huge problems on the 4.0 NEED HELP

[sahara0207]

:dunno:
so yesterday we were ganna go wheelin at bald and try out the new steering set up and i pull out of my nieghbor hood and go two blocks before my radiator exploded!!! it wasnt even up to 210 yet? and so we find the huge crack on the very top plastic. the only visible part.

we then go and get a radiator patch and some jb weld and go to town.... then we leave it and go to the mountains and i rode with a bud. later we come back down and fire it up and the crack is sealed. on the way home i make it a block and pull up to the stop sighn and my jeep turns off? wont start after toyin with it we get it to start and go. get home and it does it like 50 feet from the drivway.... but this time the engin compartment started smokin and it was really bad. open it up the actuall engine is smokin! so we push it home....

by the way all of a sudden my dash lights and spedo didnt work that day?
]
lots of bad things in one day? i just can not beleve it...

[sahara0207]

im thinkin i blew a head gasket? what you guys think?

[igofshn]

Check the oil, if there is water in it then you probably did blow the head gasket. did it ever over heat???

[sahara0207]

thats the thing.. both time the engine was only on a couple of min...? only up to 210 the first time (radiator) then 180 second time on engine?

[RAT]

You said the radiator blew. Are you sure there was coolant in the engine?
Did you make sure there was enough coolant in after the repair?
Did you notice coolant on the ground under the Jeep when it was sitting. If the there was enough pressure to blow the radiator, there may have been enough to blow a freeze plug.
The water pump may not be pumping.
Thermostat may be stuck shut.
Was the engine running fine before the radiator blew? If you blew a head gasket, the engine might have been running weird.
Time for a cooling system pressure/leak down test.
You know how to tell if the water pump is pumping? Take the radiator cap off (cold engine please) and start the engine. The water pump has a bypass, so you should see movement in the water inside the radiator pretty soon after you start the engine. Don't look directly into the radiator, especially after the engine heats up. If you don't see movement within a minute or two shut it off.

good luck

[sahara0207]

ok so after fixing the leak i had filled it with fluid again.... thermo stat might be trash... the engine ran great till the radiator blew. nothin odd no noises. only wird thing was after the radiator blew befor the engine did was how it turned off.... it did feel weak and like their was low compression?

ok rat thank for the help i was thinkin first to check for water in the cylnders to be safe.. remover sparks and turn key look for water....

then check preasure on cylinders...

then ill check to see if the pump is working

[Shadly1]

remover sparks and turn key look for water....

I don't think you'll find it like that. If you have water in your oil, you'll probably see it on the dipstick... look for chocolate milk. If you have oil in the water, it should float to the top if you leave it alone for a while and you'll see it under the radiator cap. If you're burning oil, the exhaust will be blue. If you're burning water, the exhaust will be white. All signs of a head gasket.

If you suspect a thermostat, replace it. Sure, there are all sorts of tests you can do to make sure it's functioning properly but it's a cheap part. Just do it so you can rule it out. If you cracked plastic on your radiator, chances are you're not going to be able to seal it for very long with glues and epoxies. I'd replace it with at least a used one from a junkyard, if not a new one. A radiator shop might be able to replace the whole end cap, but that's hit and miss a lot of the time to find a reputable shop.

[maddmike]

you can also just take the thermostat out and run without it while you're troubleshooting if you don't want to get a new one. they are designed to fail in the open position and although this does not always happen it is a second way of isolating that part from the rest of your problems. i've also purchased a new thermostat that didn't work so there you go.

i can't really help much with the other troubleshooting but will agree, start over fresh checking all the fluids before you turn on the rig and then see what happens. note the exact problems, sequences, time lapses, etc. next time and that way whether you post an update or bring it into a shop you can hopefully find someone that can isolate the problem accurately so you don't have to make repairs twice.

best of luck.

[sahara0207]

THANKS GUYS! and ya im takin the coil wire off. starter is all that will turn the pisons. but if any water is in the engine i dont want it to try and compress it via no sparks. ill drain fluid too... right when i figured out the front streach

[flatpoint]

A cracked head will act like a blown head gasket too.

[Shadly1]

Whatever it is, sorry to hear it. If I was near Fresno, I'd do my best to get you in the dirt again. Keep posting as you find stuff. It will help diagnose.

[sahara0207]

so today after work i took off the spark plugs and turned the key and no water came out so i then drained the oil and it looked great... i kinda wanted to put it back in! lol flet good too...

i put some new oil, filter, plugs and wires on since i was all ready messin around. tomorrow i will check on a new radiator and thermostat... so any suggestions on the thermo? like a lower temp one?

[Shadly1]

any suggestions on the thermo? like a lower temp one?

Nooooooes... stick with stock temp unless you really, really, really have a reason to lower the operating temp.

[Kodiak Spirit]

I ran mine without a thermostat for a while and then realized that with the fuel injection the engine was not getting hot enough for the right burn and I was losing power.

You can get a new thermostat and put it in a glass of water and heat it and watch it move at temp to know that it works before you put it in if you like.

as far as the radiator, I got mine frum Kragen, got the lifetime warranty, when the plastic tank started leaking (again) I got a new one for free and gave them the old one. keep all yer recipts... I haven't had any problems with this one yet, about 1-1/2 years now...

[sahara0207]

how much you pay for the thing?