I run a bottle in mine here in 90+ humid as hell Florida. Flush my coolant twice a year with fresh 50/50 mix of distilled and the green stuff, then top of the radiator with a bottle of water wetter.

 

Well 8 months later and found brown sludge in my coolant reservoir. I hope it's not oil but it looks like the brown residue most ppl with redline experience.
Question, should I go with 50/50 mix or 25/75 split. I live in Florida where it seldom freezes and mostly autox this car. I did have a overheating experience this past weekend after consecutive runs.

 

If you don't have to worry about freezing temperatures, I'd just run straight water. It wouldn't hurt to put a little antifreeze in for insurance though.

 

water wetter works really good

 

Not good to run 100% water. Necessary lubricants for the water pump shaft seal are present in both antifreeze/coolant and Water Wetter. Both products also lower the surface tension of water which increases the resistance to nucleate boiling in the hot spots. And finally both contain anti-corrosion agents.

 

^ Truth

I also flush 2 times a year winter i'll run a 50/50 and late spring to mid fall a 25/75. I have never used water wetter in the EVO but used to run it religiously in my old Integra. Never saw any kind of sludge build up or anything.

 

Amsoil now has one off these miralcle coolant chemicals
I would let apagan chime in on it
I haven't rec'd mine yet to give a verdict

 

You are wasting money using the stuff on any car that has a functioning thermostat, radiator, and fan. I you add that stuff the logged temps will be the same because the ecu controls the temp window of operation. If your car is overheating then something real neads fixing

 

I used the proper mix ratio for water wetter in my R6..no build up of brown stuff. I saw a 4 deg. temp diff on a 100 deg. day between my bike and another r6. I should say his on straight antifreez water mix. It was in stop and go traffic during a slow ride.
Motul also has a coolant additive which I used in my evo with no strange buildup.

 

I've ran straight water in my car during drag racing season (usually March-Oct) for years now because a lot of the rule sheets require the use of water only. The last time I flushed my system I put water wetter in it, but I personally haven't noticed a difference.

I will start looking other options now though, especially during the winter season.

 

It seems to me the sludge would be caused by not letting the car cool down, and the redline sits in the turbo and bakes.

 

Not quite true. The surfaces inside the water passages can be hot enough to boil water even when the water temperature read by the thermostat is looking good. The rough surfaces also promote nucleate boiling. These little vapor bubbles that form have relatively poor thermal conductivity compared to water. The ability of Water Wetter and to some degree coolant/antifreeze to reduce the surface tension of water staves off nucleate boiling and reduces the ∆T between the cylinder/head surface and the water, so even while the thermostat will say that the coolant temperature is unchanged, the cylinder and head will be running cooler when running Water Wetter or antifreeze/coolant.

 

Mfred, so I could hear some bubbling when I stopped my car could that be due to me running a high concentration of water to coolant (30/70) and not doing a cool down lap? Either way I'm flushing my coolant out today brown build up stresses me out. This happened on my last car when I ran water wetter too.

 

You wouldn't be able to hear nucleate boiling. The bubbles are very small. If you hear boiling when the engine is shut off, that's full-on boiling.

 

Any thoughts on why I could hear bubbling when the car was shut down?