g13 coolant issues anyone?

[The_Hawk]

I sold mine a couple of years ago, but it got driven to QLD, VIC and all over NSW without issues. It always stayed right on 90 AC or not.

[Transporter]

interesting. starting to think that that G13 dont like VR6's lol.. as mentioned, def have noticed higher temps since using it. come weekend, im going to be dumping it, complete flush again and going back to valvoline zerex g05. I guess it is just suited more to the newer VW's. unfortunate as im all or the environmental factor, less emmissions, etc... but aint killin my ride over it...

What mixture ratio did you use? Did you bleed the system properly so there is no trapped air?

[gldgti]

Hang on - you changed the thermostat.

Nobody asked - is the new thermostat the same as the old one (temp range).

There is no reason at all that it would be the fault of the G13. You can prove it with mathematics and chemistry pretty easily that if you are running the same ratio of coolant/water, then no matter what the brand is, theres no way it will have an impact on cooling efficiency of more than a couple of percent. You just cant vary the heat capacity or its conductive properties by that much - coolant is basically just ethylene glycol, with some additives for corrosion reistance, etc.

More likely, either the new thermostat opens at a higher temperature than the old one, or the concentration of coolant/water has changed.

If you want the best cooling efficiency, you run more water - it has higher heat capacity than the ethylene glycol.

Its possible that if you have varied the concentration by a lot when you switched from old to new, this is the reason.

See below for more info:
http://www.engineeringtoolbox.com/et...col-d_146.html

Just to be clear on a couple of points:

Coolant takes more pumping effort than pure water
Coolant heat capacity is less than pure water

Therefore, if you change your coolant and end up with a ratio that is more concentrated ethylene glycol than before, then you can expect, (All other things begin equal) that the mean operating temperature might increase.

[fred27]

I'm using G13 coolant in my mk3 2E engine without issues. Second gldgti, only a thermostat with a higher opening temp would give you the result you are experiencing. I have used a higher ratio of coolant to water and only had a very slight temperature increase indicated on the temp gauge.

[Tubbs76]

Hang on - you changed the thermostat.

Nobody asked - is the new thermostat the same as the old one (temp range).

There is no reason at all that it would be the fault of the G13. You can prove it with mathematics and chemistry pretty easily that if you are running the same ratio of coolant/water, then no matter what the brand is, theres no way it will have an impact on cooling efficiency of more than a couple of percent. You just cant vary the heat capacity or its conductive properties by that much - coolant is basically just ethylene glycol, with some additives for corrosion reistance, etc.

More likely, either the new thermostat opens at a higher temperature than the old one, or the concentration of coolant/water has changed.

If you want the best cooling efficiency, you run more water - it has higher heat capacity than the ethylene glycol.

Its possible that if you have varied the concentration by a lot when you switched from old to new, this is the reason.

See below for more info:
Ethylene Glycol Heat-Transfer Fluid

Just to be clear on a couple of points:

Coolant takes more pumping effort than pure water
Coolant heat capacity is less than pure water

Therefore, if you change your coolant and end up with a ratio that is more concentrated ethylene glycol than before, then you can expect, (All other things begin equal) that the mean operating temperature might increase.

Hey mate, t stat is new and the same as old one. I played with the ratio on the seconf dump and made it a 40/60 ratio. made a slight diff but still pretty poor. ..ill dump again on weekend, re mix and give it another go. if no improvement, just gonna go back to using my original brand of coolant.. thanks for your help, much appreciated...

[gldgti]

Hey mate, t stat is new and the same as old one.

OK, so the other thing is that even if this case, they will not necessarily open at the same temperature.

I often will test a t-stat in a pot of boiling water on the stove - I have tested several 87's at a time and seen them open at different temps (old vs new) so this can also have an effect.

Just FYI

[Tubbs76]

OK, so the other thing is that even if this case, they will not necessarily open at the same temperature.

I often will test a t-stat in a pot of boiling water on the stove - I have tested several 87's at a time and seen them open at different temps (old vs new) so this can also have an effect.

Just FYI

Cheers for that, much appreciated. I dont think it is the issue though. seems to open same time, fan coming on same time. Im gonna drop it on weekend, flush out and re fill with the coolnt i was using. only way to determine. system has been bled and re bled, no leaks anywhere, new everyhting. The only thing i havemt changed is the expansion tank. Which Im gonna do anyway after xmas...

[Transporter]

Cheers for that, much appreciated. I dont think it is the issue though. seems to open same time, fan coming on same time. Im gonna drop it on weekend, flush out and re fill with the coolnt i was using. only way to determine. system has been bled and re bled, no leaks anywhere, new everyhting. The only thing i havemt changed is the expansion tank. Which Im gonna do anyway after xmas..

For the purpose of comparing the 2 coolants as you going to, you should use the same expansion bottle. Or just try a new expansion bottle with the coolant you have in now. You can also have a mechanical problem (cyl. head gasket, corrosion?)

[Tubbs76]

This is true. I just went and picked up a new bottle. I hope not the other (cylinder head, etc) but Im pretty confident it isnt. All started occuring once the swap of coolant took place. Could be the radiator however also unlikey as it is brand spanking new. Im also 150% confident has been bled correctly, etc.. when i do the swap, ill also pull radiator out again and flush Plus rest of cooling system. never had a problem with old expansion bottle either so why now?
just too coincidental all occured once g13 went in.

[h100vw]

This is true. I just went and picked up a new bottle. I hope not the other (cylinder head, etc) but Im pretty confident it isnt. All started occuring once the swap of coolant took place. Could be the radiator however also unlikey as it is brand spanking new. Im also 150% confident has been bled correctly, etc.. when i do the swap, ill also pull radiator out again and flush Plus rest of cooling system. never had a problem with old expansion bottle either so why now?
just too coincidental all occured once g13 went in.

If you replaced a heap of cooling system parts at the same time as the G13 went in, the G13 wouldn't be on the top of my list as #1 suspect.

Also, what's to say the temp sender isn't the problem?

Don't change too many variables in one, go if you want to work this out.

Whenever I mess with a cooling system, I always run tap water for the first couple of trips. I don't see it doing any long term harm. This is to verify there's no leaks and prevent wasting coolant. I know it cheap but it pains me to chuck stuff out for no reason.

Once I am happy its all good to go, I'll drop out the water and refill with the appropriate amount of coolant.

Gavin