YJ Vaccum hoses question

[thelabrieski]

Hey guys let me give you a run down, first off brand new to this forum thanks to hoobness to turning me on to it. I bought a 500.00 bargin YJ in pretty good shape but the vaccum hoses were all messed up. I have(or at least i think i have) figured most of them out. I have some questions about what some of the extra stuff that wasent plugged in when i got the jeep is/are? I have some pictures of this stuff, can anyone tell me what they are and how i can connect them into this system. Also i can't located any of the Pulse air system things, or the Decel Valve, does anyone have any pictures of the devel valve and where it is located. So anyway onto the pics:
photo "a" is a blue sensor on the firewall near the battery, http://pg.photos.yahoo.com/ph/seanlabriestrips/detail?.dir=ec4c&.dnm=c564re2.jpg&.src=ph
photo "B" is a vacuum valve thinger attached to the wiring harness with a blue wire over by the battery http://pg.photos.yahoo.com/ph/seanlabriestrips/detail?.dir=ec4c&.dnm=cf70re2.jpg&.src=ph
Photo C is a vaccume tube without a valve thinger that disappears into the wiring harness over by the battery, it loops uo and connects to the same T as the thing in photo B http://pg.photos.yahoo.com/ph/seanlabriestrips/detail?.dir=ec4c&.dnm=c7b3re2.jpg&.src=ph
photo D is a small metal thing connected to the wiring harness up behind the air cleaning, it runs along the center top of the firewall http://pg.photos.yahoo.com/ph/seanlabriestrips/detail?.dir=ec4c&.dnm=75a0re2.jpg&.src=ph

thanks for any and all info you guys can give me.

 

[lah2420]

"A" is a switch that turns on the 4WD light on your dash when you pull the tcase into 4LO or 4HI.
"B" looks like a vacuum check valve. The blue wire is probably a vacuum line.
"C"-- I have no idea. Unless this was the previous owner's way to fix a vacuum leak when he disconnected lines.
"D"-- I don't see one on my '87. It looks like a vacuum switch of some kind. Possibly something to do with the carb since it sounds like someone disconnected all the pulse air stuff.
Look at the front axle on the passenger side. There should be a connector with 3 vacuum lines on it. A black, yellow, and green. If it isn't there, and a cable is there instead, the previous owner has installed a manual locking system on the front axle. That would explain why "A" is disconnected and "B" looks like it does. My blue vacuum line has a check valve on it that just hangs down disconnected.
Crude diagram attached below
Good Luck.

 

[thelabrieski]

Thanks, I've since figured out where the decel valve is as well. any idea where i can buy all the factory vacuum hoses and "T" connectors? i have this whole system peiced together

 

[90growler]

Where did you find a $500 YJ? Was it running? I want one of those..............

 

[Bounty__Hunter]

Pic B, there should be no vaccum line connected on the end you have the T connected to, that's a vented vacuum line from the transfer case vacuum harness.

 

[Sparky-Watts]

Where did you find a $500 YJ? Was it running? I want one of those..............

Dang, me too!!:shock: By the way, welcome to Jeepz!! You'll find tons of information here from our Audience of Experts (I'm not one of them), as well as lots of good company. You'll be glad you stopped in, and we'd be glad if you stuck around! 8)

 

[LRwrnglr]

"C" is just a check valve. It lets vacuum in one way but not out the other.

I don't know if yours works but on my YJ it didnt work after I put my lift on so I had to divert to a homemade posi-lok. works pretty slick. But anyway WELCOME!!

LR

 

[thelabrieski]

Ok, thanks for the help so far guys, you've all been great. Let me give you an update based on that rough diagram that Lah2420 drew for me. The hoses in picture A2(green, yellow and blacK) all run into a wire shroud and head up towards the firewall along the fender, in picture B2 you can see that the yellow hose runs into a check valve and then on the other side of the check valve it turns into a black hose which in turn connects to a T junction along with the random hose from original picture C which runs into the T juction along with the blue hose and check valve that is supposed to be plugged into nothing. There is also a red hose that comes up from the transfer case(I can't tell if it is plugged into the transfer case or not) and attaches to a vaccuum hose coming from the tank under the battery. Can anyone tell me if any of these sound like they are plugged in correctly, also can anyone tell me how their hoses are conencted into the system. On the diagram that Lah2420 drew does anyone know where the red hose is supposed to plug into the carb? i can't find one plugging into it(maybe that is the red hose from picture C2?)

and to answer questions, no the 500.00 jeep was not running, it had a flat tire, is missing every single screw that holds the dashboard together, and the horn will not turn off, the water pump was busted, and all the vaccuum hoses were screwed up, but other than that she is fine.

 

[Bounty__Hunter]

Of the three hoses coming from the vacuum disconnect on the front axle, one should run to the 4wd indicator light switch on the firewall. The other two should go to the transfer case along with the red and blue vacuum lines. The blue is the vacuum vent line for the transfer case and the red is the vacuum supply to the transfer case.

 

[thelabrieski]

so it really shouldn't matter where in the vacuum line system the red one plugs in right?

 

[lah2420]

I looked and my red line doesn't actually run to the carb. It "T"s into a line from the manifold vacuum port under the carb. This may not be stock as my Jeep was very worked over when I bought it. The drawing is one I had copied from someone else's site. From there it goes to the transfer case. If you can make heads or tails of it, here's a supposedly complete YJ vacuum drawing.

 

[Bounty__Hunter]

The red line needs any manifold vacuum.

The above vacuum pic does not contain any lines for the CAD (Central Axle Disconnect) system.

 

[thelabrieski]

there is a line coming from the vacuum reservior that leads to the Vac SW idle/decel switches. the red line is T-ed into this line, should that be OK?

also can i access the transfer case lines by removing the shifter boots from the shifters?

 

[lah2420]

The red line needs any manifold vacuum.

The above vacuum pic does not contain any lines for the CAD (Central Axle Disconnect) system.

That figures. I'm always a day late and a dollar short. Now some of my parts are even nonexistent.

 

[hoobness]

hey , ryan from VIP. glad you found the site. there is a wealth of info here, which i see you have found. I have found over the years the members here are always happily willing to give any bit of info they might have to aid you in the right direction. Keeps me in touch...
about that weber.. collins bros is where I got mine from, but you can find them anywhere - just look - ask questions here... most importantly SHOP AROUND. prices will vary greatly, collins bros 2 years ago was the cheapest i found...

good luck

 

[Bounty__Hunter]

there is a line coming from the vacuum reservior that leads to the Vac SW idle/decel switches. the red line is T-ed into this line, should that be OK?

also can i access the transfer case lines by removing the shifter boots from the shifters?

You can access them best from beneath the jeep, reaching around the transmission crossmember.

Pull the two similar vacuum lines from the front axle and check for strong vacuum. Vacuum should alternate between the two depending on if you're in 2wd or 4wd.