The gasket around the existing water pump or the water pump itself failed. I removed the draincock from the radiator (plugged with sludge/rust/muck), but the manual clearly states to remove coolant drain plugs from block. Given what I found at the base of the radiator drain, I'd really like to flush whatever I can. The 2004 DCA factory manual shows a drawing for a 4.7L V8:

2004 Dak shop manual

...except, on my 3.7L, either the plug was changed to an allen head plug or they covered it with the engine mount bracket:


In other vehicles in the past, I never bothered with the block plugs because I regularly changed the coolant and system showed very little corrosion. Also, I could easily drain the bottom radiator hose. Here, they attached these spring hose clamps, which are great, except they deliberately put in a stop to prevent full compression (insert expletive laden rant against engineers who should be keel-hauled). So, I can't expand the spring clamp enough to slide it up the hose or slide it down to free the hose. I should not need a Dremel tool to change the coolant.

Arrow points to @#!$!!&*!@! pin blocking clamp expansion.

If anyone can confirm the 3.7L drain plugs are the hex/allen head bolt or that they under the motor mount bracket, and/or provide an idea on how to remove the spring clamp without destroying it, I'd be very grateful. Alternatively, if you could give me the email of the rat who designed the spring clamp, I'd like to give him or her a piece of my mind.

Thanks,

 

On the spring clamp, a small set of vice grips will hold the clamp open. If it won't go over the swollen hose, pull the hose out from under the clamp. You may have to cut the hose, but that hose needs to be replaced anyway. The new hose won't have an issue with the clamp sliding on.

 

Looks like the 4.7L setup. You can pull the two bolts holding the black plastic part to the block and drain it that way and there would be no need to remove the hose. If the system is that mucky, you probably want to change the thermostat anyway. The plastic piece is the thermostat housing, so you should see it once you pull the housing off (i'm assuming it's like the 4.7L, sure looks like it). Just don't go ape on those bolts. I've heard of people snapping them.

Oh and I wouldn't mess with those block drains if they're not leaking. Besides, draining from the bottom hose will take care of everything.

 

Thanks for the suggestion.

Yes, I figure the hose needs to be replaced, but that will probably take several weeks. The truck (and I) are from the US, but we're currently in Poland. To get most parts I order from RockAuto and it can take 2-3 weeks for them to arrive. The engine was sold here in some later Jeep models, but I doubt the hose or radiator match. In any case, most things are less expensive online in the US.

Thanks again.

 

@Dodgevity Yes, the 3.7L is just a shortened 4.7L (2 cylinders lobbed off). Almost everything in the manual is identical for the engine, but sometimes they gloss over minor differences which are not covered even in the factory manual.

Back in Texas, I had a 2000 Dakota Quad Cab I bought new with the 4.7L V8. I loved that truck. I seriously regret selling it, but I really had no option as I had been overseas over a decade at that point. Anyway, it's amazing how much more room there is in the engine bay with those two cylinders gone...all the space is up forward between the radiator and front of the engine.

When I bought the new water pump, I ordered a thermostat too. I figured I should replace it since the engine did overheat. However, I was hoping to avoid it as I don't have a gasket for the housing.

I am trying to find it now with no luck, but I know I read somewhere with the right rubber seal, the water pump doesn't need sealant. I have appropriately rated sealant, I just don't want to mess with it if I can avoid it. Maybe it was in the thermostat section or on the RockAuto website in the extra info on the parts.

Anyway, I am going to take your advice. I decided earlier tonight, since I can't get the hose off anyway, I'll just take off the thermostat housing and replace the thermostat. Based on the sludge in the radiator, I really need to remove the thermostat and drain what I can from there. It's amazing the cooling system worked at all. I'll just use the sealant I bought.

​​​@Vimes suggested I replace the hose, and so I'll order those. I figure by the time they arrive, I can flush the system again and maybe more of the muck will have been dislodged to drain out.

Thanks much for the input from both of you.

 

I don't recall replacing a seal when I pulled off the thermostat housing. I believe I reused the seal as it was sort of like a large O-ring, if I remember correctly.

Edit: Actually, the gasket on the circumference of the thermostat itself, is the gasket that also seals the housing.

It is correct that you don't need sealant for the water pump. I skimmed the gasket with a light coating of RTV on each side, but yeah you don't need it.

 

Thanks much. It's been raining here all day, but I went out there and did a couple of things:
1) used dremel to cut off stop on spring clamp, and I was able to move it up onto the hose
2) took off thermostat housing...light rusty color, but no muck or sludge...so that was good.

I'll order the lower hose today. I need to order a replacement housing bolt too - it's marginal. The threads aren't crossed or stripped, just faint in one section. It was very hard getting it out. I should probably chase the threads on the block, or at least attempt to clean them. The upper thermostat housing bolt looks perfect.

That lower hose will take 2-3 weeks to get here. So, I'll put it back together as is, and see if it holds. Then I can order the right bolt from the US too. I'll look through the manual and see if it identifies the bolt anywhere.

Cheers,

 

Put some grease on the bolts before reusing. They don't need to be very tight.

 

Of course it wasn't specifically identified. My measurements with a caliper weren't much help as the corrosion through off some numbers and it easily could have been either an M6 or a 1/4. Well, I finally found it, MOPAR part number 6505502AA which is metric (I used 5/16" socket) M6-1.0 x32mm. I ordered replacement ones along with the hoses.

Thanks for the tip, I'll try the grease tactic. At the very least, it will make it easier to get them out when I replace them in a few weeks.
Cheers,