Hey! Lower injector O rings. Spray some little shots of Quick start, (or water of you prefer), on there and see if anything changes. They are under vacuum, if you add something different and the engine changes, it's leaking. Btw, in that process it might be hard to tell if it is the O ring or the gasket sucking, as they are pretty close together.

Funny the way it works with pages. Ffriends, (and followers), see post #15.

 

Thanks DFlinstone! That gives me something else to try. I think I'm going to have a busy weekend working on it. But hey-I call it therapy!!!

Taz

 

Ok, update. I was able to get a bolt in the manifold that was missing, it helped about one-half. Idle ranges from 800-1500, 1500 most of the time. 1000 in gear. The foam in the radiator is still there but it slowed down, then almost quit. I let the jeep run for 30 mins or more at 1500 rpm and it never over heated, only got to 199 by laser thermometer. just a little under 210 on guage. No bubbles in overflow container. Keep in mind the electric fan is disconnected, so with it plugged in, it should be even cooler.

If you completely cover the throttle body and cut off the air, the engine still runs (smoothly) at 500 rpm, can't hear any air sucking sounds.

I had to order a chemical gasses tester from auto parts store, it should be in today. I will then test the coolant for exhaust gasses. keep in mind all cylinder compression tests were almost identical and well within spec, not bad for 237000 miles.

When I get the coolant gasses tested I'll update again. In the meantime, any suggestions;

Foam in radiator (smaller amount than before)
High idle
Why does it continue to run with air shut off from throttle body? I covered it with a block and sealed it off.
Wonder why it was overheating and now its not?

The "donut" on the exhaust is still loose bty.

Taz

 

Oh, I let it run with the radiator cap ON.

 

Update, I got my chemical gasses coolant tester, the fluid stayed blue from cold to hot, it never changed, even though some foam was coming out of the radiator top (where cap goes). I then went to the tail pipe just to make sure the device was working, and behold within two squeezes of the bulb the fluid was bright yellow. so at least I know that works.

That being said, compression is equal between all cylinders.
No exhaust gas in coolant,
tells me head and gasket is okay, right?????

foam may be just air leaking into radiator system somewhere, how do I find that??

Taz

 

Ive had the heater on most of the time, no water in the floor. Heater blows hot air.
I did put a gasket (a real one) on the thermostat housing, no leaks there now.

as engine warms up, the coolant overflows the radiator (with cap off) is that normal??

Taz

 

One of my first thoughts was you removed throttle body twice. New gasket?

 

no new gasket under throttle body. It stayed on the manifold in good condition. no tares no pieces missing. spraying carb cleaner around it had no effect, I don't think it is leaking much air there.

 

id say it was gettin hot so quick before do to the massive leak you had. it wouldve caused it to run lean which can warm em up quick and make em run hot. deff sounds like you still have a vac leak somewhere causing the high idle. try the spray test again following the entire system. the diagram should be on the drivers side firewall. as for the foam, if you have recently done coolant service, then it COULD still be purging air from the system. this will clear up on its own the more it is ran.

 

as for the electical problem, i would start be inspecting your battery terminals and cleaning or replacing them. and while your at it clean the grounds (at pass. front fender by battery, pass. side of engine block above oil filter, and the ground going from drivers side of head to drivers side firewall up top) it is common for these to get dirty and corroded (usually will throw high voltage codes on most sensors so is good preventive maintainence that doesnt cost a dime)

 

Thanks Jarred

 

update, i got a radiator pressure tester. radiator showed no leaks, cap is bad, only holds about 7 psi. when it cools off tonight i will try spraying carb cleaner around the exhaust manifold again and see if that is where air is leaking in still (high idle-1400-1500).

Taz