Is there a way to check to see if the pump is functioning?
I pulled the big hose going into my thermostat today to make sure it was functioning and no water was being sent through it. The jeep was warmed up in the driveway. Its a 2000 with a 4.0 and 4wd.

Okay, So earlier this week I had some overheating problems with my jeep and had it towed to a shop and they diagnosed my jeep with a blown head gasket. I accepted their diagnosis and had it towed home to work on it myself. So after a long week of finals at school and work I now have the time to check it out.
I still do not see any water in the oil. I thought there was always an obvious amount in the oil if you blow the head gasket. Then my dad checked out the water pump and we couldn't figure out how to make sure it was functioning. I am going to replace the t-stat and would like to know how to check out the condition of my water pump. Thanks in advance.

 

You might as well replace it if you are having heating cooling problems..real easy to do on xj.

Head gasket?...how was it running when ovwrheating?..also..is there any water/coolant in radiator?

 

There is always coolant in it. I keep a pretty good eye on things so that I could notice anything out of the ordinary.
The night before it overheated, the temperature got pretty high for about 15-20 seconds then lowered right back down. Then driving it to work the next day it was slow to warm up then it just started climbing towards the higher end of the scale. I limped it into work and let it sit for the next ten hours. I got off of work and apprehensively started her up and there was some white smoke coming out the tailpipe. I limped her around the corner,to the shop, never had a chance to get up to temperature and dropped her off there for the night. I started it up this morning and I can't really see anything like coolant everywhere, or anything leaking from the heads. Is there any surefire way to be positive the head gasket is blown? Or to check if it could just be a bad water pump t-stat?

 

sounds like possible thermostat issue

 

Remove this heater hose at the firewall, fill the cooling system and make sure the hose is pointed down at the ground (away from u or others). Start the motor.....for a few seconds u should have a fire hose if the pump is working well.

 

A bad head gasket doesn't always mean there is coolant on oil. Just depends on the place the head gasket is bad.

 

i am leaning toward the thermostat 2... have you ever changed it? it is also cheaper and does control coolant flow...

 

It does sound like a gasket issue- the white smoke and all... But I think it's been stated that I depends on where the gasket is leaky/blown..
It got up to temp, began to overheated, thats when issue started- drove to work and it overheated again- it sat for 10 hours- drove it to shop, it sputtered with white smoke- parked it, checked fluids, no visible contamination? So enough coolant got in before you parked it for the 10 hours that when started, it burned off what got in and probably didn't heat up enough to let in more (or at least enough) coolant that would show up when checked.... Idk, running thru it, this makes sense to me. Double check the pump and all, but replacing the head gasket is probably the way.. My .02! Good luck.

 

have you done a compresion test? that might give you a idea if you have a bad head gasket...

 

Thanks for all the replies.
I drained the oil today and my father nor I could find any visible contamination. We've let it warm up, until it reaches 210 ish on the dashboard and pulled the big hose off of the t-stat housing and it was bone dry. We went down the street to the auto store and got a new 195 tstat and now we have water flow. So maybe this was it all along? We are having trouble getting the new tstat sealed correctly. I was reading up on some other posts and I am not the only one that has had problems getting the gasket to line up and seal properly so that pretty reassuring. Its dark now and I will be back at it in the morning to see if I can get that thermostat housing on there correctly so it doesn't shoot water all over the place.

So if it were a head gasket I would have contaminated oil right?
Hopefully things go a little smoother tomorrow and I really appreciate everyones insight on my problems, thanks again.