-overheating-

[neal t gilbert]

I took off all the smog stuff-I capped and pluged-replaced the heater fitting,and when i was done,i kept my inside things working,a/c-cuise control-etc-.........The problem is it seems to overheat and build presure......So i replaced the water pump,and all other coolant related things,Still have the problem.....Any body got any ideas.....One guy told me it has to do with a vacum control that i replaced going to the heater core......

[trickc]

Neal if I recall yours is a later model, that would've come with some cto's on (coolant temp. overide) some of those may be necessary for the system to function properly.
Also,radiator been replaced or rodded and re-cored? Fan shroud in place?
If I read correctly you've bypassed the heater core? I believe its essential also for the cooling system. Sorta a mini radiator.

[neal t gilbert]

yes it is a 1989 GW the heater core is still in line,the fan shroud is still there,the only thing I haven't done is the radiator,I tought it might have been something else-it was cooling fine before i done this... thanks neal

[trickc]

when you ripped out the emission stuff, are you sure you got all the vacuum stuff plugged, if you got a vacuum leak it could cause a lean condition in which it would run a little hotter. just a thought.

[Bob Barry]

Plus if you've disconnected the EGR, your running lean and running hot.

[JeepFreak]

I agree with Bob...I did this to a Cherokee I recently purchased and from what I gathered the 2150 tends to run a hair lean anyway. After removing all the emmissions I simply drilled the jets a few sizes larger and problem solved (plus it runs a whole lot better too).

[JeepFreak]

Also I might add that I took my carb apart several times to re-drill the jets and I finally found a 1/16 bit gave me a real nice mixture. Lots of guys will say not to use regular drill bits but if you are careful you can get nice smooth jet walls when drilling. Might save you some time. If you removed the emmissions you will have to richen the carb or you will ping and run hot. Neither are conditions you want.

[ May 20, 2003, 09:53 PM: Message edited by: JeepFreak ]

[billyrb]

Is there a way to test CTO's to ensure they are operating properly?

[The Anti-Chrysler]

If you've replaced lots of parts in the cooling system, and drained and refilled, it's very likely you have air pockets inside the system, making it overheat. I would try taking off the thermostat side of the radiator hose, and holding the t-stat open with a screwdriver, and making sure the coolant is full underneath. If there's air built up under the thermostat, it might prevent coolant reaching the thermostat allowing it to open. I've seen this on several ocasions where major cooling system work has been done.

I tend to discount fuel / EGR problems and the like, after you described "building pressure". Air trapped in the system will cause excess pressure to build up.