High ambient air temperature

[mjheathcote]

Had fun late afternoon.
Attended a late afternoon /evening classic car show, but it was in a park in the centre of a local city.
The problem was it was very hot, and the traffic was bad.
Normally my Stag runs at around 90 degree C (mechanical temp gauge) but with the high ambient air temperature and no forward movement she crept up to 100.
Basically the mechanical fan couldn't cope (good coupling), well it did I guess, but the air temperature was so high.
She held her pressure okay and as soon as any decent forward movement the temperature dropped quickly, the problem I had was fuel vaporisation with the holley carb.
She stalled a few times but fortunately she also started okay, thank goodness for the new hi torque starter motor.
It is the first time in several decades I've had this problem, but it is also probably the first time it has been so hot too!
The queue getting in was also painfully slow and many owners getting frustrated just wanting to park up and let their cars cool down!

[Phil S]

you can always raise the idle speed a little (foot on the loud pedal) this spins the water pump a bit faster and can help cure this problem..an old solution but useful to remember.
Phil

[Hughesy]

I regularly run my car in 35 - 40 summer heat in Perth, Aus. You need to fit a decent electric fan. I don't run the mechanical viscous fan. I run an engine oil cooler and full synthetic oil for added protection. I also recently fitted a 12v "bilge" extraction fan which works in conjunction with the electric fan. This slows the under bonnet heat build up at traffic lights and speeds up the cooling once under way. See photo. I have fitted an electronic temperature sensor at the bonnet catch to monitor the under bonnet temps. I don't have any hot start issues.

Extract fan.jpgTemp Guage.jpg

[mjheathcote]

That looks like a good idea, I recall Renault fitted an electric cooling fan to blow onto the carb on their Renault 5 GT Turbo due to under bonnet temperatures and fuel vaporisation.
Regarding peak water temperatures when in traffic another option could be an adiabatic water spray system like they use on high performance cars to spray water mist onto the front of intercoolers,
I've also installed such systems in industry for additional cooling of air blast water radiators in hot summer conditions.
Of course, this summer may be just a one off for another few decades...