bad result from coolant change - how to fix?

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I had been using dexcool since the car was new (2000), never had a problem with it. Then I changed some of the hoses to silicon, and I got the idea from various internet postings that the eha(?) in dexcool could degrade the silicon, so I switched to Asian green coolant. Now about 5K miles later, I find the coolant is full of of crud, mostly chunks up to around 1/8", and even worse they're sort of sticky and won't easily wash off with water. How can I fix it?
When I changed the coolant, I first flushed with distilled water. I couldn't really get all the dexcool out, but I figured (mistakenly, I guess) that there wouldn't be a problem from what was left. I have only ever used distilled water for diluting the coolant.
Anyway, I guess I need to use some coolant flush chemical, which one is best? I would have to flush with a garden hose, then flush that out with distilled. Where I am the tap water is very hard and not suitable for mixing with coolant.
 
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You probably didn't get all the Dexcool out of the system and mixing them produces what you describe as crud. You have to flush everything out, you cannot mix the two coolants. I don't think you need a chemical to flush the system since it sounds like the crud is in suspension.
You had good results with the Dexcool since 2000 and why change from something that worked for you for so long? Personally, I never had a problem using Dexcool in my GM vehicles.
 
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Replace your silicone hoses or OE or gates....

I doubt that its a compatibility issue.

Replace the coolant with Asian green again.

Use RMI-25 now and with the new Asian coolant. You will probably have to repeat the fluid exchange again the future, and possibly again.
 
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Any radiator flush should do the job if you follow the directions on the bottle. Buy a few gallons of distilled water if your tap water is too hard.

Then, refill with Peak 10X
 
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How many hoses did you replace with silicone ones?
The problem is that we have few variables here:
1. Dexcool and the asian formula are incompatible.
2. Your silicone hoses are not compatible with the mix you created
3. A combination of the two above. That is the silicone hoses not compatible with one of the formulas and the formulas themselves not being compatible.

Personally I would get rid of silicone hoses as they are actually a downgrade to modern hoses, do a complete flush using an appropriate product, make sure the entire system is filled with just distilled water and then use whatever coolant you want.
 

neo4

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Yeah I'm definitely getting rid of the silicone hoses. The gunk that was created almost seems like it could be silicone. Just as a test I tried different cleaners on the radiator cap, nothing really worked.
As greasy suggested, I'll just stick with the Asian green though.
From research I did before I switched to it, seems unlikely this is a reaction between the dexcool and the Asian coolant.

I think the problem will be finding a detergent or chemical flush that works in this case. I don't think anything could be too badly clogged up though, since have had no overheating at all.
 
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