g13 coolant issues anyone?

[Tubbs76]

Recently did a flush and thought I'd try g13. Have been running a week odd and must say the result has been very disappointing to say the least. Coolant temp on average is higher, can't run my air con with coolant teno soaring too 100c and have also noticed my oil temp is now averaging 100c as opposed to 94-96c. Has anyone else has any issues with this coolant? I'm ready to dump and go back to my old brand...

[Umai Naa!!]

What about other things like pressure cap, thermostat, and radiator condition? Have you tested the fans?

100deg Celcius for coolant temp isn't boiling when it's pressurised.

Bare in mind, the weather has been getting pretty hot these last few days.

[mb1907953]

You're doing well with an average oil temp of 94-96... I sit at 100-105 up here in brissy.

[Tubbs76]

Whole cooling system is virtually brand new. New t stat, t stat housing, flanges, crack pipe in last 6 months. All new silicone hoses in last 3 months and a new aluminum radiatorca week ago. Expansuon tank and cap also new. Has been bleed properly etc..has only started running high since the g13 put in. Even when driving, coolant temp pretty much on average between 88c -90c. Normally only hits 90c if sitting in traffic. Otherwise normally 80c -82c when driving consistently. I've never had my coolant temp hit 100c with air con on even in a hot day. Oil temp also noticeably higher. Fans all work properly and cone on at 90c.me thinks me going back to valvoline zerex g05. As it stands, out performs g13 by a mile. I was speaking with kay offline and he also mentioned he was using a castrol coolant and swapped to g13 recently and he also noticed higher temps and he is also going back to his normal coolant of choice..maybe g13 and vr6 don't mix?

[Tubbs76]

Yeah. Even on a hot day driving on motorway, I haven't hit past 104c. Now I'm sitting on a 100c just putting around...

[Tubbs76]

Has anyone else had any similar experiences with G13?

[mb1907953]

Has anyone else had any similar experiences with G13?

I run g13 but admittedly get the higher oil temps you're talking about. Although I sit at about 90C with coolant temp.

[Tubbs76]

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...

[The_Hawk]

The VR6's run pretty damn warm, even with the G12/G12+ I was running over 100c on oil most of the time and well above that if you pushed it hard. I seriously considered getting an oil cooler, but then it was really only an issue when it was on the track

Even though oil would go up I never saw the coolant needle go anywhere but straight up, pointing at 90. Other than the fact it built up to that point while warming up I'd almost say it didn't work! It was always completely stable.

[Tubbs76]

The VR6's run pretty damn warm, even with the G12/G12+ I was running over 100c on oil most of the time and well above that if you pushed it hard. I seriously considered getting an oil cooler, but then it was really only an issue when it was on the track

Even though oil would go up I never saw the coolant needle go anywhere but straight up, pointing at 90. Other than the fact it built up to that point while warming up I'd almost say it didn't work! It was always completely stable.

How do you find it with the air con on? when air con on, coolant tem siting at 100c. that crazy.. does yours do the same or does it saty at 90c

[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/ethylene-glycol-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...