I have a question for those running the Evans NPG coolant. I am going to put in my new motor and I am considering running Evans as I hear it does a better job of cooling. I flushed the radiator out and flushed the heater core out as cood as possible without removing it from the car. Will it be abog deal if there was some residual coolant/water left in the heater core? I know it says not compatable with ater does this mean absolutly no water? I am sure there is still some left over water or coolant left in that damn heater core, it should be a very small amount left in there. Anyway any help or advice on this wouldbe great. I emailed Evans about it but got no reply yet. Also those of you running it is it really that much better than the 50/50 Antifreeze/ water mixture? Just wanna know if it is really worth the $150 to fill up my car on it.
Thanks
Jeremy

 

I have run it and will run it again. To remoce the residual water from your system, fill with 100% Sierra and run a while. You can also hook a cheap vacuum pump with a water trap up to purge the system.

To me it makes more sense to run Evans than to pour an electrolytic soltion into a system made of dissimiliar metals. ( Sounds like a recipee for disaster to em)

 

Thanks for the info I think I am gonna run it, I heard it does a better job of cooling. I have FMIC and a Alum radiator and Efan. Still I get higher than desirable temps I hope this will help with that a bit.

 

Evans naturally runs more hot than water for cooling, however it has much higher boiling temps and is supposed to lessen hot spots.

 

I don't know about it running hotter than water... Zkeller used it in his third gen and it never broke the 200 edegree mark when it dynoed 475HP at KDR....... Also... because it doesn't boil until like 350 degrees.. it builds no pressure in the system, i watched as he took the rad cap off when the car was at 195 degrees and.. nothing.. no coolant explosion, no steam..., just a cap comming off

They tell you to do all sorts of crap to your cooling system on the evans site.. the only mod Zkeller had to his cooling system was that the water holes through the rotor housings were enlarged a bit... Stock WP, hoses, Rad (third gen) and thermostat..

When I switch back to an E-Fan.. I'm going to run it.. I had to re-install the stock fan cause I was running a bit too hot for my liking with a Black Magic and my FMIC... (I'm no longer a fan of the black magic.. the fan's OK.. but the shroud just doesn't cover enough of the radiator, it leaves too much room

My next setup (after I get this damn third gen alt pulley fiaso settled) will be a Monster fan (3700 CFM) and shroud (they have all kinds of shrouds.. I think the late 60's camare is the best fit for a Koyo rad, have to re-check the dimensions.) from Vintage Air

 

It doesn't operate at zero pressure because of the high boiling point.
It operates at zero pressure because you are supposed to use a zero presure radiator cap with it. Evans will build pressure with heat as will any fluid in a sealed system.
Evans can run at zero pressure because of the it's ability to eliminate hotspots without any pressure due to the composition of the coolant itself. Water/coolant mixtures need to run at a high pressure to help eliminate those hot spots or the water would just 'float' over the surface that needs to be cooled.

Running at zero pressure is one of the biggest adavantages, especially with rotaries.

Downsides include lack of availabilty, price, not being able to top off the system whenever or wherever without carting some Evans around with you. Mixing Evans with water or anything else will ruin it. It also feels real nasty...like brake fluid, but will rinse with water as it is 100% biodegradable (a benefit )

I run it in my cars.

 

So this stuff does cool better than just 50/50 water and antifreeze correct..? Also I flushed my heater core out and there is probably still a small amount of water left. I probably wont have the motor in for another 2 weeks or so, do you guys think that water would evaporate in 2 weeks..?

 

those are some good points but the BIGGEST factor in cooling a wankel (which to my dismay gets overlooked far too frequently) is the oil cooler.

I mean why do you think mazda put an oil cooler on it from the factory that is larger than 99.9% of all other cars on the road? because it needs it - desperatley. Think about it this way, between oil and coolant, which of the two is the closest to the actual combustion going on in the motor? - the oil so therefore the hotter the oil, the hotter the engine.

My friend is running a pt-61 turbo with a v-mount setup, stock rad, e-fans (dual with a shroud) and a monster fluidyne oil cooler (4" tall x 24" wide x three rows) and it pulled 445 at the wheels and he has (to date) never had any trouble with overheating, it runs a rock solid 185-190 all damn day. This is the setup for me

 

id blow an air hose through the core just to make sure

 

I second that.

 

Ya thats what I am gonna do I think I finally got a reply back from Evans and here is what they said.
Jeremy...........I suggest using our NPG+, there is no water in our coolant
so it does not freeze. In extreme cold it will get somewhat thick, as it
does have the viscosity of a 10 wt. oil. The NPG+ is good to -40 and like I
said, it does not freeze and expand like a water based coolant.
Flushing the radiator and heater core with clean water is recommended
and blow out any residual water and let air dry if possible. We only want to
see a 3-5% water content left after changing over................Tom

 

Go to Harbor Freight, buy a $10 vacuum pump (evacuator) run on coolant system. VIOLA~ < 1%h2O

 

I don't recommend 0-psi radiator caps. Some of the pressure is to prevent vacuum from the water pump from collapsing the hose.

Even if you get all the water out, Banzai's recommendation to rinse with Sierra or other enviro-coolant will help reduce the water percentage everywhere else(hoses, cores, engine housings....).

If you are having cooling problems, fix them before converting to Evans.
It would be good to have all new cooling components(radiator/hoses/thermostat/heater core). It would suck to lose $150 of coolant to a 17 year old hose going to the throttle body or to a failed waterpump with 150k miles on it!

 

Thanks but I have new cool flex hoses, thermostat, aluminum radiator, caps, Efan and I still ran into times where the temp crept up past the point I would like it to. Anyway I just got a new rebuild so there is no coolant in the engine or radiator. The only place there may be any coolant is in the damn heater core. I will probably try the vacuum pump from harbor freight. Is ther anything I need to know when fluching the heater core...? Is there somthing that stops fluid from passing through it...? I just went out and tried to force some water though it again but not much really came out the other side. It mostly sprayed back on me.

 

I have used EVANS since 98 , best stuff ever invented for auto cooling system, I havent even hads my rad cap off in 2 yrs. 160 stat. vented, cruising at 175* steady,i do run a 7 lb. cap, I have a camaro big block i put it in back in 89, but it was the early formula to thick when cold would not flow ,slow warm ups. fine after that. any way the stuff was invented during the vietnam era, for helicopters, maybe befor e like WW2, the new formula seems to work better than anything I have ever used in a turbo rotary. RON

 

That's why some hoses either have springs in them or are thick walled.

I've been running it for years now at zero psi and road race with the car in my sig that uses Evans and have never had any problems with collapsing hoses restricting flow and increasing temps as a result. I run the stock hose btw.

Maybe you should recomend that directly to Evans so they can relay that info to everyone who has been running it in their high dollar race/show engines for years now under what Evans currently recommends...zero pressure.

 

buy one or 2 gallons of evans prep fluid...

This is what I did on my FD:

-emptied rad and core
-filled with 100% sierra and drove a few days with it
-drained and filled with sierra again and drove a few more days
-drained and filled with evans prep fluid and ran as per directions
-drained and filled with Evans NPG+

When I replaced my stock rad with a race aluminum one I reused the Evans, just drained it into a clean container and put it back through a coffee filter (just to be safe, it was perfectly clean) and topped up with fresh Evans as the rad was bigger than stock.

I agree that it looks and feels nasty

 

Ok thanks guys I appreciate all the input, I finally got my heater core flushed via garden hose. I forgot about the actuator, anyway I will pump the rest of it out via the vaccum pump from harbor freight. Now where do I find 7lb radiator caps..?

 

Good question.....