84 CJ7 Hydraulic Clutch Help Needed

Been a while since I checked in guys. Took about 20 attempts to log in because I couldn't remember my password. Logging in from a cell phone because a couple years ago my company decided to block us from goofing off at work.

Anyway, I need some help. I have an 84cj7 that originally came with a 4 cylinder with a hydraulic clutch. The PO put a straight six in it with an NV 4500 transmission. We're using the hydraulic clutch system that was originally on the 4 cylinder to operate the heavy clutch on the NV4500. I've had this jeep for probably 10 years and I've been through at least that many clutch slave cylinders because one blows out every year.

I either need a part number for the baddest direct fit slave cylinder on the planet or I need some advice on how to convert this thing to a manual clutch.

By advice I mean step by step instructions as if you were talking to a two year old.

I know I haven't been around in a while and I know this isn't an early CJ question but I would really appreciate some help.

Thanks very much in advance.

 

Adaptor kits are available. Try googling.

For instance, Novak. <http://www.novak-adapt.com/catalog/clutch/kit_hcr3.htm>

 

John, This is always an interesting subject when Hydraulic's & Cutch & Slave cylinders are the Topic since there are many, many varibles :

First off one has to understand the complete system..........from the pedal , its related ratio to the clutch Master cylinder, the size of the bore in this cylinder, the size of the slave cylinder and travel needed at the clutch fork and throwout bearing to accomplish full clutch release................Most Jeep systems had a 13/16" bore Master and a 7/8" bore slave..........Note: Smaller bore = more mechanical pressure but less fluid or volume transfer versus Larger Bore = less mechanical pressure but more volume.
So if your Happy with the force needed to apply the clutch and the travel at the fork is Ok to fully release the clutch.............I would as a prior member has suggested go with the Novak Slave.........This is a product that is built in house has more travel than any other slaves on the market and is rebuildable...........this slave is available in either 7/8" or 3/4" bores and should be matched to your Master cylinder to get the required amount of fluid transfer you desire.
If you are having to replace these Slaves yearly as you mentioned it almost sounds as if you have a system that is not sized correctly for the amount of work it's being required to do............

 

Tarry, I don't think it's John's fault.
The factory 4 banger clutch master cylinders used in the 80's were leakers when brand new.
Jeep blamed it on folks/dealers using the wrong brake fluid.
TSB for when changing clutch master cylinder, supply line and slave cylinder if I recall.
Seems we had to use special Girling brake fluid or something like that.....factory BS.
Anyway, John should just ditch the factory Jeep cylinders as already mentioned.

 

Thanks tary...I think what's happening is the slave is overextending and the bore, or piston as I'd call it is being pushed out of the slave. I hadn't really understood that until this particular time when it actually pushed outside so far that it sort of got cocked to the side and wouldn't go back in. My clutch was just locked. Not sure how to say that but my clutch was engaged and would not release because the push rod and piston of the slave wouldn't go back inside.

I had to get under the jeep with a screwdriver and hammer and tap on the side of it till it lined back up and popped back in.

I'm gonna try Novak and see if I can explain my issues over the phone and maybe they have a better slave cylinder. I like the hydro clutch. It operates very smoothly when it works. Just tired of it blowing out every year and putting me in the shop and trying to locate another slave and all that jazz. I just want to fix it and be done with it.

 

John, I'm glad I did not confuse you as I sometimes can..........although the systems are normally very simple, at times they can become quite complex. But if you follow the rules of Hydraulic fluid volume transfer it is fairly simple.
If your having issues with the piston coming so far out of the bore that it can become cocked in the slave cylinder then , I would agree that a longer stroke Slave is in need................The Novak as I mentioned earlier has the longest stroke of any on the market about 2 inches total while others are only about 1.5" including the Willwood version...........talke to those guys in Utah they are very knowledgable. Terry

 

I don't remember if these have an adjustable slave Pushrod or not. If so sounds like adjustment may be off and it is adjusted too far out to begin with causing the piston to run out of travel.
Another option may be a slave with a larger bore to reduce travel if you have too much now. This will reduce pedal effort though which may be good or not.
Is the mc a stock Jeep part or something else? If the slave and master are matched factory parts something is suspicious here.


Sent from my iPhone

 

I use a 80' CJ Hydraulic clutch and have never had a problem with the slave cylinder popping out or leaking. My question is. How is the slave cylinder mounted? The bracket could be flexing enough to allow the piston to pop out.