Fan clutch or coolant flush first?

[macleanflood]

If you're going to do a flush pull the radiator and do the fan clutch...it'll make that job easier...and make flushing the block easier. And you wouldn't be the first person to wing a radiator and knock a hole in one while sneaking in a fan clutch. And those fins are brutal on knuckles.

If it's bad, bad you can pull the water pump and thermostat housing for more access and some deep cleaning.

-Mac

 

[TheBoogieman]

History is spotty, I picked it up last October with ~32k on the clock after it was mostly parked during the PO’s divorce. I did the typical fluid changes when I got it last year + replaced the rad cap with a new stant after the coolant was changed. Attached is what the coolant looked like before it was changed last year. Everything I’ve worked on has been original, so I’m assuming the water pump is as well.

Thermocure is in order for this weekend.

View attachment 365026

That's not coolant, that's a pumpkin spice latte smoothie.

 

[TheBoogieman]

Definitely drain the block. Its a little bit of a hassle, but worth it.

Why?

 

[cpwolf]

That's not coolant, that's a pumpkin spice latte smoothie.

I’m embarrassed for you, that you can name one of those. If you said that’s an October Wheat IPA would have been cooler, HA

 

[rubicube]

took mine to the shop an had them look at the ac,,,told them it's not as cold.they came out and said change ur fan clutch ur ac will be colder,,,,,
DUH,told them my rubi isn't overheating.they said it will someday, so I changed it an walla the ac is colder an temp is exact 210.

 

[red02tj]

What I drained out…I can see crud/rust between the fins. So far I’m getting better temps with just Thermocure and water.

 

[cpwolf]

What I drained out…I can see crud/rust between the fins. So far I’m getting better temps with just Thermocure and water.

View attachment 365322

View attachment 365323

The Thermocure most definitely will be black, and stink big time.

 

[red02tj]

How it started and how it’s going. Should I expect it any clearer?

 

[JKP]

Wow! In theory, if you put in clear water, that's what would come back out, but you may not be able to achieve that.

 

[cpwolf]

How it started and how it’s going. Should I expect it any clearer?
View attachment 366011

On the right is good, how many flushes to get there?

I'd put in the thermostat the way it should, a Mopar etc with the bleed hole drilled into it. A touch of grease on the lip will help it hold in place and get the clean surface or new cover that goes over it. Then fill with 50/50 HOAT like Zerex 5 and Distilled water.

Let it run and look for the thermostat opening up etc. I usually run it on my driveway that has a slight incline, and when it goes down, add a touch more until it steadies, then put the radiator cap on. Fill the overflow and done.

 

[red02tj]

I ended up with two bottles of Themocure so I put one in on Saturday, run for about an hour ish, then drained and flushed with the hose on Sunday it was pitch black. What’s coming out now is from the second bottle and and ~3hrs of runtime since Sunday. I think I’m on flush 4, not including the time I just let the hose run down the radiator. I’ve been using old 5gal water cooler jugs…way easier than milk containers.

 

[cpwolf]

I ended up with two bottles of Themocure so I put one in on Saturday, run for about an hour ish, then drained and flushed with the hose on Sunday it was pitch black. What’s coming out now is from the second bottle and and ~3hrs of runtime since Sunday. I think I’m on flush 4, not including the time I just let the hose run down the radiator. I’ve been using old 5gal water cooler jugs…way easier than milk containers.

Here in the Austin, Texas area, so much calcium and other minerals, I don't wash mine with anything but distilled. It's a pain to a degree, but I just try to keep anything out. But it looks good you should be good to go.

 

[red02tj]

Here in the Austin, Texas area, so much calcium and other minerals, I don't wash mine with anything but distilled. It's a pain to a degree, but I just try to keep anything out. But it looks good you should be good to go.

the first two times I ran the hose the help get some of the extra crud out, the rest have been distilled

 

[red02tj]

After refilling and a 30min drive + Idling for 15 with the AC, temps now max at 220 which is down from ~236 but still higher then it should be..Il check coolant level in the radiator after it cools down, any other suggestions.

 

[diggerwolf]

Why?

You want to get all that Prestone, Thermocure, and nasty old rusty antifreeze water out of the block for a proper flush.

I did. Removing the drain plug is remarkably easy when you have the correct tool.

CTA Tools 2036 8mm Hex Drain Plug... https://www.amazon.com/dp/B00FRLBF4M/?tag=wranglerorg-20

 

[RMETeeJay]

Pressure test. Should hold at 16PSI for 20-30 minutes. While you wait, go around with a good light and look for leaks.

 

[red02tj]

Pressure test. Should hold at 16PSI for 20-30 minutes. While you wait, go around with a good light and look for leaks.

I put in a new stant radiator cap last year, whats the likelihood it went bad? I’ll rent a pressure tester tomorrow.

 

[RMETeeJay]

I put in a new stant radiator cap last year, whats the likelihood it went bad? I’ll rent a pressure tester tomorrow.

Slim to Nil, but if I had the tool I would test both.

 

[red02tj]

Pressure test. Should hold at 16PSI for 20-30 minutes. While you wait, go around with a good light and look for leaks.

Help pressure for 20+ min between 15-16psi and no leaks I could see.

New Thermostat is next I think.

 

[Mud Mixer]

I replaced the water pump in my 97 4.0. The rear bearing was going bad and finally leaked coolant. It would always run hot (210+) with the a/c on regardless of operating conditions in the S. Fl summers. The new Gates pump and HD fan clutch scrubbed at least 20 degrees. A little play in the shaft must have a huge impact on coolant flow. Water pumps are cheap.