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#781635 17/07/23 12:55 PM
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The thermostat on my Morgan has decided to remain closed frown No wonder it was running hot!
I have found a replacement on Rimmers site but I have a choice of 3.
One is identified as Aftermarket for £3.78, another is OEM at £18 and a third Genuine Landrover at £22.34
Rutters have one for £16.44
Needless to say they all look the same although I am reluctant to get the cheap aftermarket one.
Any thoughts?


1956 Plus 4 4 seater
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From the perspective of operation, a wax type thermostat when it fails normally fails closed, an alcohol type thermostat usually fails open ( so they were considered the better option ). Alcohol types used to be slightly more expensive than the wax type, but wax types are more common.. That might explain cost, but it just might be a retailer milking the cost.


Dave
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I used to drill 3 small holes in the 'stat flange to allow some 'bleed' if it failed shut, ok the engine takes a little longer to warm up but used to be a bit of a hot summer / racing failsafe


Jon M
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The one in my Plus8 had these holes in it. I took it out to flush the system when replacing the coolant. Put it back in. It is a good idea as it allows a small flow through under closed conditions.

Last edited by sospan; 18/07/23 02:28 PM.

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A single 2mm hole in the thermostat rim positioned at the top also aids bleeding coolant after refill when thermostat otherwise closed. Some thermostats are supplied with hole in rim already and tiny split (jiggling) pin in same which aids the bleeding I'm told.


Richard

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Originally Posted by CooperMan
I used to drill 3 small holes in the 'stat flange to allow some 'bleed' if it failed shut, ok the engine takes a little longer to warm up but used to be a bit of a hot summer / racing failsafe
The cheap one from Rimmers doesn't have any holes in flange but the other two have. I ordered the OEM one which has one hole with a split pin.

Last edited by GrumpyPa; 18/07/23 07:41 PM.

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Make sure when you fit the thermostat you put the hole at 12 o'clock.


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Originally Posted by britmog
Make sure when you fit the thermostat you put the hole at 12 o'clock.
Not heard that before, please explain.


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Originally Posted by GrumpyPa
Originally Posted by britmog
Make sure when you fit the thermostat you put the hole at 12 o'clock.
Not heard that before, please explain.

Or perhaps more important ensure the drilled hole is oriented on supporting flange to be at highest point to aid self bleeding. If the thermostat flange lies in the horizontal plane it makes no difference of course.


Richard

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T
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12 o'clock standing where?🤔


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