Do a coolant flush I've read. It's easy I've read (should've left well enough alone)

Noxid

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I've had a bottle Prestone coolant flush on the shelf for a while now that I bought to flush the cooling system of my Jeep. Figured it was a harmless project that is essentially a 30 min task tops, not counting driving to the beach and back a couple of times.

Monday I stopped being lazy and drained the radiator and filled it with the flush and because I was being extra nice to the Jeep I used distilled water to top it off. Drove to the beach stayed a while and drove home (30 min each way). Put it in the garage and thought nothing of it. Temps stayed normal and all was well. Rain and other obligations kept me from driving it Tues & Wed. Today I went to grab it again and saw a large puddle under the jeep. Uh oh!

I could still see water to the top of the radiator tubes when I took the cap off so I was thinking I just didn't snug the drain plug tight enough and a slow drip from a couple of days sitting looked more dramatic than it was. Then I removed my doubt by starting the jeep and try to see if my thought was correct. It wasn't.

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After I turned it off I had a steady stream falling out from under the water pump. Yay Me!!

So instead of taking the jeep to the drive on beach this weekend I'm putting a parts list together for all the "While Your In There's" for when I put a new water pump on. If only I left well enough alone until AFTER the long weekend.
 
Monday I stopped being lazy and drained the radiator and filled it with the flush and because I was being extra nice to the Jeep I used distilled water to top it off. Drove to the beach stayed a while and drove home (30 min each way). Put it in the garage and thought nothing of it. Temps stayed normal and all was well. Rain and other obligations kept me from driving it Tues & Wed. Today I went to grab it again and saw a large puddle under the jeep. Uh oh!

If only I left well enough alone until AFTER the long weekend.

Or, followed the directions. ;)

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Most of these products are to be used for a limited time period, but I think you're figuring that out.
 
Or, followed the directions. ;)

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Most of these products are to be used for a limited time period, but I think you're figuring that out.

My bottle had 2 options "quick clean" and "deep clean" instructions. I was following the deep clean that said to drive for 4 to 6 hours. I was going to drive it to and fro for several days to get to the 6 hour mark.

Lesson learned that it can't sit idle, I clearly missed that call out in the instructions and clearly relied too much on anecdotal stuff posted from others.
 
Or possibly flushed out the stop leak that was in there before.

Thermocure is the generally recommended flush around here. I believe you leave that one in your Jeep for a bit.

And now that you're going down the water pump rabbit hole you have decide if you're going for a stretch goal of a timing chain and crank pulley, and fan clutch, idler and tensioner pulley.

Have fun! =)

-Mac
 
Water pumps fail, that's what they do. I had the one on the old MBZ grenade on me about 3 years back. I heard a loud BANG!, didn't notice any problems so thought it was another vehicle.

Drove it a couple more days, until I was at a drive thru window and heard a strange sound from under the hood. Drove it home (wasn't far), popped the hood, and the fan was actually wobbling! Turned out the bearing had left the building and the impeller was being held in place by the seal! (!!!) Wasn't even leaking - damnedest thing I ever saw! Replaced it the next day.
 
I use Thermocure and Blue Devil flushes every 3 years. I leave them in for a total of 6-8 hours of driving. Never had any issues caused by the flush. Old water pumps go bad. I hope I didn't just jinx myself. Original radiator and water pump have lasted 23 years so far. :cautious:
 
I haven’t had any u-joints fail suddenly - they usually scream when going bad. Water pumps have always dribbled to let me know they were done. But that original radiator let go with no warning whatsoever.
 
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I'm more concerned about the original u-joints with a 241 tcase. Being poor isn't for pussies. Life is a gamble. 🤔

Better keep an eye/ear on that double cardan...it'll split a 241 wide open.

IIRC, mine started acting up at about 250K.
 
Ok, long weekend over with and back to reality. Y'all see anything obvious that I'm missing?

- Water Pump​
- Thermostat & Housing
- Upper & Lower Radiator Hoses
- Heater Hoses x2
- Serpentine Belt, Idler & Tensioner​

My cart right now $357 isn't as bad I thought it was going to be.

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Other than you're not getting a Robert Shaw thermostat it looks like a good list.

Do you have your original constant tension clamps?

-Mac
 
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