High Ambient Temperature

[Bob Culver]

I am surprised there is not more interest in thermostats . According to a wealth of literature it seems likley will make more difference to cyl and main bearing wear than any exotic oil or frequent changes of.

[Greig Smith]

Here is the link to page 147, clever mod, seems just a simple tube type thermostat held in place by a third hose clamp. Out here Mk1 Fiat Uno's used these tube thermostats

https://www.austinsevenfriends.co.uk/for...1&page=147

Aye
Greig

[Michael D]

as a matter of fact I AM interested in fitting a thermostat as indeed having one fitted should be beneficial to engine life....

Having looked up an inline-tube-thermostat.....I case one can live with the dreadful looks so close to the cilinder head (or else .... where can we put such a thing a bit out of sight...) on Amazon one can buy an inline tube thermostat
https://www.amazon.nl/Behr-Thermot-Troni...5817&psc=1


but this one although rather expensive looks less dreadful and methinks it can be painted matte black https://www.all4honda.com/nl/k-tuned-in-...98QAvD_BwE

for UK residents: http://www.force-racing.co.uk/products/b...t-housing/
costs 80 quid and uses a motorcycle thermostat.... less bulky....

[Michael D]

by the way.... what specification / opening temperature thermostat would you recommend?? In the past (TR2) I changed to a thermostat opening at 72 degrees centigrade instead of 75 degrees centigrade...

[Bob Culver]

Thrmostats should have soem sort of bypass even if just a generous hole. Otherwise can get very odd effects.

[Greig Smith]

Thrmostats should have soem sort of bypass even if just a generous hole. Otherwise can get very odd effects.

!00% agree with Bob, I had a thermostat fail once, cost me a cylinder head gasker on a 1300 twin cam Alfa. Since then I've drilled 4 or 5 holes in every one I fit. - 1/4" or 5mm holes are fine, no science here, just drill holes around the perimeter half way between the middle & the edge. Car takes a bit longer to warm up & once the thermostat opens it's academic anyway. Nowadays I run my cars on Evans Waterless Coolant which is like molasses when cold, so at least there's some movement of the stuff through the thermostat when cold, once at operating temps it's like water

Aye
Greig

[Chris KC]

Bob I suspect the reason there is not more interest in thermostats is that the existing system works fine and most people don't have issues with cylinder or bearing life!

I'm more worried about oil temperature (too low) than coolant temp (far less closely related than people imagine), but I must say it doesn't keep me awake at night.

[Michael D]

Bob I suspect the reason there is not more interest in thermostats is that the existing system works fine and most people don't have issues with cylinder or bearing life!

I'm more worried about oil temperature (too low) than coolant temp (far less closely related than people imagine), but I must say it doesn't keep me awake at night.

unless you're willing to spend a whole lotta time and work on fabricating a dry sump Austin 7 engine complete with all necessary ancillaries only to find there's no sufficient room under the bonnet at the right places, methinks there's not much one could do about that?? But aren't modern multigrade oils supposed to provide some half decent / sufficient lubrication at less than 80 degrees centigrade (please forgive I'm not familiar with Fahrenheits....)

[Bob Culver]

Hi KC
Many anguish over the ideal engine oil, resort to exotic stuff and consequently lay a very expesive exhaust trail, presumably in search of 200,000 mile rebores. But from what I have read cyl and ring wear effectively ceases with any oil above a reasonable cyl wall temp and this largely accounts for the increased life of 1950s and later cars and the amazing life of ultra fast warm up moderns. I suspect most would do better with Supermarket 15w/40 and a thermostat.

[Ian McGowan]

"I am using super unleaded petrol but was unaware that petrol can boil?

Chris"

Carburettor percolation occurs when the fuel in the carburettor float bowl boils
either during or after a hot soak condition. An engine experiences a hot soak
condition when the engine load is reduced or the engine is shutdown after a
period of operation at high engine load allowing the heat of the engine to soak
back into the fuel system. Engine and fuel system component temperatures
are elevated during the hot soak. During the carburettor percolation event,
fuel is forced into the inlet manifold through the carburettor vent or jet system,
this may give rise to an over rich mixture which can lead to poor hot restarting
or persistent engine stalling, (27).
Carburettor foaming occurs when the fuel rapidly boils as it enters a hot
carburettor generating foam. The foam cannot support the weight of the fuel
float, which sinks allowing more fuel into the carburettor promoting
malfunction of the engine as excess fuel is forced through the metering and
vent systems causing the engine to run excessively rich. The resulting
potential engine malfunctions are poor hot restarting, hesitation and stumbling
under acceleration of the engine, (27).