AHH Jeep leaking coolant

1998 XJ Sport, Automatic 107,xxx on clock.

Yesterday while loooking for a parking spot at my school, the xj beeped at me and the instrument read "CHECK GAUGES". Turns out the XJ was over heating because the temp was reading like 250 or something. Anyway, I came home and left the xj sitting overnight. Walked out to the Jeep this morning and the damn thing spilled coolant all over the place along with some RUSTY fluid. All coming from somewhere on the driver's side. So I opened up the plastic Coolant resorvoir it was totally empty and had some rust build up on the bottom of the tank.

I thought it was a loose clamp somewhere but how could it let out the whole thing?

I'm going to try and find the leak but so far I had no luck with it. Any ideas would be appreciated.

#1Try to get everything dry & re-fill it with water. Look closely for drips.
#2 Driver's side, it could be at the pump or at the lower radiator hose. I think everything else is on the passenger's side on a 98.
#3 the rust colored liquid is probably coolant with a lot of radiator-buildup in it.
#4 Is it an option to have the thing towed to a mechanic who can pressure-test the cooling system? That would show you where the leak is, at least...

The engine could have been running hot but just short of the boiling point of the coolant mix. After you parked it, the coolant isn't flowing anywhere and there is no airflow but the block is still hot - the whole mess bubbles over from the radiator cap. Sounds unlikely but I have had an old pickup do it to me...

Hope something here proves helpful...

I just wiped everything with shop towel and I think I foudn where the leak is coming from. I THINK it's the radiator and the hose area. Probably some sort of seal because everytime I wipe the thing down it immediately starts dripping again. Exactly where the radiator and the hose, seal is..

You may have found the leak already, but I just replaced my water pump on mine and the leak looked like it was coming from where the lower radiator hose connects to the pump, after more looking I realized it was the pump. Sometimes the house get so thin and old from the inside out that it may be where its clamped to the rad on the far driver side.

found a pic! Could this be the water pump?

blackhawk411 said:

found a pic! Could this be the water pump?

Click to expand...

Yes, you found a pic. However, that's not an XJ setup. Notice, there's no overflow tank/bottle, it looks more like a CJ/YJ settp.

The water pump is item #7, if that's what you're asking.

You need to dry it off and see where the leak is coming from; there are too many possibilities to simply guess at. Don't forget that failing water pumps will weep out through a small hole under the nose of the pump, but your problem sounds much bigger.

Jim www.yuccaman.com

No that is not what I'm asking...the part where I circled red is where the coolant is leaking from. So that's most likely the radiator taking a dump right?

In that case it's either the radiator, the fitting, or the hose. Sounds like it's right in that area, but it could still be either the hose or the radiator.

I wouldn't recommend Stop-Leak type stuff... radiators.com has replacements and I believe there's a discount for members.

Jim www.yuccaman.com

It could actually be a number of things.
Bad hose, bad water pump, bad radiator cap. bad fan clutch, stuck thermostat stuck closed or partially closed. How long since you did any maintenance on it ?
You can refill it with water for testing but once you find the leak drain the water and refill with prestone green and DISTILLED water.
Personally I would replace the following, Thermostat [overheating damages them], both hoses or all the hoses including the heater hoses, you socal types tend to forget all about heaters , also the radiator pressure cap then go from there. Even though you live in socal you still need that 50/50 mix of coolant, it has corrosion inhibitors and lubricants that the system needs.
As for pressure testing the system, you can buy a Stant kit that has the pump and adapters for testing pressure as well as a cap tester for around $100 at most parts stores.
One thing I can say for mine stuff, I've never gotten any rust out of it, other glop but never any rust. That screams 'ignored maintenance' to me.

The Jeep was neglected big time from the previous owner. Right when i bought the thing, the freeze plug blew out (mind you this happend in summer in SOCAL). Took it to my mechanic and he said the radiator was rusted to death. But at the time I had to pay tuition so he recommended that he'd just flush it until the rust was gone...that's the story of that rust.

I'm thinking about replacing the radiator with the one from DPGOffroad.com and all the hoses and clamps as well as the radiator resorvoir which has a ton of rust build up on the bottom of it. HOPEFULLY that will fix the problem, the thermostat has been replaced less than 8000miles ago so I don't know, it's a cheap part anyway. I'm also considering replacing the water pump now. damn money pit.

It only takes one overheat to destroy a thermostat, as for the overflow tank, some fantastic, a sock on a stick and some elbow grease will make it good as new
This repair should not be expensive, do the pump, tstat, hoses, pressure cap and see what happens, worse case is you may need to add a radiator but then again you may not. I have not had good luck with rebuilt water pumps either, the price difference is $15 bucks between them and I go with new ones.
As for a flush, don't use any of those 15 minute wonder flushes, every time I have used one the water pump fails in a few weeks. I prefer the 7 hour prestone flush and the prestone backflush kit that goes on the heater hose.
If you decide to do your heater hoses use dealer OEM hoses, the have clamps already installed, the correct bends and sizes. On the main radiator hoses, use dealer supplied again, they come complete with the spring that keeps the lower hose open and the hose guards for the upper and lower hoses. When removing the heater hoses from the firewall do not just move the clamps back and pull the old hose off, slice it with a razor knife length wise and peel it off gently, you don't want to even break one of those bungs.

wow thanks for the detailed tip, it helps alot!

I've always used small gravel in the coolant tank to clean it. Just fill it about 1/4th with gravel and a little bit of white vinegar and gently shake it. The gravel will scrub the tank...just don't shake it too hard and break it. Then make sure to get all the gravel back out when you're done.

blackhawk411 said:

wow thanks for the detailed tip, it helps alot!

Click to expand...

One other tip, when you put the new hoses on and use the newer screw on type clamps, it's ok to use a screwdriver to start them and snug them up but use 1/4" ratchet with the correct socket to tighten them, a screwdriver does not get them tight enough.
Also when you remove the electric fan to get working room, that fans electrical connector has TWO locks on it so don't force it, look at it closely and you will figure it out, I fought with mine for 10 minutes before I figured it out, pushed the second lock and it about popped apart on it's own.
As for the water pump, don't try to cheat, you need to move that power steering pump bracket out of the way, if you reach down under the bracket you will find another bracket that goes back to the block and is held in place with a bolt, you need to remove it. Sop up all the water from around the water pump and the the hole it's in, it's a bad thing to get the new water pump gasket wet before you get it torqued down.
One other thing, you will see a pipe running up to the heater hose from the water pump, that has to come off and be put on the new pump or you can pick up a new one from the dealer OR 5-90 has a replacment for it with regular brass nipples.

Jess said:

I've always used small gravel in the coolant tank to clean it. Just fill it about 1/4th with gravel and a little bit of white vinegar and gently shake it. The gravel will scrub the tank...just don't shake it too hard and break it. Then make sure to get all the gravel back out when you're done.

Click to expand...

Now thats a good idea, the sock on a stick was tedious to say the least.