Damage after no thermostat?

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Owlsman
Minor Fan
Posts: 325
Joined: Fri Nov 30, 2018 6:26 pm
Location: Sheffield
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Damage after no thermostat?

Post by Owlsman »

Greetings. A few weeks ago, with your help, I managed to sort out the volatile readings on my 'professionally' fitted temperature gauge.

It seems I needed to have the feed via a voltage stabilizer which my '62 Minor didn't have on the speedo - so with someone's recommendation here I fitted a stand alone electronic semiconductor V S and all seemed fine except that I could not get the car up to a reasonable working temperature.

Of particular concern was, when going down a longish decent i.e. when engine not working hard, the temperature that I had generated all but disappeared! Long story short and all that.....I removed the thermostat cover to find that THERE WAS NO THERMOSTAT fitted. I have now fitted an 88 degree jobbie, been for a run just now and what a surprise, the gauge goes up to 90 (well JUST below, of course), and stays there - up hill and down dale.

I read some historic threads last night which did seem to give conflicting opinions about the dangers of running without a thermostat. I only bought the car last Sept and apart from the odd tootle into Derbyshire it's hardly been driven. I don't think it got much use prior to my ownership but of course I've no idea how long it's been running without a thermostat and why! It was a bit of a struggle to get the thermostat cover off as 2 of the 3 studs were 'encrusted' on the cover, suggesting that it has been like that for a while.

What damage could the absence of a thermostat have done and can I do any simple tests to check anything?

The car does seem to be running OK but I have noticed that since it has actually got up to a proper working temperature, for the first time since I've had it, the oil pressure is a bit lower than it was. Not surprising, I suppose as the oil will be hotter and thinner than it's been for yonks. There's plenty in, by the way. Accelerating hardish uphill, in top gear, it's showing 55ish but drops to 50 or just below tootling along on the flat and drops again to 30/35ish on tick-over. A bit low methinks...….but I'm no expert on such matters.

Any pointers or (hopefully) reassurance you can give me would, as always, be much appreciated.

Alan
philthehill
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Re: Damage after no thermostat?

Post by philthehill »

If your engine is running as it should be you will not have created any damage by running the engine without a thermostat.

I have run Minor engines without thermostats and have experienced nil damage.

The thermostat helps push coolant to the rear of the cylinder head so keeping the head cool especially around the exhaust valve seats.

Only if the engine is pushed very hard with no water circulating around the rear of the head would you experience any problems.

When the engine temp rises the oil will get thinner. Your tick over /idling oil pressure is well within spec which should be 15lb or more.

I would suggest that you do not worry about the engine or oil pressure and enjoy the car.

Phil

pgp001
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Location: West Yorkshire
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Re: Damage after no thermostat?

Post by pgp001 »

You will probably find your heater works a lot better as well :D

Phil
oliver90owner
Minor Legend
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Re: Damage after no thermostat?

Post by oliver90owner »

Not forgetting better fuel economy in these winter months!
Owlsman
Minor Fan
Posts: 325
Joined: Fri Nov 30, 2018 6:26 pm
Location: Sheffield
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Re: Damage after no thermostat?

Post by Owlsman »

Thanks for reassurance guys.

Yes, on my little run today I noticed that the heater actually worked! :D

I know there are arguments for and against about fitting additional instruments (more to go wrong, more to worry about, early warnings of trouble etc. etc) but I have to say that without fitting the temperature gauge it would never have occurred to me to check that there was a thermostat fitted.

Thanks again.

Alan
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