Hey all,

Today I aquired a 96 XJ - I've been waiting for a cheap one and got it. But - it needs work. Body is good, no rust up top with a little under the back doors which I understand is somewhat common. Oh, sport model... interior is messed but I'm not caring much about that.

So... the work. I did not notice when I bought it but the fuel pump started humming. Seems easy to fix if I need a new pump - don't even need to drop the tank. Anyway I can test it or should I just get a new one and replace now ?

Second, I can't get into 4 low - no idea about 4x4 stuff so I'm clueless on that. EDIT: Woops. If I move the trans to neutral I can get to 4L no problem. Sounds like a problem between seat and wheel. lol

Now the bad part...it's overheating. Oil looks clean, coolant has no oil but I'm worried it could be the head gasket. Are those hydrocarbon testers that attach to the rad worth the $40 ? I understand that is really the best way to rule our head gasket.

If it's the head, get ready for a flurry of action shots

Thanks for your advice... I think I'll be here a while

 

Welcome to the forum. Are u sure there's no coolant leaks from anywhere? Hoses, radiator cap, water pump, thermostat housing? Etc

 

Welcome

 

What makes you think it may be the head gasket? Under what conditions is it overheating and how badly?

 

Well, I don't think so but will look more. I'm thinking since the overflow tank came up high the pressure must be ok? Does that make sense or is my ignorance showing? I'm hoping it's just a cooling system issue so I pulled the plug on the rad and drained a couple quarts for inspections. Clear(ish) with some particulates. The fluid at the top of the rad looks much more greenish. I think a flush is a good idea.

 

Thanks!

 

Overheating when doing any driving at all and up to about the redline before I shut it down - 114C (~239F). It will cool down a bit at idle (or down hill) but that's it. Also, the valve cover cap and down is a bit of a mess. That could just be the valve cover gasket I suppose.

To be honest I'm not sure. I just don't want to start replacing random bits if there is a simple test I can do to rule something major out. Also don't want a cracked head if I can avoid it

 

Dang! Helluva way to start out with your Jeep...

You will get some other good advice and hopefully a magic solution for the over heating but depending on what you know about the maintenance history, I don't know any way to go at this but with the classic heavy duty flush, replacement radiator cap and thermostat and check of fans and pump.

Always good to go ahead and get an IR thermometer and confirm that your gauge is accurate as you work on it.

Good luck!

 

Yep... but it will be fun I think. Thanks... I can't wait to start some serious playing

 

I also have a '96, the pump does hum just a bit. If your carpet is missing in the back you'll hear it pretty well. Really no way to test it other than a fuel pressure check.

The combustion gas test kits work pretty well. However if your head gasket were leaking badly enough to cause that sort of overheating you'd probably notice other symptoms too. They might include oil in the coolant or water in the oil, disappearing coolant, bubbles in the overflow tank, coolant shooting out the overflow tank, steam from the exhaust, coolant residue in the tailpipe, misfires, plugs that look steam-cleaned... any of that stuff going on?
Assuming you've verified the fans operate, I'd do a flush and thermostat change to start. If that doesn't do it, pull the water pump. Depending on what the PO ran in the radiator and how well it was maintained, the pump may have no impellers left.

 

A headgasket would be the last thing I replace unless a compression check tells you otherwise. My radiator was half plugged with stop leak and my heater core was FULL of it as well... TWICE I had to flush the core because of how much crap was in the cooling system. Had to take my head to the car wash to pressure wash it so I could get all the stop leak out of it. The impellers on my pump were razor blades from pumping an abrasive fluid for so long.So when over heating, I'd replace my water pump, thermostat, and fan clutch. If that doesn't solve the problem, do a compression check and you will know from there if it's the HG or the radiator.

 

Thanks - this morning a flush in on the agenda with a new rad cap just in case.

 

just food for thought. a compression and/or leakdown test is certainly cheaper than replacing any of those parts and will give you solid info you need to know anyhow.

a leakdown test will tell you exactly what's going on with the engine.