Looking for a ZJ prop valve

[Oatmeal]

Interesting.

How different are the plungers/endcaps? Could one get away with triimming a loop off of the spring?

The ZJ spring is stiffer so, it sends more pressure to the rear before bypassing. I couldn't really tell the difference (casually looking at them) in plungers but, you can feel a significant improvement (to me, anyway) in braking with the prop valve upgrade--------Hans

 

[OverlandZJ]

The ZJ plunger has a smaller OD at the endcap side. Theres a seal on the endcap that should grip the plunger tightly.

In this pic it's a ZJ plunger in an XJ endcap, you can see the plunger not sealing tightly as it doesnt sit at 90*.

Here is the ZJ plunger with a ZJ endcap, notice the tight seal on plunger holding it at 90*.

I noticed this when i did my booster/ZJ master cyl and prop valve swap, figured it was tight for a reason, so i made sure i kept it all together.

 

[XJEEPER]

Overland, just to clarify for the masses, did you install the ZJ plunger, O-ring and cap into your XJ prop valve housing, or did you swap out the whole assembly? (ZJ prop valve replacing XJ prop valve)

 

[OverlandZJ]

X, i swapped the ZJ endcap,plunger,spring and o-ring into my XJ prop valve housing.

Keep in mind the parts pictured came from a 4 wheel disc ZJ prop valve. Cal, i'm betting the ZJ and XJ props are the same part# if the ZJ has rear drum brakes.

 

[Clean Racing]

Ok the part numbers are not the same for the xj/zj.. Here is the break down..
5200 6221 XJ w/o abs 87~90
5200 6394 XJ w/o abs Up to 3-1-93
5200 9108 XJ w/o abs After 3-1-93
5200 8133 XJ w/o Police package up to 3-1-93
5200 9110 XJ w/o Police package after 3-1-93
5200 8121 XJ w/Police package up to 3-1-93
5200 9112 XJ w/Police package after 3-1-93 10" rear brakes
5200 0097 XJ Venezeula
5200 8650 XJ 9" rear brakes LHD 1994
5200 8035 XJ 9" rear brakes LHD 1995-96
5200 8651 XJ 9" rear brakes RHD

5200 9113 ZJ 1993 with rear drums
5200 9129 ZJ with rear disc brakes 1994
5200 9061 ZJ with rear disc brakes 1995-96

That is all the info I have collected over the years.. and there is a difference. I run the WJ booster/Master and a 95 ZJ prop valve with WJ brakes front and Explorer brakes rear.. It is a well balanced set up..

 

[gorman]

I got my full WJ setup (booster, mc, prop valve) on ebay. The whole setup with shipping was less than $30.

What does the WJ prop valve look like? I thought they had EBD, or that only for emergency braking?

I'm in the process of fitting WJ knuckles and brakes up front and will be running WJ disks in the rear with Ford Sapphire calipers (same as the Merkur Scorpio in the US). These rear calipers are the ones with closest piston size to the WJ rear calipers I could find which have the emergency brake working off the caliper. If I can find a WJ prop valve to work with this setup it would be great, but the junkyards I've been to had no prop valves for WJs.

 

[Nuke Proof]

Thanks for the help again guys, I'll grab a booster and MC on car-parts.

 

[lifted00]

I did the disc swap from the liberty and the rears did not work as well. I just got thru swaping in the internals from the ZJ P valve. All works great now.

 

[altierior]

is there a check valve in the master cylinder? has anyone tried removing the check valve from the master cylinder in lieu of swapping out the prop valve?

 

[89xj]

is there a check valve in the master cylinder? has anyone tried removing the check valve from the master cylinder in lieu of swapping out the prop valve?

how would that change the line pressure coming out of the prop valve or even the pressure from the master?