Since we have no way to compare the Zerex cleaner with the Motorcraft cleaner, I don't think any of us can say it is safe. Personally, I would use NO cleaner before I would use a questionable cleaner.

 

I have flushed my system 5 times and it still looks like this. Do I need to be worried?

 

If your coolant is dark and oily like the picture above, then yes, you have a problem!!!

Coolant should be free of all contaminants (old or new). First, did you have a problem that was previously corrected and the radiator fluid not changed, cleaned and flushed... or you have a new problem of oil and blow-by getting into your cooling system (EGR cooler, warped heads... or something serious).

Good luck,

 

If it's not clearing up, you probably need to step back and use the Motorcraft cleaner, then go through all the distilled water flushes again. I flushed it 5 times, and the drained water never looked completely crystal clear, but it was getting close. Also, I did NOT use any cleaner.

The oil floating on mine was residue in the bucket. It's not much oil at all, and the camera highlighted the difference in color.

I thought mine looked pretty bad. Those of you who have flushed yours, how did your first drain compare to mine?

 

Because of the oil and the cost of the VC-9, I would do a Simple Green flush 1st and then the VC-9. If the Simple Green doesn't clear the oil I personally think that you would be wasting the 55 bucks for the VC-9 since its primary purpose is an iron cleaner.

 

There is no oil in coolant flush. Let the last bucket set out over night and it looks the same like brown rusty water. Will remove T-stat and try simple green.

 

It doesn't take much brown color looking down in a bucket to make it look dark.

If you flushed 5 times, you still have about 3% of the original coolant mix.

1 = 50%
2 = 25%
3 = 12%
4 = 6%
5 = 3%

And that's best case, assuming you got a good mix after each flush, which is doubtful.

I don't think simple green is going to do anything for the rust. It's a good oil cutter, but the iron cleaner will do a better job of cleaning up the rust. But more clear water flushes will further reduce the % of original rusty water too.

If you fill a clear quart jar with the water you just drained out, I'll bet you will discover it is clearer than you think.

 

the brown color is rust. its caused by a PH balance issue. Im not a chemist so I cant really tell you the best cure other then to flush it drive it and flush it drive till its clean then flush it with distilled water and vc9.
have you drained the block on both sides yet? that may help you speed the process.

 

No, I have not.

 

And I thought you were doing these flushes with the t-stat out. Flushes quicker that way. I thought you pm'd me on the procedure but apparently you are not following it. Correct me if I'm wrong. And if the brown is not oil then definetly go to the VC-9.

 

Who are you speaking to?

The flush procedure that I wrote up and has been posted many times does not indicate to take the t-stat out. I personally, do not want to mess with it and I just drive my truck several miles in between each flush (with heater on) and with distilled water and after the 5th time, that is all I have left... 100% distilled water.

Drop it one more time, add 3.5 - 3.7 gallons of coolant (3.7 since I have a coolant filter) and all is well.

Now... if you have a lot of sediment or oily residue, then you need to use Simple Green and the VC-9 cleaners. I would use tap water to flush the heck out of it as it is cheaper than distilled water. Maybe open the pet-**** up and let the hose run into the degas bottle while your truck is running and the heater is on. Eventually, the key is to get all the "gunk" out, Simple Green out and the VC-9 cleaner.

Then... do my flush procedure with the distilled water to get the tap water out... and your hopefully back to a perfect 50/50 mix of distilled water and coolant.

Good luck,

 

He was only speaking to me.