I've Been Wrong ,,,before But Never This Long

today I went to pull my master cyl apart to take out my drum brake 10lb residual pressure valve ....and I see my brake lines are reversed at the master .... I bought the jeep in '90 and have changed masters before but didnt know .....the first port closer to the plunger is going to the brake line lock then the
distribution block and then to the rear wheels .....I looked at my manual and that port goes to go to the front .......this is the normal frame mounted dual master cylinder

...EDIT .... so I switched the lines around and now waiting for the new 2 lb RPV to be bought .......this is taking for-ev-er

 

Let me explain this cause I went thru this years ago (2005) when I installed my dana 30 and disk brakes. The factory dual port MC has the front port hooked to the front brakes and the rear brakes hooked to the rear port. There was no proportioning valve in the original system and the rear brakes had smaller brake cylinders than the front did along with a distribution block with different sized ports. The MC also has a stepped piston with the smaller fluid well in the front and the larger part of the piston with the larger fluid well in the rear. This worked fine with the lines and brake cylinders matched to the original setup but was wholly insufficient when you coupled disk brakes to the system. You then need the larger volume of the rear piston (and fluid well) pushing the front brakes due to the larger volume the disk brakes need to function.
When I hooked mine up just the way the factory had it, my disk did virtually nothing, swapped them around and they worked fine.

 

well
I'll just have to see what happens
I always thought stopped ok with the lines backwards with full 11" drums
....

 

this pic is not mine .........so the rpv I bought is pipe thread with no seat in it for the line that means I would have to buy a fitting to adapt and wrap Teflon tape .... sounds like a bad plan right ?

 

Use lock tite instead of Teflon.

 

Yeah, the ones i got were pipe thread too. I had to buy the brass adapter and use teflon tape. It didn't work as well as I wanted. I also think it was a source of very slight air infiltration and fluid weep that required me to bleed my brakes every month. I redid my brake system with a vacuum booster, no RPV's and no proportioning valve. It works great for me.

 

Seems counter-intuitive that someone would even market a part, designed for use in a brake system, and not make it to accept flared lines. Or is it just me?

 

Use brass npt to fllare fittings and a good quality thread sealant like Rectorseal. Don't use locktite, it's not a sealant and Teflon tape is not needed with brass fitting when using a good Teflon based thread sealant.

 

Here is my setup. Wilwood 2lb residual valve for front and 10lb for rear. Wilwood proportioning valve plumbed in. D30 with discs up front and D44 with 11" drums in the back. I also removed the built in residual valves from the MC.

 

so I popped out the brass fitting and there was no rpv's.. on either side !

 

Well this made me look at mine. and yea dana is piped backwards also! Thanks Spider. Crap now i have to repipe stuff also

 

hehe ....yeah I knowJim it sucks SWAY stopped fine I thought .

 

Mine is also piped backwards - we should start a club.
It's on the list to change.

 

I love my 2A single reservoir master cylinder.

 

Me 2.

 

I'm telling you these are not actually piped backwards, thats how all of them were plumbed from the factory.

 

with full drums?