My water pump started leaking out of the pulley shaft and down on the balancer like that. Not nearly that bad though. I wouldn't drive that, it's on it's last leg and could leave you stranded anytime. When it starts leaking like that the coolant has gotten into the seals and bearings of the pump. It's done.

One thing I would do is clean it up really well and look around the timing chain cover to make sure it's not leaking there, but that looks like the pump.

 

My water pump started leaking out of the pulley shaft and down on the balancer like that. Not nearly that bad though. I wouldn't drive that, it's on it's last leg and could leave you stranded anytime. When it starts leaking like that the coolant has gotten into the seals and bearings of the pump. It's done. One thing I would do is clean it up really well and look around the timing chain cover to make sure it's not leaking there, but that looks like the pump.

How hard of a job would changing it be if I brought along a couple mechanically inclined buddies?

 

Took me a little more than an hour. The hardest part is scraping the old gasket off. Make sure it's not hot because when you remove a couple of those bolts coolant will pour out. I didn't remove the accessory bracket or any of the surrounding things. You wil probably want to replace your hoses too if they are old. Mine are new.

There are a lot of videos on Youtube on this.

 

When a water pump goers bad, it is designed to leak from the "weep hole" so that you can tell it is bad. Its an easy DIY replacement, especially with the youtube vids available. I would also do a t-stat, heater hoses, and radiator hoses if you can afford it. Its a good time to replace the serpentine belt as well, since you will have it off anyway :thumbsup:

 

went my pump went down the john, it wasn't really hard to replace. did the same as yours but when I pulled lightly on the pully, the coolant would just pour out like from a 2 litre bottle upended. took me a little over an hr doing it alone(Bolts were seized on pretty friggin tight to be using small wrenches >_<). I'd say the hardest part is scraping off the old gasket and getting the new one aligned properly, and using that stupid tensioner that the serpentine uses.. I hate that thing... I guess I got spoiled by tightening via alternator lol

 

I have to disagree about the tensioner, it makes things so much easier than loosening several bolts and having to pry like hell with a crowbar.

 

True, true. Though I would always use a tow strap and heave my body weight into it and that always worked good for the truck and car I used to have. Plus mine is a weird reverse threaded type. Have to "loosen" the bolt to tighten the belt. It's a few threads away from being off the "nut" base.

 

You can do a quick test on your thermostat...

If you suspect it may be bad, (and are working around there anyways) remove your t-stat and put it in some water and heat the water.
With a thermometer on hand, watch the temp, and when it reaches ~195* F , the t-stat should pop open. If it does not, it's defective and should be replaced.
It's not an expensive part (8-10$) so if replacement is needed, no biggy.

Good luck with water pump r&r!
JS

 

It could be either 4 things..

A. Water pump
B. Timing cover gasket
C. Water pump neck connection under the accessory bracket
D. Thermostat gasket is bad or the thermostat housing is corroded.

My hunch... is its the Timing cover gasket or Water pump neck hose. These Magnum engines seem to have a common issue with the timing cover gasket.. Mine leaked just like that and I had to replaced the gasket... Only way your going to know what it is is to start looking... Get a flashlight and look take off the a/c compressor and alternator disconnect the big coolant hose at the radiator side and drain the hose and bend it upward out of the way and remove the accessory bracket and find where the leak is starting from.. It will only take like 15 minutes to remove all that stuff if you have the tools.

The water pump if your like me and go slow and steady will probly take 2-3 hours assuming you have all the tools/parts and gasket... My suggestion if you do replace it is to use The right stuff RTV on it and not the paper gasket... I had mine leak using the paper gasket so I had to take it all apart again.. Now if its just the small 2 inch water neck hose... that will take like 30 minutes... If its the timing cover gasket.... that took me and a mechanic friend about 8 hours to do.

 

Not here I just put a ratchet on it with a pipe and pop the belt right off. Takes a few seconds.

 

The 4-slow has an adjustable tensioner, 5.2 has an auto tensioner. That's the one thing I don't miss about my XJ.

With the volume you're describing, I'm inclined to say it's the water pump. My timing cover gasket didn't drop that much coolant, and it had some pretty nasty spots.

 

I couldn't compare because I have not had the timing leak yet but I can say that my pulley was leaking a little but when I took the belt off and gave it a wiggle it started leaking a whole lot suddenly. I doubt I would have made it anywhere else with it.

 

You could be on to something there - I've never had a pump go with gusto, as it sounds like from what you're describing.

At the very least, the Magnum block makes it extremely hard to diagnose leaks. Everything is really close together, with a lot of stuff obscured.

 

Be careful when reattaching the thermostat housing, it's cast aluminum and likely soft with age. Torque to spec but be careful not to crack that housing.

 

Good point there.

Replace the steel inlet if you haven't done it in a while, or ever. It's probably warped and pitted.

$13 is what I paid at Napa if I remember correctly.

 

Take it from me, that thermostat housing is extremely easy to break.. Just did mine and the lower bolt hole sheared off when torqued down to shy of 20ft-lbs with a felpro gasket. That crap leaks like a sieve btw, just use rtv gasket silicone. 16ft lbs is recommended but wouldnt seal up at that, 20 snapped off the lower bolt hole. A washer has it held together till i get 3 hrs to take apart, replace the parts and let the rtv harden up. I have like 1/8" between the bolt head and belt right now XD

 

I just changed my O2 pump and Tstat, now i have a small coolant leak from behind the motor. 5.2L

 

It's most likely the rear end seal for your intake manifold. There are coolant passages near the rear 2 bolts.