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Moseso
Jedi Knight
Offline
I offer to the collective wisdom of the Board my symptoms:
(I really liked BGbassplayer's post in the 160,000 posts thread: "My Triumph blah, blah, blah. Help!")
I installed a used, but tested, sleeve-type t-stat in my car as part of the restoration. I should add, at this point, that I tested the temp gauge in the same pot of water as the t-stat: it works well. Lackluster performance eventually led to the installation of a bypass hose restrictor -- great improvement.
Here's the essential wiggliness that I can't understand: When I start from dead cold in the morning, the motor runs hot, and heats up rapidly to near the third bar on the temp gauge when allowed to idle. Sounds like a partially open t-stat, doesn't it? After I let the car sit for 10 minutes, or more, the cooling system behaves <span style="font-style: italic">perfectly</span> -- and will continue to do so as long as I don't allow it to cool all the way down.
Weirdly defective t-stat, I think. So, this morning I replaced it with a NOS Smiths un-sleeved bellows type t-stat that I picked up during the three year eBay parts binge that accompanied working on my my project. It DOES THE SAME THING! First run: HOT. (Hotter than the one that I just replaced.) Come home -- wait 15 minutes. Second run: Couldn't ask for more. The car runs at 190 on a 90-degree day; in traffic, on the freeway, sitting at red lights. If it starts to creep up at a long signal, it drops right back down as soon as I begin to move.
Any one care to posit a theory? Why does my car run hot, until I stop and let it sit -- and then it runs fine?
I should add -- Of course, when I let the car sit, the temp at the t-stat housing first becomes very hot (above the third bar on the gauge) due to the hot motor and no-longer circulating coolant. That's been my only guess so far -- that the t-stat, exposed to very high temps, finally opens fully and then continues to operate as designed. But why both of them? That's too weird.
(I really liked BGbassplayer's post in the 160,000 posts thread: "My Triumph blah, blah, blah. Help!")
I installed a used, but tested, sleeve-type t-stat in my car as part of the restoration. I should add, at this point, that I tested the temp gauge in the same pot of water as the t-stat: it works well. Lackluster performance eventually led to the installation of a bypass hose restrictor -- great improvement.
Here's the essential wiggliness that I can't understand: When I start from dead cold in the morning, the motor runs hot, and heats up rapidly to near the third bar on the temp gauge when allowed to idle. Sounds like a partially open t-stat, doesn't it? After I let the car sit for 10 minutes, or more, the cooling system behaves <span style="font-style: italic">perfectly</span> -- and will continue to do so as long as I don't allow it to cool all the way down.
Weirdly defective t-stat, I think. So, this morning I replaced it with a NOS Smiths un-sleeved bellows type t-stat that I picked up during the three year eBay parts binge that accompanied working on my my project. It DOES THE SAME THING! First run: HOT. (Hotter than the one that I just replaced.) Come home -- wait 15 minutes. Second run: Couldn't ask for more. The car runs at 190 on a 90-degree day; in traffic, on the freeway, sitting at red lights. If it starts to creep up at a long signal, it drops right back down as soon as I begin to move.
Any one care to posit a theory? Why does my car run hot, until I stop and let it sit -- and then it runs fine?
I should add -- Of course, when I let the car sit, the temp at the t-stat housing first becomes very hot (above the third bar on the gauge) due to the hot motor and no-longer circulating coolant. That's been my only guess so far -- that the t-stat, exposed to very high temps, finally opens fully and then continues to operate as designed. But why both of them? That's too weird.
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