Davicl81

K, so last summer I replaced my radiator, h2o pump, t-stat and t-stat housing along with both radiator hoses and a new transmission coolant line. I noticed it had a lot of rust in it so I've flushed out a few times but the gunk keeps coming back. It's def. not coolant and oil mixing so I know my head gasket is good. Any other ideas of how to get it out for good? I'm super picky about keeping my baby well maintained so knowing this mud like substance is running through my engine drives me crazy. I've also tried the cooling system flush kits and cleaners a few times as well. Any ideas? It literally has the color and consistency of mud :-(... I also broke my oil cap while changing the oil yesterday. Any hints on getting it off before I get frustrated :-)

thecanman

I can't say much about the cooling system. I had the same problem with my oil cap. Just use some pliers to get your old one off and replace with a new one. I got mine at Advance Auto. It's one piece so it won't come apart in two pieces.

http://shop.advanceautoparts.com/web...RPCAPSAMS_____

Turbo X_J

Cooling system is too far gone to save. The only fix is to yank the motor, boil out the block & head in sodium hydroxide, then replace everything else with new. Probably not worth the expense, drive it till it dies.

ETA: Why did you replace those components was it just normal maintenance or did it overheat? If the later what is the oil pressure like?

RTorrez1

Just wondering, How long have you owned you jeep. It look like the po ran straight water or not enough coolant. If that is the case you will have to flush it several time to get most of the crud out. Make sure you flush the heater core separately. As far as the oil cap mine did the exact same thing. I still haven't replace it. I just use pliers to pull it when needed.

djb383

Looks like years of neglect to me. Antifreeze/coolant will not turn from green/yellow to rusty mud overnight....I call. LOL

Davicl81

It over heated on me and the old radiator cracked. I went ahead and replaced all of that at the same time. It was at that time that I noticed all the crud. I bought it used and never checked the fluids and condition.

No this was not an 'overnight problem' I just noticed it when I pulled all of that stuff out and replaced it. I ll prob jus give it a few more good flushes and leave it be. So far it's not causing problems but I know at some,point it probably will.

Davicl81

Oil pressure is great. No problems there

RTorrez1

It can be saved! Just keep flushing. I have a 65 Chevy pick up that was 10 time worst then what you have. Once you get it cleaned out keep an eye on it because you can get some crud even after you think it clean. Like I said clean the heater coil, radiator and the engine all separately.

djb383

That's the problem.....u can't leave it be. After it's flushed and filled with a good antifreeze/coolant/water mix, remove the rad cap (motor COLD) on a regular basis and check the coolant color and level. When coolant starts loosing it's color, it's also loosing it's anti-rust/corrosion ability.

BotakBeng

With all due respect, how did it even get to this in the first place.
Since you have replaced all of the cooling system except the heater core, i would suggest you look at that, as well as the heater hoses.

As a newbie DIY'er myself, i periodically keep an eye on parts that i replaced just to make sure i didn't screw up, so should you.

GL.

Radi

I've cleaned up cooling systems worse than that with CLR.
Two bottles, top up with water, run the motor a while with the cap off.
Drain, flush the heck out of it with water.
Refill with plain water, run the engine again and see what you have.
Sometimes I have to repeat the CLR 2-3 times...but it WILL get the rust and scale out of there.
Note that this is a last-ditch method to save a badly clogged system before pulling the block and tanking it...CLR does NOT play nice with aluminum. Don't leave any of it in there.

djb383

FWIW, at the CLR web site it says don't use in a automotive cooling system.

http://www.jelmar.com/faqclr.htm

Radi

Yes. And this bears repeating because if you leave any of the CLR in there, your radiator will become a watering can.
CLR will chew up aluminum if left in the system for any length of time.

The only aluminum in an XJ is the radiator, the block and head are cast iron.
Note I said 'last ditch before tanking the block', because that's what it is. But it does work.
If your radiator is already corroded and thin, CLR may finish it off. Even so, that is less costly than pulling the block and hot tanking it if that is your remaining option.

djb383

Gotcha......hope the OP understands.

NoClearCoat

I let CLR sit in my radiator overnight but I have a copper/brass/soldered rad. It wasn't overheating before but figured WTH while it's out..Plus a good block flush. Now it runs 10* cooler. New pump, t-stat, hoses, and tank because it sat for 6 years before I got it and I didn't want any trouble when I go out of town. Refilled with 50/50 mix of green coolant and DISTILLED water. Tap or well water will cause problems.. As mentioned, CLR loves aluminuim. Put some foil in a bowl of it and see what happens over 2 hours...