Jump to content

Diesel Engine Radiators: H20 Vs Coolant


Ahnsahn

Recommended Posts

Though my neighbor swears by it, is it a good practice, mechanically speaking, in this LOS climate to drive with only H20 in the radiator of a 2.5L diesel engine w/ A/C?

If it's practical, would that mean there is no need for a thermostat?

Would it be of any benefit to add a thermostat and engine coolant to this engine?

Link to comment
Share on other sites


Corrosion becomes an issue with any radiator after a while if you do not use coolant with the water. Also in a country like Thailand which is so hot only using water is a recipe for disaster, you lose that extra 15-20C of give you have because coolant has a higher boiling point as opposed to the water that can just flash to steam and cause no end of issues. For example warped head, blown head gasket, warped block and many many more fun and expensive things can be caused by serious overheating.

Link to comment
Share on other sites

Assuming this is for a road vehicle. If there is no thermostat then the velocity of the water through the cooling system can be to high and the correct heat transfer does not take place. This leads to the engine overheating. Lack of an additive to the water generally results in corrosion build up within the system which slows down the water flow. So starting from a new engine initially it would probably overheat and damage itself, followed by a brief period where the restriction caused by the corrosion slows the water down and all is equilibrium. Followed shortly by a blocked cooling system that continually overheats, damaging the engine. Is a lot simpler to have coolant (water plus inhibitor etc) plus a thermostat so the engine runs as designed. As a bonus when the engine is not running at the designed operating temperature it will probably consume extra fuel.

Cheers

Litlos

Link to comment
Share on other sites

Yes adding coolant in it's proper proportion would be of benefit as previously pointed out, personally I wouldn't bother with a thermostat but there purpose is to keep the engine at an optimum temperature.

In Thailand I wouldn't think a thermostat would be any benefit unless we start getting snow.:D

Edited by Kwasaki
Link to comment
Share on other sites

This has reminded me to check the thermostate because the cars cooling fan seems to come on very quickly not long after starting off, it hasn't got a temperature guage, I would be more concerned about overheating in Thailand.

Edited by Kwasaki
Link to comment
Share on other sites

Your neighbor is somewhat correct.

Pure water has a much better thermal heat capacity than coolant and is less viscous or flows better. Meaning it will remove and transfer heat better than 100% coolant.

But water is never pure. It has all these minerals and stuff that will clog and rust your insides.

Coolant is needed to decrease the freezing temperature of the water and increase the bioling temperature.

Coolant also has these rust inhibitors and lubricants, etc.

There is a reaon why most manufacturers recommend a 50/50 mix and coolant at the dealer is already pre mixed.

One needs the best of both.

Personally I would use 100% water than 100% coolant because the coolant is too thick to flow correctly and doesn't remove heat enough so it lowers the capacity of the radiator.

Link to comment
Share on other sites

'' Anti-freeze'' contains stuff to stop corrosion of alloy parts and do a job. You MUST have. Thermostat keeps everything at the right temperature for the manufacturers specification. Some differ in temperature setting so the correct temp stat must be replaced with the same temp opening window. The stat will have a temp window stamped on it. :)

Link to comment
Share on other sites

Your neighbor is somewhat correct.

Pure water has a much better thermal heat capacity than coolant and is less viscous or flows better. Meaning it will remove and transfer heat better than 100% coolant.

But water is never pure. It has all these minerals and stuff that will clog and rust your insides.

Coolant is needed to decrease the freezing temperature of the water and increase the bioling temperature.

Coolant also has these rust inhibitors and lubricants, etc.

There is a reaon why most manufacturers recommend a 50/50 mix and coolant at the dealer is already pre mixed.

One needs the best of both.

Personally I would use 100% water than 100% coolant because the coolant is too thick to flow correctly and doesn't remove heat enough so it lowers the capacity of the radiator.

Rubbish. :rolleyes:

Link to comment
Share on other sites

Your neighbor is somewhat correct.

Pure water has a much better thermal heat capacity than coolant and is less viscous or flows better. Meaning it will remove and transfer heat better than 100% coolant.

But water is never pure. It has all these minerals and stuff that will clog and rust your insides.

Coolant is needed to decrease the freezing temperature of the water and increase the bioling temperature.

Coolant also has these rust inhibitors and lubricants, etc.

There is a reaon why most manufacturers recommend a 50/50 mix and coolant at the dealer is already pre mixed.

One needs the best of both.

Personally I would use 100% water than 100% coolant because the coolant is too thick to flow correctly and doesn't remove heat enough so it lowers the capacity of the radiator.

Rubbish. :rolleyes:

+1

Its kind of obivous that using 100% coolant (as in non diluted concerntrated coolant)is at best a completely retarded idea, its not designed to be used on its own its designed to be mixed.

Higher boling point = Better for engine, therefore Coolant(as in properly mixed coolant)>Water alone

Link to comment
Share on other sites

Hey guys, I love to hear all the technical facts and opinions from those in-the-know about mechanical subjects, I always learn something! Thermostat, temperature and corrosion are the key words that make the case for me.

Thanx!!

Link to comment
Share on other sites

Hmm ,

It is difficult .

Corrosion , yes certainly cooling liquid ( ethyleneglycol ) has major advances . It prevent rust forming while water does not ( and even hot water does more , hot water is very corrosive ) .

On the boiling point i tend to disagree .Water is a massive heat transporter and close to the very best around . As far as i know , but i am not 100% sure it is better then EG or PG ( ethylene glycol or propyleneglycol ) . When water boils it draws out enormous amount of energy , while producing steam . That is a +1 on the water side since EG or PG will not boil at those temp .

I guess a mixture of both is the best , you do not need the same amount of EG in Thailand as you do in the western world , as long as the temp is not near freezing level . Even a bit of EG is enough to have the corrosion resistance and protect the rubber things ( gaskets engish name ?? ) while the water is THE better coolant .

Link to comment
Share on other sites

Vehicle manufacturers are always looking to save money per vehicle. If just plain water in the cooling system was better or even just OK and the thermostat were not necessary, I can assure you they would use plain water and add no thermostat.

Many years ago when engines were mostly made of cast iron and coolants were not as good as the coolants today, the system, including the radiator would partially clog so thermostats were removed and the engine ran a little cooler. When that no longer worked, they would use VERY caustic chemicals to flush the clogs out of the system. Using those same chemicals today would eat your engine.

Link to comment
Share on other sites

Hey guys, I love to hear all the technical facts and opinions from those in-the-know about mechanical subjects, I always learn something! Thermostat, temperature and corrosion are the key words that make the case for me.

Thanx!!

I have rebuilt V8 engines where no or not enough anti corrosion stuff (anti-freeze) was used to see the cast iron corrosion showing inside the cylinder walls, piston side. :o. Take the freeze plugs out of the sides of a cast iron block and look inside, you would be amazed at some l have seen, and getting it all out is another story. :)

Link to comment
Share on other sites

Your neighbor is somewhat correct.

Pure water has a much better thermal heat capacity than coolant and is less viscous or flows better. Meaning it will remove and transfer heat better than 100% coolant.

But water is never pure. It has all these minerals and stuff that will clog and rust your insides.

Coolant is needed to decrease the freezing temperature of the water and increase the bioling temperature.

Coolant also has these rust inhibitors and lubricants, etc.

There is a reaon why most manufacturers recommend a 50/50 mix and coolant at the dealer is already pre mixed.

One needs the best of both.

Personally I would use 100% water than 100% coolant because the coolant is too thick to flow correctly and doesn't remove heat enough so it lowers the capacity of the radiator.

Rubbish. :rolleyes:

+1

Its kind of obivous that using 100% coolant (as in non diluted concerntrated coolant)is at best a completely retarded idea, its not designed to be used on its own its designed to be mixed.

Higher boling point = Better for engine, therefore Coolant(as in properly mixed coolant)>Water alone

Correct!

Link to comment
Share on other sites

Hmm ,

It is difficult .

Corrosion , yes certainly cooling liquid ( ethyleneglycol ) has major advances . It prevent rust forming while water does not ( and even hot water does more , hot water is very corrosive ) .

On the boiling point i tend to disagree .Water is a massive heat transporter and close to the very best around . As far as i know , but i am not 100% sure it is better then EG or PG ( ethylene glycol or propyleneglycol ) . When water boils it draws out enormous amount of energy , while producing steam . That is a +1 on the water side since EG or PG will not boil at those temp .

I guess a mixture of both is the best , you do not need the same amount of EG in Thailand as you do in the western world , as long as the temp is not near freezing level . Even a bit of EG is enough to have the corrosion resistance and protect the rubber things ( gaskets engish name ?? ) while the water is THE better coolant .

Again correct +1!

Link to comment
Share on other sites

'' Anti-freeze'' contains stuff to stop corrosion of alloy parts and do a job. You MUST have. Thermostat keeps everything at the right temperature for the manufacturers specification. Some differ in temperature setting so the correct temp stat must be replaced with the same temp opening window. The stat will have a temp window stamped on it. :)

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Link to comment
Share on other sites

'' Anti-freeze'' contains stuff to stop corrosion of alloy parts and do a job. You MUST have. Thermostat keeps everything at the right temperature for the manufacturers specification. Some differ in temperature setting so the correct temp stat must be replaced with the same temp opening window. The stat will have a temp window stamped on it. :)

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Was the air conditioner on? If so that could cause the fan to start before the engine is hot.

Cheers

Litlos

Link to comment
Share on other sites

'' Anti-freeze'' contains stuff to stop corrosion of alloy parts and do a job. You MUST have. Thermostat keeps everything at the right temperature for the manufacturers specification. Some differ in temperature setting so the correct temp stat must be replaced with the same temp opening window. The stat will have a temp window stamped on it. :)

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Was the air conditioner on? If so that could cause the fan to start before the engine is hot.

Cheers

Litlos

No Idea :D..Have you looked under that plastic head cover. Silly Show idea. I Love those jelly moulds, they don't keep tumbling over. Another six months and im Tractor Free at last.

Link to comment
Share on other sites

'' Anti-freeze'' contains stuff to stop corrosion of alloy parts and do a job. You MUST have. Thermostat keeps everything at the right temperature for the manufacturers specification. Some differ in temperature setting so the correct temp stat must be replaced with the same temp opening window. The stat will have a temp window stamped on it. :)

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Was the air conditioner on? If so that could cause the fan to start before the engine is hot.

Cheers

Litlos

No Idea :D..Have you looked under that plastic head cover. Silly Show idea. I Love those jelly moulds, they don't keep tumbling over. Another six months and im Tractor Free at last.

I didn't know you had a Harley Davidson :whistling:

Link to comment
Share on other sites

Though my neighbor swears by it

No more listening to that neighbor when it comes to motor vehicles!

...Ha-ha-ha, you got a point there! If something sounds feasible enough, I like to bring it here for you guys to help sort out.

Link to comment
Share on other sites

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Thermostat's at the bottom of the engine block, where the lower radiator hose goes.

As for the main discussion, running plain water, while it can give you 100% best heat transfer is dumb, even with distilled water, as corrosion is A Very Bad Thing. Some mentioned using a 50/50 mix of coolant and distilled water, that is fine. Most cars have more cooling capacity than they really need, it's not like your engine will explode if your heat transfer capacity is only 95% compared to pure water!

But keep in mind some of the coolant you may buy is already pre-mixed (i.e. OEM Toyota coolant), makes things a lil easier. And, if needed, you can top-up with distilled water, available at any service station or supermarket for what, 10B a bottle?

Link to comment
Share on other sites

Started the engine up today Early morning 7:00am for me, after 3 mins the cooling fan was kicking in, feeling the top hose and the bottom hose, it was obvious something was wrong with the thermostat, but on the Yaris ( jelly mound) to you, where the hell is the thermostat housing. :blink:

Thermostat's at the bottom of the engine block, where the lower radiator hose goes.

As for the main discussion, running plain water, while it can give you 100% best heat transfer is dumb, even with distilled water, as corrosion is A Very Bad Thing. Some mentioned using a 50/50 mix of coolant and distilled water, that is fine. Most cars have more cooling capacity than they really need, it's not like your engine will explode if your heat transfer capacity is only 95% compared to pure water!

But keep in mind some of the coolant you may buy is already pre-mixed (i.e. OEM Toyota coolant), makes things a lil easier. And, if needed, you can top-up with distilled water, available at any service station or supermarket for what, 10B a bottle?

Yep, the coolant manufacturer will tell you on the ''can'' what ratio to use. :)

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.








×
×
  • Create New...
""