Thermostat operating temp for GT6 Mk3

[Stewart Vacher]

Hi Guys,

In the recent warm weather I have experienced a couple of instances of over heating with my GT6 mark 3. Although each time it has occurred it has been in traffic jams, when the engine was on tick over.  I had an old Kenlow fan fitted on the front face of the radiator which did not have a thermostatic control but I could operate from a switch on the dashboard. Although functioning correctly it had little to no effect on reducing the temperature.

I decided it was only contributing to reducing the air flow through the radiator so decided to remove it. At the same time I removed the radiator to give it a good clean out. Unfortunately I found it to be damaged and have just ordered a replacement.

While I was flushing the system I thought I might as well renew the thermostat.  This is where my question comes in. Apparently there are three operating temperatures for GT6 thermostats, 74, 82 and 88 degrees. Can anyone please tell me which temperature was fitted as standard, and if there is any advantage in buying one with a different rating?

Many thanks 

Stewart

[johny]

First its possible an electric fan might reduce radiator airflow a little but this is only when going along. If youre getting hot in traffic but ok when driving then thats not the problem...

When you say it was overheating did it boil over or just show hot on the gauge? The latter is quite normal and if stable nothing to worry about👍

A new radiator will help keep the temperature down in traffic but of course theres still got to be sufficient airflow through it from the fan, mechanical or electrical.

Also when your engine is running hot any thermostat whatever its rating will be fully open so at that point it doesnt matter which it is...

[Pete Lewis]

if you look at the triumph spares manuals  yes there are 3 so in general ........

78 for hot climates

82 for uk /european climates

88c  for north america or cold climates

so for  UK its only the 82C  to use

88C in the uk would be after late emmision controls started to appear and leaner mixtures could be achieved 

eg spit 1500    but not GT6 's

 

and there are more supposed overheats down to guages.voltage stabilisers and senders than any main engine or coolant components      so dont assume    do some checking

if there are any charging or voltage variables you will get varying readings if the V stabiliser is playing up 

Pete

 

[Stewart Vacher]

Thanks Johny and Pete for your replies.

Yes the car has boiled over on a couple of occasions so hopefully the new radiator and good flush through will do the trick.

As far as the thermostat is concerned, following the information  you have given me Pete, I will be getting the 82 degree one and will look elsewhere should the over heating problem persists. 

Stewart

[johny]

Possibly the other current cooling thread on here might be of interest as well Stewart👍

[Pete Lewis]

have to say thermostats that have been "boilled"   seem to go out of calibration

overheating kills the wax plug best if cooked you replace it as a matter of course .

Pete

[dougbgt6]

Did you back flush the block with the garden hose?

Also these, they won't help you much in traffic, but dropped a half a devision on my gauge during normal running, crude but simple.

Lower the number plate, many of them block the tiny grill.

Stop the sag of the radiator cowl, a brace across the front or get a new aluminium one.

Doug

 

[Nigel Clark]

As stated already, 82C thermostat is best for the UK. 

You may this this old GT6 cooling thread of interest:

 

Nigel 

[Stewart Vacher]

Once again you guys have come up with various useful ideas.

Particular thanks to Nigel for pointing me to the previous thread on this subject, and Johny for the current one. 

Both the threads give me food for thought should the measures I'm taking not have the required result.

I already have a front cowl/duct and engine side valances and I think the numberplate is low enough not to block the grill.

I've flushed both the engine block and the heater with the garden hose.

I've ordered a new radiator and a replacement 82 degree thermostat (thanks for that info Pete). 

Here's hoping this combination will do the trick.

 

Stewart

 

[Ian Foster]

12 hours ago, Stewart Vacher said:

I've flushed both the engine block and the heater with the garden hose

Did you actually take the drain tap out as it is beneficial as you then have a larger hole.

It is also worth having a good poke around with a bit of stiff wire of a strong cable tie to try and dislodge any remaining crud.

Ian

[johny]

As an aside Ive always wondered if poor heat transfer from the engine due to muck in the water ways will actually shows as high coolant temperature. Surely if your gauge is showing hot the heat is getting into the coolant but not being dissipated fast enough by the rad? Course flushing is still a good thing to do👍