Thread: Coolant mix gives more power

Originally Posted by yt110

Would the difference in power have anything to do with the viscous fan?Don't they "lockup"when the engine runs hot,taking power from the engine?You say the engine runs cooler this may be whats happened.Someone who knows the workings of these fans might be able to add some more.

Good point actually.... The Viscous fan is designed to lock up at higher temp, therefore stealing HP.... on a big climb or towing heavy **** 5-8HP(rough guess) is a lot to loose.

Originally Posted by yt110

Would the difference in power have anything to do with the viscous fan?Don't they "lockup"when the engine runs hot,taking power from the engine?You say the engine runs cooler this may be whats happened.Someone who knows the workings of these fans might be able to add some more.

I have done mods to lower the "on" temp, factory Holden ones cut in at about 95C. Should be similar for any engine running an 88C thermostat I imagine.

If the engine is a TD5 then the ecu will cut back power if the difference between the ambient air temp and the inlet manifold air temp indicates insufficient inlet air cooling. This could be a cliff-face rather than a graduated reduction where just a few degrees higher inlet air temp would cause a significant reduction in power. The difference a large intercooler makes in a D2 is very significant on hot days because the power is not reduced even though the viscous fan might be locked, although the D2 has the extra boost mechanism provided by the boost modulator so there could be an even greater difference. This was observed with a D2a with standard ecu, before and after fitment of the large I/C.

Edit: Just re-read the 1st post and saw the 300TDI, so this is not applicable.

Originally Posted by rick130

Tim Slako (the Redline Importer) told me once that that is what they did to get around the overheating problem with GQ/Y61 TD42T Patrols, but I've never been game to try it, using OAT instead (and the thing still got hot.....)

Every cruiser I worked on over here got water wetter,every gearbox got MTL,the reconditioners would only honour the warranty on reco box's that were filled with it.Redline products are first class IMHO. Pat

Seems to me that the authors of earlier posts here presume corrosion inhibitor and anti freeze in coolant are the same thing.

Corrosion inhibitors are important, especially in motors with components containing aluminium in the cooling system. However, anti freeze is sometimes unnecessary and at times can cause problems.

Am not sure what if any anti freeze is used other than ethylene glycol. Problems with it is being expensive and not as good for transferring heat as water. Have also seen claims that it tends to coat surfaces with a film that is a poor conductor of heat. Seems best not to use it when not necessary. In Australian winters not much anti freeze is needed compared with that normally required in many other countries wher prevailing temperatures get far lower. Apparently coolant containing one third ethylene glycol will protect down to minus 18 degrees - colder than the lowest ever officially recorded temperature in every state except NSW. A truckie /earthmoving contractor in Victorian snow country once commented to me that you don't need much.

Have not had anti freeze in my 300TDI since changing the timing belt 3 years ago. So far no need, but have been giving it protection such as parking under cover if a bad frost is likely. Not even the first problem as experienced in the very dry and cold 1982 drought has occurred, ie motor getting hot because of frozen radiator.

Originally Posted by mox

Seems to me that the authors of earlier posts here presume corrosion inhibitor and anti freeze in coolant are the same thing.

Corrosion inhibitors are important, especially in motors with components containing aluminium in the cooling system. However, anti freeze is sometimes unnecessary and at times can cause problems.

Am not sure what if any anti freeze is used other than ethylene glycol. Problems with it is being expensive and not as good for transferring heat as water. Have also seen claims that it tends to coat surfaces with a film that is a poor conductor of heat. Seems best not to use it when not necessary. In Australian winters not much anti freeze is needed compared with that normally required in many other countries wher prevailing temperatures get far lower. Apparently coolant containing one third ethylene glycol will protect down to minus 18 degrees - colder than the lowest ever officially recorded temperature in every state except NSW. A truckie /earthmoving contractor in Victorian snow country once commented to me that you don't need much.

Have not had anti freeze in my 300TDI since changing the timing belt 3 years ago. So far no need, but have been giving it protection such as parking under cover if a bad frost is likely. Not even the first problem as experienced in the very dry and cold 1982 drought has occurred, ie motor getting hot because of frozen radiator.

Glycol is less efficient than water at conducting heat but the inhibitor package has a large bearing on this too.
Conventional silicate based coolants coat all the surfaces inside a cooling system to reduce/prevent corrosion further reducing heat transfer.
OAT and HOAT coolants only work where needed, ie they are reactive to any corrosion and deactivate it, so no blanket coating which is why their ability to absorb and transfer heat is better than a conventional inhibitor/glycol coolant

Originally Posted by mox

Seems to me that the authors of earlier posts here presume corrosion inhibitor and anti freeze in coolant are the same thing.

Corrosion inhibitors are important, especially in motors with components containing aluminium in the cooling system. However, anti freeze is sometimes unnecessary and at times can cause problems.

Am not sure what if any anti freeze is used other than ethylene glycol. Problems with it is being expensive and not as good for transferring heat as water. Have also seen claims that it tends to coat surfaces with a film that is a poor conductor of heat. Seems best not to use it when not necessary. In Australian winters not much anti freeze is needed compared with that normally required in many other countries wher prevailing temperatures get far lower. Apparently coolant containing one third ethylene glycol will protect down to minus 18 degrees - colder than the lowest ever officially recorded temperature in every state except NSW. A truckie /earthmoving contractor in Victorian snow country once commented to me that you don't need much.

Have not had anti freeze in my 300TDI since changing the timing belt 3 years ago. So far no need, but have been giving it protection such as parking under cover if a bad frost is likely. Not even the first problem as experienced in the very dry and cold 1982 drought has occurred, ie motor getting hot because of frozen radiator.

What about anti boil?

Originally Posted by Hardchina

What about anti boil?

That is why the cooling system is pressurised.