CTO alert! Paging Dr Barry, STAT

[bignblue]

I noticed today whilst (thanks, Paul--didn't want to be the first!) changing my thermostat that one of the lines coming off the CTO (I'm guessing that's what that yellow jobber is) was blocked with (SURPRISE!!!) a screw. What would this go to in a healthy Jeep?

------------------
'78 Chero WT
401/4bbl/TH400/BWQT
44s F&R
New leafs springs!!!!
no interior to speak of
"Jeep: the toughest 4-letter word on wheels"

[DerJeep]

bignblue,

If it has three posts then it is (1979 at least) the distributor vacuum advance CTO.

Top (1) goes to manifold vacuum (Same fitting for brake master)
Middle (D) goes to distributor
Bottom (2) goes to spark advance port on lower passenger side of carb, towards the front.

When the engine is cold it provides manifold vacuum. After it has warmed up, then ported vacuum.

Hope this helps.

Kevin

[This message has been edited by DerJeep (edited December 13, 2000).]

[Ralph]

Narnian, did you get that?

[bignblue]

The bottom (end of switch) hose on mine runs to a nipple near the base of the carb on the DRIVER'S side...is this way wrong? What's the difference between the carb ports? When I say 'bottom' I mean the far end of the switch, not the end that's attached near the t-stat.

[DerJeep]

Is the center nipple, of the yellow CTO switch, connected to the distributor advance? It should be.

The vacuum port on the drivers side, front of the 2150 carb is for the EGR valve (Not directly though. It goes to another two nipple CTO and vacuum dump, etc before hitting the EGR). The one on the passenger's side on the left side of the carb is for the distributor via the CTO.

1. Do you have a Motorcraft 2150 carburator?
2. Where is your EGR valve plugged in?

****************
Oops, brain fart on my behalf. Just noticed that you do have a 4bbl.

I do not know where the vacuum connections for EGR and distrib are on that one.
****************


[This message has been edited by DerJeep (edited December 14, 2000).]

[DerJeep]

If your distributor vacuum advance hose plugs into the yellow CTO, one nipple has a screw in it and the CTO is functioning properly, you are running without vacuum advance in either warm or cold condition.

[Narnian]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Ralph:
Narnian, did you get that?<HR></BLOCKQUOTE>


Yeah! I got that from WagThe78 a few weeks back. Made a big difference for the Pro_jection.

[reddog]

Do the "older" jeeps have the two CTO setup like my 87 with the "heavy duty cooling" option??

------------------
87 GW - Stock (but it looks like RiverBeast when I'm sleeping)
TFI upgrade
360,727,NP229

[DerJeep]

Reddog,

My 79 has heavy-duty cooling and has a CTO that will switch back to manifold vacuum if the coolant temp gets too high.

Mine has one three prong (yellow for distrib) and on two prong (black) for the EGR.

[bignblue]

All I've seen on my '78 is that one yellow 3-prong CTO, but I could be wrong. The middle nipple IS hooked up to the distributor, so that part's good. That's right, my carb is the 4350 so I don't know what plugs up where!

[DerJeep]

I'll look at my 79 TSM, this evening, and let you know. I doubt that too many changes were made in one year.

[Wagthe78]

This is how I'd do it.

See link.
http://www.ifsja.org/ubb/Forum2/HTML/001822.html

------------------
'78 wagon with 360,Holley TBI, 4-speed
"Built to Spin"
("to spin" as in "rotate motor",not as in "abuse Danas")

Open up the throttle and support an Arab!
Or better maybe
Plant a tree for every day we drive our rig! (maybe every hour)
Or still better, maybe
Build a still and make go-juice from those table
scraps that our moms made us forever feel bad about
throwing out!

[bignblue]

This may or may not be related, but I experienced something tonight for the first time ever! (no, not that) When I shut my jeep off, it died then immediately came back with a rev that ended in a series of knocks--kinda like a smoker shouting then hacking. What's up with that? My idle has been high all day, and I have to bump the pedal to bring it back down (which doesn't always work). Fixing my vacuum leak did THIS?

[Wagthe78]

If you have your vacuum advanced too far, maybe because your advance wasn't hooked up right and working. The Cylinders could be running hotter than normal causing the plug to allow for aferrun. Dying and knocking is due to the ignition not being on, so it can only do this for a moment. Revving, hmmm, are you running sort of rich, too?

Weird problem. Make sure all your vacs are right and set your timing correctly with vac hose plugged at dist. Check my link, the #4. of my reply. I know this is the correct connection, and the only difference is that you will hook up to your carb's ported tube, where as I hooked up to the Holley ported vacuum tube.