29-04-2021, 09:55 AM
I fitted the thermostat in February 2015. Since then we have covered 10,540 miles with no problems whatsoever. The car boiled only twice. Once climbing a notorious hill in The Dales on one of Malcolm Parker's runs and once in Perth on the way to Blair Atholl for the SA7C's AGM in November 2017. We were in a traffic jam for 20mins with no fan belt. I remove it in the winter.
I had to replace the thermostat recently because the original one failed.
The car has a motormeter so we can see what's going on. The engine warms up quickly then maintains a steady temperature. I drilled two 1/8" holes through the flange to allow bypass and make sure they are placed vertically to avoid air-locks. However with no water pump there should be virtually no pressure across the thermostat unless the engine boils so normally bypass is not needed.
The flow rate of thermo-syphon is probably very low so the thermostat should make no difference.
We have only had fuel vapourisation once. It was on the way to Malcolm's Masham to Kelso run. We climbed to the top of one of the highest roads in England in very hot weather and stopped to admire the view. The car was reluctant to restart and the carburetor was boiling merrily. It did start and ran very rough for a few minutes. It is an updraught Zenith.
I can't see how a thermostat could affect vapourisation.
I had to replace the thermostat recently because the original one failed.
The car has a motormeter so we can see what's going on. The engine warms up quickly then maintains a steady temperature. I drilled two 1/8" holes through the flange to allow bypass and make sure they are placed vertically to avoid air-locks. However with no water pump there should be virtually no pressure across the thermostat unless the engine boils so normally bypass is not needed.
The flow rate of thermo-syphon is probably very low so the thermostat should make no difference.
We have only had fuel vapourisation once. It was on the way to Malcolm's Masham to Kelso run. We climbed to the top of one of the highest roads in England in very hot weather and stopped to admire the view. The car was reluctant to restart and the carburetor was boiling merrily. It did start and ran very rough for a few minutes. It is an updraught Zenith.
I can't see how a thermostat could affect vapourisation.
Jim