Which Coolant is Bad for the seals?
 

Yes I know another coolant question!

I found on one of the RX7 sites that a particular type of Coolant will attack the Water seals in the engine.

Can someone tell me which type it is (or ingredient it is) so I can make sure that I don't buy the wrong type.

Thanks..

supposedly the orange/red type but only about 2 guys had trouble with this type of coolant supposedly...

I had heard (incorrectly) in the past that Evans NPG+ was bad, but that just isnt the case. Could that be what you read?

i read on this forum that if you mix the green and orange coolants it can potentially be bad. but if you use just the dexcool (orange) or prestone (green) from the beginning and no mixing, then either should be fine.

what you may have read was about water wetter by redline. i heard that it slowly attacks teh O rings. i took it out since i never noticed a difference with it in. can this be verified about the WW so im not just preaching BS
kris

ive used watter wetter ever since 50k miles on the car. i got about 110k now on the original motor, so i guess its safe to say that water wetter is ok to use. :D

Yes, this is exactly what's bad. There's nothing wrong with running either red/orange or yellow/green, so long as you don't mix them. The iron oxide precipitates clog up the cooling system. Go ahead, ask me how I know LOL :) The reaction products from mixing also eat the aluminum in your cooling system. Once mixed, the precipitates, are extremely tough to purge. You need at least 7 gallons of distilled water to run through system to get rid of 99% of the reaction products. This is my experience. I have not read anything bad about Redline water wetter. Many race teams use 100% distilled water, and water wetter in the race motors with no ill effects.

Coolant above 255 Fahrenheit :withstupi

im going to call rick in the morning(monday) and ask him his take on water wetter. now that the system is at its best ever maybe i will notice a difference with water wetter. id like to drop my coolant temps while in traffic about five degrees. i have a koyo that does damn wonders, but only when im moving.
kris

I was told not to use water wetter, I forget the reason why...

try to find out why WW should be used. i heard the same thing and drained it the same moment i found out
kris

... also, as far as the two types go, switching is not gernerally a good idea - for the simple reason that you're going to mix some when you switch.

That said, I switched mine from green to orange (because I didn't know any better), flushed a month later (due to radiator end tanks cracking), and filled up with orange again. No problems since then. Granted, I only put 3K miles on in that 1.5 year span (from switch to sale).

moral: if you have green, stick with the green. ... and make sure you have the right water/coolant mix. ;)

Watter Wetter is bad? Dammit. I guess I gotta flush my coolant this spring. Dammit.

There's no definitive proof of this. From personal experience with 102,543 miles from the original motor, I'd say water wetter is fine, and offers very real benefits in lowering water temps, by decreasing water's surface tension, thereby increasing water's wetting capacity, and heat transfer capability. This is why the more water content you run in your coolant mixture, the better the redline water wetter works in your cooling system. FWIW, I'm running 85% distilled water, 15% Prestone Dexcool with one bottle of Redline Water Wetter in my KD Rotary street ported Malloy Mazda Reman (now 2000 miles old). Cooling sytem includes Koyo rad, Rx7 Store gloss black Pettit AST, and Power FC which kicks low fan speed at 86 C, high fan speed at 87 C. Peak water temps thus far with high 40s, low 50s ambient temps, and hard street driving is 87 C to 88 C.

I thought that water wetter was essentially a highly concentrated concoction of silicate - the "lube" in the green coolant. If I'm not mistaken, Dexcool (the orange stuff) is silicate free - which is part of its increased performance. Because of thise, I was under the impression that putting water wetter in Dexcool was defeating the purpose of using Dexcool. Not only that, but I thought that silicate in Dexcool would turn into something unfavorable for the water pump.

Am I completely off base? Anyone else heard anything about that?

ok... got a bit more info. Still haven't determined that water wetter is just a thick silicate, but it is designed to treat water (not coolant). You might mix a bit of coolant in to help the freezing/boiling point, but other than that, it only treats the water. The point is that coolant, while increasing the boiling point, stores a lot of the heat it absorbs. Water sheds the heat more quickly but will boil at a lower level. Water wetter helps the water not boil as quick and is able to shed the absorbed heat better than coolant.

Dexcool is silicate free. The green stuff is not. Silicate is supposed to be essential in the protection of Aluminum parts, but Dexcool has aluminum corrosion inhibitors. A high concentration of silicate can form a gel if it undergoes quick and large temperature changes - this gel can not only clog up the bits in your engine, but also form a thermal barrier over the surfaces that the coolant comes in contact with, drastically reducing the cooling effect of the coolant.

Dexcool allegedly performs better, but also seems to cause some corrosion problems in certain metals (brass being one of them - not sure if there's any brass in the FD system). This may be attributed the lack of silicate in dexcool or due to the type of water people mix with it.

On the water topic - it appears that distilled or purified drinking water are the best options for your coolant. Reason being is that dionized water has had minierals removed from it - the minerals were there to begin with because they were absorbed by the water in an attempt to come to a state of equillibrium with their surroundings. With no minerals present, the water is no where near an equillibrium state in your cooling system, so it will try to combine with all of the metals in the system in an attempt to be balanced. This multiple combining can lead to corrosion as one metal byproduct starts to mix with another.

moral of the story (reiterated): If your car came with Dexcool, stay with dexcool. If it came with the green stuff, stay with the green stuff. ... If you're going to use water wetter, make sure there's lots of water in the system or you're wasting your money. ;)

source: http://www.angelfire.com/ia2/vmax/coolantnotes.htm

more info on silicate -vs- non silicate: http://www.mr2.com/TEXT/HondaCoolant.html

dexcool, etc
 

Dave at KD thought he had a couple of problems with Dexcool, o-ring leaks and suspicious orange residue near leak point. Call him.

dexcool, etc ....

50/50 Dexcool will be more likely to leak thu tiny paths vs silicated antifreeze use ( 2 personal data points ).

water wetter has stuff that may not be good for dexcool. 'diesel' version of water wetter may be better choice with dexcool.

Dexcool may not be best choice for 300+hp rx's ... has to do with active surfaces like vibrating cylinder liners in diesels. I'd be concerned about severe cooling surfaces subject to nucleate boiling.

Zerex G05 is a hybrid long life silicated coolant, orange, and ok with reg water wetter.

Then, after careful thought and analization of this thread and ongoing problem, why doesn't everyone just spend the extra few dollars and get evans NGP+? It just sounds like the good way to go to me. It has a higher boiling point, can be run at 0 psi(less stresson sytem), doesn't corrode metal because it's waterless, and also lasts 5 times longer than normal coolant! Just spend the extra cash and time to flush the system out and put this stuff in! But there is a special way you have to flush the system before you put this stuff in, if anyone is interested say so and I'll post the instructions!

Re: dexcool, etc
 

I have 85% distilled water, one bottle of Redline Water Wetter, and 15% Prestone Orange (Dexcool-approved) in my KDR street ported Malloy Reman 13B REW. My motor has the silicone O-ring seals (included in Dave's "reliability mods"). It has only 2000 miles, so only time will tell...

I'm not sold on whether a higher boiling point allows the motor to run cooler. In fact, I've read from FD owners who've switched to waterless coolant, that their temp gauges read in the 220 F range all the time. You can interpret this one of two ways--the NPG has a very high heat transfer capacity, which is why the NPG reads 220 F all the time, or the motor's metal is really that hot! It's hard to know which is better, and only time will tell the tale. FWIW, if Evans were the way to go, the automotive industry would have picked up on this, and we'd all be running waterless coolant. Pro race teams would have been the first to run waterless coolant. Truth is no race team runs waterless coolant, because plain old distilled water has the highest heat transfer capacity of any liquid. Add Redline Water Wetter, wetting agent to decrease water's surface tension, thus increasing water's capacity to wet metal surfaces, and increase the heat transfer, and it's no wonder race teams stay with what works--plain old water :)

I've been turned on to using Mercedes coolant because it's been engineered to protect aluminum (Mercedes has been using aluminum engines since the beginning of time) It doesn't have any bells and whistles (promises of lower temps, miracle cures, blah blah) but I feel better using something that has been made specifically for Al. And if I remember correctly, there was an announcement about Mazda (I believe) changing their formula to be very similar to Mercedes, particularly for the new series of renesis motors..

For what it's worth..

The only things I'd like to add to this are:

1. I'm running NPG+ and a Fluidyne, and I have EXTREMELY low water temps. Even after 8 consecutive hard autox passes yesterday in 70 degree temps (not really that hot, I know), I never saw over 89C. Pretty amazing stuff.

2. Rob Golden swears by this stuff, and ships it with every motor he rebuilds (unless told otherwise). And, he said he uses it and has seen FDs running at 250F with little or NO power loss. That's pretty amazing. Don't know anything about race teams, but I trust Rob as a street and race guru.

-E

Most race teams run straight water because that's what the rules force them to use. In an accident or blowup, you don't want some exotic, hard to clean up, possibly very slipperly stuff all over the track.

Besides what is best for a street car is rarely what's best for a race car. Does a race team care about long-term corrosion effects or not freezing at -20F?

Wow! Not only do I get some great answers I also get a science lesson!

Thanks for the answers guys all very useful stuff.

The only problem is that being in the UK the brand names for the above products tend to be different.

But having said that you can get orange coolant and you can get green coolant (2 year change and 4 year change respectively).

Water Wetter is of course still the same name.