Colorado David
Explorer
Has anyone ever used Evans NPG+ in their Disco coolant? I asked a friend of mine, who happens to be an A&P mechanic, what he knew about Water Wetter and he suggested I try the Evans NPG+ instead.
Coolant question.
- Thread starter Colorado David
- Start date
UnfrozenCaveman
Explorer
Didn't Jim Hall run that in the VW diesel in his 88"?
Colorado David
Explorer
Here is what my A&P friend has to say about the Evans product;
JEFFSGTP
Observer
http://forum.miata.net/vb/showthread.php?t=17465
^^^above is a link to a review from what appears to be a decently knowledgeable tuner/gear head (reads not your typical ricer) having run it in his modded Miata...the car aside the characteristics he observed and described also make me hesitant to recommend using it in anything that would have the chance for temp spikes or heavy engine load for extended amounts of time aka...land rovers that can tend to run hot anyway, but in the end there is only one TRUE way to know for sure...buy it, try it, anotate findings, post findings for future reference...now whether you want to do that or not is of course up to you. I also think there would be different results for a petrol motor and a diesel motor.
^^^above is a link to a review from what appears to be a decently knowledgeable tuner/gear head (reads not your typical ricer) having run it in his modded Miata...the car aside the characteristics he observed and described also make me hesitant to recommend using it in anything that would have the chance for temp spikes or heavy engine load for extended amounts of time aka...land rovers that can tend to run hot anyway, but in the end there is only one TRUE way to know for sure...buy it, try it, anotate findings, post findings for future reference...now whether you want to do that or not is of course up to you. I also think there would be different results for a petrol motor and a diesel motor.
david despain
Adventurer
another A&P's take on it
I posted this over on DWEB but thought i would stick it here too
me on DWEB said:
I posted this over on DWEB but thought i would stick it here too
Mercedesrover
Explorer
I just switched to Evans coolant a couple of weeks ago in my Mercedes diesel 109. The research lab for Evans is in the town I work in and I know them very well. I talked to them at length before changing over.
Here is a bit of background and reasoning:
1) The truck is a '67 109 with an original 2.6L 5-row radiator. It was running a pretty constant 210 degrees in warm weather and would run about 230 climbing a long hill with standard 50/50 mix.
2) Yes, Evans coolant does not exchange heat as good as a standard 50/50 mix .
3) No, nothing exchanges heat better than pure water.
4) The trouble with a 50/50 mix is that even under pressure there are areas of very high heat around the combustion chamber and there are pockets of water rapidly boiling and condensing. This causes hot spots, warps heads, damages gaskets and everything else you can think of in regards to uneven temperatures in a casting.
5) The only reason engines can't run at temperatures higher than 210 or 220 is this spot boiling occurs to a large degree and uneven temperatures start to warp heads, etc. and cause the problems we all know about.
6) If you can keep the liquid you are using as a coolant from spot boiling and can keep the block and heads at a consistent temperature, you can run much higher temperatures without risk to the engine.
7) It is not a problem to run a cast iron engine with a cast iron head at temperatures of 250 degrees as long as you don't have areas of spot boiling.
8) Evans coolant boils at 375 degrees at zero pressure.
9) I changed to Evans coolant and at the same time changed out the questionable radiator with a new 3-core unit and changed the thermostat while I was at it.
10) Just got back from a 1200 mile trip in the heat.
11) The truck ran at 195 almost all the time. (I contribute that to the new radiator) On the very long and steep climb up Vermont Rt.11 the truck reached about 220 degrees and stayed there.
12) Even if the truck climbed up to 240-250 degrees I wouldn't have to worry as I know the engine is hot evenly and not being damaged.
13) Getting all the water out of your cooling system is a pain in the *****
Conclusions: Yes, your truck will probably run a little hotter with Evans but even so will be less likely to be damaged when you are running a very high temperature during periods of desert driving or environmental extremes that would overheat conventional coolant.
Here is a bit of background and reasoning:
1) The truck is a '67 109 with an original 2.6L 5-row radiator. It was running a pretty constant 210 degrees in warm weather and would run about 230 climbing a long hill with standard 50/50 mix.
2) Yes, Evans coolant does not exchange heat as good as a standard 50/50 mix .
3) No, nothing exchanges heat better than pure water.
4) The trouble with a 50/50 mix is that even under pressure there are areas of very high heat around the combustion chamber and there are pockets of water rapidly boiling and condensing. This causes hot spots, warps heads, damages gaskets and everything else you can think of in regards to uneven temperatures in a casting.
5) The only reason engines can't run at temperatures higher than 210 or 220 is this spot boiling occurs to a large degree and uneven temperatures start to warp heads, etc. and cause the problems we all know about.
6) If you can keep the liquid you are using as a coolant from spot boiling and can keep the block and heads at a consistent temperature, you can run much higher temperatures without risk to the engine.
7) It is not a problem to run a cast iron engine with a cast iron head at temperatures of 250 degrees as long as you don't have areas of spot boiling.
8) Evans coolant boils at 375 degrees at zero pressure.
9) I changed to Evans coolant and at the same time changed out the questionable radiator with a new 3-core unit and changed the thermostat while I was at it.
10) Just got back from a 1200 mile trip in the heat.
11) The truck ran at 195 almost all the time. (I contribute that to the new radiator) On the very long and steep climb up Vermont Rt.11 the truck reached about 220 degrees and stayed there.
12) Even if the truck climbed up to 240-250 degrees I wouldn't have to worry as I know the engine is hot evenly and not being damaged.
13) Getting all the water out of your cooling system is a pain in the *****
Conclusions: Yes, your truck will probably run a little hotter with Evans but even so will be less likely to be damaged when you are running a very high temperature during periods of desert driving or environmental extremes that would overheat conventional coolant.
david despain
Adventurer
the OP has an alum block and alum heads
Mercedesrover
Explorer
I can't talk with any degree of certainty about running aluminum engines at those temperatures. Both my Rovers run iron Mercedes diesels. I do know the biggest problem with those kind of temperatures are the rates of expansion between different metals so perhaps having both an aluminum block and heads negates that. Again, I can't be sure.
If the OP is serious about Evans coolant I can put him in touch with the people that have developed it.
Mercedesrover
Explorer
Thanks, Keith.
I like the idea of this stuff.
The trouble with with conventional 50/50 mix coolant is that it boils. That is the reason systems run a pressure cap....to increase the boiling point. When it boils you get hot spots and that's when you have trouble. If you can maintain an equal temperature throughout your engine, even if it's higher than you're used to seeing, you won't have any problems. We run this coolant in a pulling tractor that sees 260 degrees at times without trouble.
P.M. sent with contact information.
I like the idea of this stuff.
The trouble with with conventional 50/50 mix coolant is that it boils. That is the reason systems run a pressure cap....to increase the boiling point. When it boils you get hot spots and that's when you have trouble. If you can maintain an equal temperature throughout your engine, even if it's higher than you're used to seeing, you won't have any problems. We run this coolant in a pulling tractor that sees 260 degrees at times without trouble.
P.M. sent with contact information.
R_Lefebvre
Expedition Leader
Don't forget, the aluminum heads and aluminum block are being held together with steel bolts. The block and heads would be trying to expand faster than the bolts, which could end up stretching the bolts or ruining the threads. Either of which will result in loss of clamping force when the engine cools down.
Also, and probably the bigger problem for a Rover engine, is the steel cylinder liners. The aluminum block expands away from steel liner, allowing it to slip since it's held in with a press fit. Overheating these Rover engines usually results in slipped liners before warped heads.
Mercedesrover
Explorer
You'll get the same expansion differential with standard coolant. What this coolant does is keep small boiling points from occurring.
If there are areas inside your engine where boiling is occurring, (and there are) especially where a seal between steel and aluminum exists, this is where your problems will start. This location can spike a temperature far above what your coolant temperature is reading at the sending unit and you don't even know it. Evans coolant eliminates these spots of spiking temperature by remaining a liquid and continuing to take heat away where steam can't. Remember, Evans may not exchange heat as well as a 50/50 mix but it exchanges heat a hell of a lot better than steam!
Is there a chart that shows a comparison between the rate and degree of expansion between aluminum and iron as temperature increases?
If there are areas inside your engine where boiling is occurring, (and there are) especially where a seal between steel and aluminum exists, this is where your problems will start. This location can spike a temperature far above what your coolant temperature is reading at the sending unit and you don't even know it. Evans coolant eliminates these spots of spiking temperature by remaining a liquid and continuing to take heat away where steam can't. Remember, Evans may not exchange heat as well as a 50/50 mix but it exchanges heat a hell of a lot better than steam!
Is there a chart that shows a comparison between the rate and degree of expansion between aluminum and iron as temperature increases?
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R_Lefebvre
Expedition Leader
Aluminum expands linearly at twice the rate of steel. 0.6 in/in/F vs. 1.2. I don't know about iron, but I believe it's actually lower than steel?
I remember from my Heat Transfer classes, that boiling liquids actually transfer heat away much faster than if it stayed liquid. The latent heat of the phase transfer. But I may be misremembering that. I do know for sure, that quenching steel in water is faster than in oil, the water can remove the heat faster.
I remember from my Heat Transfer classes, that boiling liquids actually transfer heat away much faster than if it stayed liquid. The latent heat of the phase transfer. But I may be misremembering that. I do know for sure, that quenching steel in water is faster than in oil, the water can remove the heat faster.
Specific heat of water IIRC is 4.164 or something, its higher for water than for most other liquids due to the H bonding. Water has a higher Q than oil.
As for the latent energy, that is the energy between phase changes. As for removing energy faster, its an equillibrium, so a liquid will remove more energy if it is at a lower energy state. The removal of energy from the system doesnt happen at the liquid coolant level but at the radiator level.
-Sam
As for the latent energy, that is the energy between phase changes. As for removing energy faster, its an equillibrium, so a liquid will remove more energy if it is at a lower energy state. The removal of energy from the system doesnt happen at the liquid coolant level but at the radiator level.
-Sam