What Holds Vacuum? Some CTO ?s too

[Marty Sells]

I have an '81 Cherokee with AC so it should be the HD cooling version. PO totally hacked the vacuum hose setup. I made major progress tonite on it and have some ?s:

Is the thing with the green cap, mine says 3233991, the non linear valve? Which ports should hold vacuum? When I apply vacuum to what I believe is the manifold vacuum connection it leaks down in about 1 second.

Exactly which connection off the red CTO goes to the distributor? PO had nothing connected to the distributor so I had to make an educated guess based on the FSM. I picked the middle-ish one but they're not really aligned vertically. Answer I'm looking for might be something like: not the one on the top right and not the one at the bottom middle.

The 5 port HDC/CTO - is this the 5-port b/w
115deg one? See CTO web page (http://home.off-road.com/~wagoneer/tech/cto.html) for what I'm asking. Mine has two dots on the top that make it sort of black+white (certainly not orange!). Can I change the CTOs and only drail 1-2 gals of radiator fluid?

What on the CTOs, reverse delay, EGR valve should hold vacuum? I presume everything that's connected to majifold vacuum should hold vac.

If I have an aftermarket air clener where should the oil filter cap vent be routed? What should I do with the EGR temperature vacuum switch (TVS) since I can't put it in the air cleaner.

Regards,
Marty.

[Kimbrough]

Hey, another Georgia boy! smile.gif
You have a lot of good questions, none of which I can give a direct answer to. I hate seeing anyone's post go unanswered so here's a few links that might help: http://www.ifsja.org/tech/fuel/index.shtml
and: http://home.off-road.com/~wagoneer/tech/index.html

Good links to have at any rate.
Look at Bob Barry's site for a vac diagram of your rig's year.
A CTO is either manifold or ported vacuum, depending on the water temp in the motor - it is a temp-controlled switch.

By the way, some of us are going wheeling near Ellijay, Ga. Wanna go?
Look at Events to check it out and reply there. Thanks!!!

[ January 12, 2002: Message edited by: Kimbrough ]

[Ernzo]

Some time back, I downloaded a vacume diagram here, it may still be available with a search, ot you can email me and I will send it to you.

It REALLY helped me, although it is for a later model, I am sure it is very similar.

My Haynes manual also was a great source. The non-linear is a little disk deal looks like a tiny spaceship, I relaced mine. I would simply block the Air Cleaner ports that control the air supply. There are several one-way valves as well, these were a little hard to figure, I had to suss it out as the diagram was not clear on which 'way' the 'one' would go.

The dist connects to the middle port on mine.

The neat deal was that with all this vacume work, I also replaced hoses which was real helpful.

I drained one gal of coolant for a thermostat, I assume that the cto would be real close to that. There is also a great CTO page available here with variuos price comparrisons. I believe it is called

Jeep CTO Switch Interchange Chart

Luck,