one is not different. You could beat the bushes for individual parts to create most anything you desire. I'm more apt to jump on an already assembled "kit" now days that'll ship straight to my door. I gotta factor in fuel costs along with the parts costs when I do a project. Living in the sticks does have a drawback or two sometimes

 

[Purple77CJ7]

I did a hydraulic clutch conversion in my Jeep some years back. I used Advance Adapters, they have a list of the parts you need. You use late 80's parts. I had to drill the mounting hole in the firewall. You could sort of see in the firewall were it needed to go and drill the clutch pedal arm for the linkage to attach. Lots of measuring. Mid 80's they switched to hydraulic clutch. Early 80's and my 77 only came with the mechanical linkage. One of the best conversions that I have done. It's really not that difficult to do.

 

[Lumpy Grits]

I did a hydraulic clutch conversion in my Jeep some years back. I used Advance Adapters, they have a list of the parts you need. You use late 80's parts. I had to drill the mounting hole in the firewall. You could sort of see in the firewall were it needed to go and drill the clutch pedal arm for the linkage to attach. Lots of measuring. Mid 80's they switched to hydraulic clutch. Early 80's and my 77 only came with the mechanical linkage. One of the best conversions that I have done. It's really not that difficult to do.

The 6cly CJ, used mechanical linkage till the end of production in 1986.
Only the 4cly used hydro--
LG

 

[ThisGuyUKnow]

I want to make the change to a hydraulic clutch. Debating whether to do it now or later depending on several factors. Doing research, I'm getting confused.

Never found a direct helpful list of parts and process to clear things up. Looks like those that have posted have grabbed parts from very early CJs to YJs to make it work. I read of making brackets and drilling new holes all over the place to line things up or buying the conversion kit from Novak. I keep wondering why I can't just buy the Master and Slave Cylinder that comes up for my vehicle under an auto parts store search and simply bolt it up? Not sure why there's such a mix match of parts and process for this conversion.

Master cylinder from a 87-90 Yj. Go ahead and get your self a pedal assembly from an 87-90 yj as well, then all you have to do is pretty much bolt it together no measuring required to get the geometry correct.

If you are keeping the CJ tranny, the slave may be a little tricky to fab up yourself but if you can find something that works, any hydraulic shop can make you a custom hydraulic linkage to mate the MC to your slave.

Honestly if you are keeping a CJ tranny I think your best bet and serviceability is going to come from a premade kit that has a slave designed to function the manual throw out fork. if you are using a tranny that originally used a hydraulic clutch then all you need is a custom hose to mate it to the MC.

 

[73CJ]

Lots of web article on the conversion.

Stock pedal can be drilled and a clevis pin welded in.

I used 1990 parts

A worth while modification

 

[tarry99]

I want to make the change to a hydraulic clutch. Debating whether to do it now or later depending on several factors. Doing research, I'm getting confused.

Never found a direct helpful list of parts and process to clear things up. Looks like those that have posted have grabbed parts from very early CJs to YJs to make it work. I read of making brackets and drilling new holes all over the place to line things up or buying the conversion kit from Novak. I keep wondering why I can't just buy the Master and Slave Cylinder that comes up for my vehicle under an auto parts store search and simply bolt it up? Not sure why there's such a mix match of parts and process for this conversion.

There is no one size fits all..........Your 1985 with the AMC 258 i6 / 4.2l was never offered with a hydro clutch........the 80-83 CJ was with the GM Iron Duke 4 cylinder. Perhaps your body / firewall may still have a printed knock out looking area to the right of your master cylinder if looking from under the hood...........not hard to install but the proper firewall location must be had along with the proper push rod ratio to the clutch pedal arm.......If yours is not marked on the firewall find a 1980-83 CJ and take a look.
The reason for the proper location and pedal ratio is simple.......one is that you are pushing fluid and the proper amount of stroke is critical to get enough movement at the slave cylinder to release the clutch.......the second is that if the ratio is incorrect the pedal will be hard to push down.........
So the height of the clutch master center line has to be correct as compared to the fulcrum point of the pedal assembly.........the ratio you need is about 6:1........once you have the correct center height and that location is also in line with a point on the clutch pedal arm drill away..........

You also have to fabricate a bracket that will hold your slave cylinder at either your bell housing or Transmission to actuate the clutch fork. Slave cylinders can be had that will either push or pull , meaning you can mount the cylinder on either side of the clutch fork.

Here is where things get tricky (and here is where most folks make a mistake and then later complain that there clutch system does work very well) and here is also why you need to do your home work on pedal travel and correct clutch master cylinder bore size and volume.....at the clutch fork and slave cylinder all actions coming off of the slave are a 1:1 ratio but as soon as it hits the fulcrum ball on the clutch fork it changes to a 2:1 or 50% of travel.........a standard clutch pressure plate at the throughout bearing takes about .400-.625" of movement to fully release the clutch disc. Add another .125-.250 of free play to the system...........that means at the clutch fork that dimension is double that or up to 1.750" of travel. That is why lots of folks like the Novak slave cause it has up to 2" of travel where most OEM cylinders only have about 1.250-1.500" of travel...........Not to say you will need that much travel but some clutch packages do.

Confusing Yes.......But not that hard to do if you pay attention to all the principals.

 

[gyvrr]

My 85 started with a hydro clutch....4WP had the slave cylinder and line assy.
I just put them together and they have been working fine for the last 5 years.
My thoughts Get a clutch petal for a 4 cyl from your local junk yard with the push rod and order the rest from 4WP. Be sure to add a spring from the clutch fork to the slave cylinder to prevent any accidental bump and loss of the push rod.

 

[Neuner]

Thanks for the information, I appreciate it. A good explanation as to why I couldn't find anything concise in my far reaching search.

Thanks Tarry. With your information I think I'm convinced to get the Novak adapter/bracket and slave cylinder. I also like how it is adjustable.

 

[73CJ]

My slave bolted right up to the bell housing

I used this article but looks like it disappeared off the net