Hey guys - I recently replaced my radiator with a 3-core, brass/copper. Put a Tefba filter in the upper radiator hose and an inline filter in the heater hose going to the heater core.
Got 246k on this baby and want to keep the engine/radiator. etc. "gunk" free as much as possible.
I used to have a Prestone inline tap to backflush the system but that thing eventually cracked and I lost that heater hose - plastic won't last over the years so took that out (I was lucky - I had a spare hose IN THE BACK and was able to get back on the road right away and not overheat, etc.)
Questions (looking for recommendations):
1. How often should I flush the coolant system?
2. What is the best chemical flush that I can use that will get rid of the layer of rust inside the water jackets that might be limiting the heat transfer from the engine to the coolant? (note: hopefully, whatever chemical additive someone recommends will also dissolve that rust in the block good enough that it won't cause other problems and will dissolve the rust enough that it won't clog up my new radiator!)
3. Finally, is there a better fan? I don't mean fan clutch, but the metal fan itself that I could replace that will actually pull more air just because of how it might be aerodynamically designed?

Thanks for your help everyone and a shout out to cruiser54 for all the advice he has given me over the years to keep my RENIX going strong.

 

Evapo-Rust. They have a product called Thermocure which is specifically designed for the engine cooling system but the original Evapo-Rust formula works fine as well.

 

If I was ever to try one I would try the EvapoRust stuff myself.
I really like their rust remover so....
Maintenance is key IMO.
I swap out my anti-freeze every other year.
I use the 100% green stuff with distilled water.
This is what it looks like in there when you do just that.
About 4 years ago when I had to do a water pump.

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That looks real good.

 

Must just be here that enough Evaporust to flush a cooling system would probably cost more than a new rad.

Years ago, some old school mechanic recommended "Harpic" which, if anything, was too effective but not seen it for a very long time & no idea what it's modern equivalent is here, never mind a corresponding American product - but it was a toilet cleaner in powder form, probably more for clearing pipes than shining bowls.

 

blueridgemark had something in his signature that worked well. Lemme see if I can find it.

 

IIRC, is was powdered detergent from Amway.

 

Yes!! Use Tide instead? That's what we've used to clean our shop floors for years.

 

I have used the generic Prestone flush in the past and had great results with it.

 

Probably the simplest solution.

 

But without a recommendation it's just snake oil, which is why the cheap domestic products will always find favour.

 

Post 9 is a recommendation.

 

That it is. Based on using it on at least 5 different very neglected XJs at that.

 

There ya go.. Using facts and experience to try and convince people.......I love that!

 

1... every 2 or 3 years if using the "5 year" prestone green antifreeze on an iron engine, every 2 years on aluminum is what I do.
2... I use the Prestone flush when needed. follow its instructions it should not be needed if system is maintained correctly
3... the Grand Cherokee fan clutch is supposed to provide better cooling as it engages sooner or disengages later so I am told. I run it. An electric fan is added to the left of the engine driven fan. make sure both work correctly. a bad fan clutch can cause engine driven fan not to work correctly. so test your fan clutch plenty of test method videos are on the youtube.

good luck