OAT coolant

Grumpy

Getting old is not for wimps
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I have just received my Evans liquid and flush and hope to do the coolant change soon. Do I leave the reservior bottle or remove it, and if so how do you bypass the tubeing? I don't do high rev riding, I just need something to do in the low mileage season.;)
 
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MattR

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North Hampshire UK
Why do you want to use this stuff? Is it because the s10 suffers from over heating. If so, what is the cause of the over heating? What are the advantages of running at a higher temp with this stuff? Won’t the thermostat still attempt to keep the temp at normal ?


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Grumpy

Getting old is not for wimps
Joined
May 28, 2013
Messages
411
Location
Surbiton U.K.
Why do you want to use this stuff? Is it because the s10 suffers from over heating. If so, what is the cause of the over heating? What are the advantages of running at a higher temp with this stuff? Won’t the thermostat still attempt to keep the temp at normal ?


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No mechanical reason, no more than I changed the turn indicators for LED's, fitted a gear indicater etc. I just find something to do. And as the coolant has a long life, it may be one thing less to do in the future (Yes, I have just contridicted myself;))
 
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WJBertrand

Ventura Highway
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Jun 20, 2015
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Ventura, CA
I have just received my Evans liquid and flush and hope to do the coolant change soon. Do I leave the reservior bottle or remove it, and if so how do you bypass the tubeing? I don't do high rev riding, I just need something to do in the low mileage season.;)
Almost all matter expands when heated, even miraculous Evans coolant, so yes, unless you want coolant dumping out the overflow hose onto the road in front of your rear tire, keep the overflow bottle! As I understand it the only change would be to use a lower pressure cap. The engine should run at the same temperature as before because the thermostat and fan will work to accomplish that.

Both devices will be worked harder though as the specific heat capacity (not to be confused with temperature) of Evans coolant is less than the traditional 50/50 water and ethylene glycol based coolants. What that means is that the volume of coolant in the engine will reach it's heat capacity sooner in the case of the Evans and need to be released into the radiator where it'll dump it's smaller load of heat more frequently. So the thermostat will cycle more and the fan will run more often.

Most OEM cooling systems have enough reserve capacity to handle the less efficient cooling medium, which is why you can get away with using this product. If you thought your cooling system was marginal, even when in perfect mechanical condition (recall 50-60s era British cars), then using this coolant might not be such a great idea.

I've had cars and bikes go well over 100,000 miles and in a couple of cases 200,000 miles with no cooling system related problems. Changing the coolant occasionally hardly qualifies as burdensome maintenance. The whole idea seems to be a solution to a non-existent problem, IMHO.
 
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Sierra1

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And, I've "heard" that they only recommend changing to Evans when you completely tear down the engine, and reassemble it. They "say" that Evans does not play well with water, and that if you don't get all the water out when transitioning...."bad things" can happen. I won't know because I'm a boring OE kinda guy.
 

jrusell

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Aug 23, 2017
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Dartmouth, Nova Scotia, Canada
I have just received my Evans liquid and flush and hope to do the coolant change soon. Do I leave the reservior bottle or remove it, and if so how do you bypass the tubeing? I don't do high rev riding, I just need something to do in the low mileage season.;)
You do not get rid of overflow bottle.
When your engine heats up the coolant is going to expand and a small amount will be released into the overflow bottle. When the engine and coolant cools down it will then be sucked back into the rad and kept at a proper full level.

If you remove the bottle it will spit that small amount out the overflow when the engine is hot and it will be lost. Next time the engine cools it will draw a slight amount of air onto the system. Over time you will continue to lose more and have more air in the rad.

Keep it as it is.

Personally I think you are trying to find an issue that does not exist. Normal coolant is fine for 5-6 years. It takes maybe 15-20min to do a coolant swap. Keep normal coolant and change every few years. You said you were looking for work to do in the off season didn't you?

Let's say you are on a trip and you have a small coolant leak. Maybe something simple like a hose clamp came loose or the cap on the overflow reservoir came off and you now need to top up the rad. What are you going to do? Water and Evans are not comparable so you need to drain whatever is remaining, flush the system completely and switch back to normal coolant.

For a vehicle you are going to take on the road far from home I see this as making the bike less not more reliable.
 
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ballisticexchris

Guest
I have just received my Evans liquid and flush and hope to do the coolant change soon. Do I leave the reservior bottle or remove it, and if so how do you bypass the tubeing? I don't do high rev riding, I just need something to do in the low mileage season.;)
Just run a single tube off the top of the radiator and zip tie it pointed down. Don't be too concerned with the skeptics. Almost everyone who bags on Evans has not actually used it. It is a fantastic low maintenance coolant that works just as advertised. And it does not corrode over time. I have been using it in both my KTM300 and Beta 498 for many seasons. I'm not all that good of a rider so it just made sense for those super long slow sections where I was lifting, pushing, and bulldogging my bikes over the nasty trails.


Almost all matter expands when heated, even miraculous Evans coolant, so yes, unless you want coolant dumping out the overflow hose onto the road in front of your rear tire, keep the overflow bottle!
You do not get rid of overflow bottle.
When your engine heats up the coolant is going to expand and a small amount will be released into the overflow bottle. When the engine and coolant cools down it will then be sucked back into the rad and kept at a proper full level. Water and Evans are not comparable so you need to drain whatever is remaining, flush the system completely and switch back to normal coolant.

Evans does not build pressure like regular coolant. It does expand but not much at all. You can even pop off the cap at over 250 degrees and not get sprayed. If you fill the radiator to the very top of neck then it will spit out only a very small amount. From then on the level stays the same and an overflow bottle is not needed. Evans and water are perfectly compatible to each other. However the advantages of Evans are lost and you are just running with basic coolant which does build pressure.

Here is my coolant level after over 6 years of running the same batch of Evans. Lots of runs at well over 300 degrees and it remains just over the top of the fins. I don't have an overflow bottle and I have never added a drop. I initially filled it up to the top of the neck. After just one hot ride it burped out a small amount and it stays at the same level. I have had my bike at over 320 degrees with the gas boiling and so hot I lost the clutch lever. It still does not expand enough to pop the cap spring and lose coolant.

8FD62227-49CC-4E12-926B-12F0A2411840.jpeg
 

MattR

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I don’t understand this at all. But then I’ve just got this useless jelly stuff where my brain should be..


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Cycledude

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Rib lake wi
Just run a single tube off the top of the radiator and zip tie it pointed down. Don't be too concerned with the skeptics. Almost everyone who bags on Evans has not actually used it. It is a fantastic low maintenance coolant that works just as advertised. And it does not corrode over time. I have been using it in both my KTM300 and Beta 498 for many seasons. I'm not all that good of a rider so it just made sense for those super long slow sections where I was lifting, pushing, and bulldogging my bikes over the nasty trails.







Evans does not build pressure like regular coolant. It does expand but not much at all. You can even pop off the cap at over 250 degrees and not get sprayed. If you fill the radiator to the very top of neck then it will spit out only a very small amount. From then on the level stays the same and an overflow bottle is not needed. Evans and water are perfectly compatible to each other. However the advantages of Evans are lost and you are just running with basic coolant which does build pressure.

Here is my coolant level after over 6 years of running the same batch of Evans. Lots of runs at well over 300 degrees and it remains just over the top of the fins. I don't have an overflow bottle and I have never added a drop. I initially filled it up to the top of the neck. After just one hot ride it burped out a small amount and it stays at the same level. I have had my bike at over 320 degrees with the gas boiling and so hot I lost the clutch lever. It still does not expand enough to pop the cap spring and lose coolant.

View attachment 61844
how did the inside of your radiator fill get so dirty looking ? I’ve never seen one looking so dirty before.
 

WJBertrand

Ventura Highway
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If you fill the radiator to the very top of neck then it will spit out only a very small amount. From then on the level stays the same and an overflow bottle is not needed.
This is probably mostly true, though it will spit out a bit more each time you reach a higher temperature than before. The radiator will eventually be running with a measure of air space above the coolant level. Given the limited heat capacity of the coolant, I would want the system as full as possible, and the elimination of air in the system provided by the overflow tank would further inhibit the possibility of corrosion. Keep the overflow tank, oh and the fan too.
 
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ballisticexchris

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how did the inside of your radiator fill get so dirty looking ? I’ve never seen one looking so dirty before.
It's the natural color of the coolant as it comes out of the bottle. It does get slightly darker over time. But nothing to be concerned about.

This is probably true, though it will spit out a bit more each time you reach a higher temperature than before. The radiator will eventually be running with a measure of air space above the coolant level. Given the limited heat capacity of the coolant, I would want the system as full as possible, and the elimination of air in the system provided by the overflow tank would further inhibit the possibility of corrosion. Keep the overflow tank, oh and the fan too.
That is for sure a good reason to keep the overflow tank. The coolant will always stay at the very top. OTOH it's just not enough reason for me to have one. As far as the fan I would get rid of it on the Super Tenere is I was to do any kind of extreme riding (anything that would cause the fan to jam into the radiator in a fall). Evans does not corrode over time. Since it's waterless there is nothing to contribute to corrosion.
 

jbrown

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Novato, CA
Maybe it been too long since my college thermodynamics and fluid dynamics courses, but I'm pretty sure you still need to have air flowing past the radiator to remove the heat. No matter what coolant you run. And you need to keep the motor at a reasonable temperature (I'd shoot for the designed temperature, myself). Slow running certainly heats up my Tenere until the fan cools it down. I wouldn't remove the fan unless I knew there would *always* be plenty of air flow past the radiator.
 

s.ga.rider

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Dec 23, 2019
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South Georgia
I changed my coolant a few weeks ago. So much easier than my previous fjr. I used yamacool so no worries with compatability and its fairly cheap.
 

Shifter44

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Mar 13, 2020
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Ohio
One of the advantages of using a waterless coolant like Evans, is that you can use it unpressurized which is probably better overall to prolong the life of seals and hoses I use it in my 1996 Yukon and I just removed the inner seal on the radiator cap so it flows freely to the overflow reservoir. I plan to do the same for my S10.
 
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