Slant Six Forum :: Thermostat in backwards

Hi krytellan.
If the thermostat is in the upside-down position, one should believe that it should not open at all! But, that is not entirely true. Looking at the action of a thermostat, it is a temperature dependent expanding or contracting coil that moves the valve to open or shut for hot water. The fact that the coil is on on the incorrect side, usually doesn't make it stop working, it just takes a lot longer time before it reacts initially. The construction of the thermostat also dictates how difficult it is to open the valve against higher water pressure on one side. Once open, the coil itself is in the hot water stream, and should remain open without any problems for the cooling system.

Before fitting the new thermostat, you should reverse flush out the entire cooling system - including the heater circuit - with clean water; seeing how a previous owner treated the car should make you raise questions on all parts of servicing or repairs ever done to your car! Then refill it with a proper amount of antifreeze, which also acts as a lubricant for you water pump, and clean water. As this is a car you're going to keep for the rest of your life (no??), it is worth while to treat your cooling system to a flush and new fluid on a regular basis.

You should also drill a small hole (app.1/16") in the thermostat's flange before fitting it. That will prevent air from being trapped behind the thermostat, and it will make no difference to the thermostat's function.

Regearding the correct temp thermostat to use, I finish with a quote:

Quote:

I would run a 195 in it. Keeps engine temp up=more power and more MPG. Lowers emissions. Makes it harder to over heat. HOW? Slows down the water going through the radiator which gives it more time to loose heat. Running with out a thermostat will over heat-water runs through radiator to fast and can't give up its heat. If you have a after market over flow tank you can fill it to the top. If you are running a totally stock radiator then you need to fill to no higher than 2" below the filler, you need to leave room for thermal expansion.

Olaf.

Author:	wjajr [ Fri Jan 28, 2011 2:43 pm ]
Post subject:
Shade tree meets white coat ideal conditions: Sometimes the best â€œpremoâ€ part is not readily available locally, or the job at hand has to get done asap., will often dictate what is used. In other words, one works with what he has at hand. In my case, nearest part store is ten miles distant, others with higher grade lines 12 - 15 miles. Iâ€™ll not drive the extra ten for a stinking thermostat when in a pickle. With a non notched, or other wise non self bleeding thermostat that one often finds at his local auto parts supply, I still drill a small hole to aid in refilling cooling system. Without that bleed, it takes forever to get the head filled with coolant if thermostat has a good tight seal. Just donâ€™t put the damn thing wrong way inâ€¦ Donâ€™t tell me to leave out thermostat and fill head to bottom of its housing, fine advice for a non clean painted engine, but sucks for those of us trying to keep a clean machine. I just as soon keep the overflowing mess to the radiator area, not the front of and length of block. If you use readily available colbalt or other drills rated for hardened steel, drilling stainless steel will not pose a problem. Goes through it like buddah. Dan: [quote]Quote: [quote]And ALL manufacturers of poppet type thermostats must have missed Dan's opinion about the lack of different pressures in a cooling system[/quote]! An imaginative assertion, but not one I'm inclined to spend any effort or time trying to decipher.[/quote] Than donâ€™t. Itâ€™s easy, water pump exerts constant pressure in direction of flow, and slightly lower pressure or vacuum on suction side of pump within a closed loop system cooling system. This takes place with or without an open thermostat, and is why coolant is circulated faster than by convection alone.

Author:	hantayo13 [ Fri Jan 28, 2011 4:14 pm ]
Post subject:
what the hey !!!!! just fill block take out rad,fan water pump ....only goona run for a minute,maybe two for a 12 sec pass hehehehe keep on roddin'

Author:	olafla [ Sat Jan 29, 2011 4:06 pm ]
Post subject:
Quote: The construction of the thermostat also dictates how difficult it is to open the valve against higher water pressure on one side Quote: The reverse poppet thermostat This thermostat type opens against the flow of coolant from the water pump, and uses the pressure from the water pump to assist in keeping the valve closed, thus reducing the possibility for leakage when cold. Quote: ...The thermostat is not responsive to water pressure, and there is no "higher watter pressure on one side"... ...More to the point, though, the thermostat does not respond to a difference in pressure on either side of it. Take a look at how it's mounted; it opens opposite the direction of flow, not with the direction of flow, so it's not going to be pushed open by coolant flow... Dan, I interpreted wjajr's response as a comment/correction to your attack on what I wrote. And when one of the very points of making a balanced-sleeve thermostat is that the design prevents the thermostat from being influenced from differences in pressure: Quote: These high performance thermostats are designed to resist large variations in coolant pressure that occur at high RPM's where coolant temperature and coolant pressure fight for control of the thermostat keeping it from opening at its designated temperature. Come on Dan! Is this your way of presenting what you claim to be correct information? This is starting to get real stupid. Olaf.

Author:	kielbasa [ Mon May 01, 2017 11:55 am ]
Post subject:
Just picked up a 45358 superstat. This so called premium thermostat that in dans description should have a jiggle pin or a notch. It in fact does not. I vaguely remember this with the original thermostat I installed. I believe it's failing (very irratic overheating and temp fluctuating) so I picked up a new one. Would you suggest drilling the hole? I belive I did last time aswell.

Author:	SlantSixDan [ Mon May 01, 2017 3:54 pm ]
Post subject:
Some engines are prone to air entrapment, and in those applications a jiggle pin or bleed hole is necessary. The Slant-6 is not such an engine. Don't worry about it -- don't drill it -- just go ahead and install it.

Slant Six Forum https://slantsix.org/forum/

Thermostat in backwards https://slantsix.org/forum/viewtopic.php?t=43394	Page 2 of 2

Author:	SlantSixDan [ Sat Jan 29, 2011 10:07 am ]
Post subject:

Author:	emsvitil [ Mon May 01, 2017 5:14 pm ]
Post subject:
If you look closely, there's usually a ting notch in the thermostat that works as the air escape...........

Author:	SlantGeek [ Mon May 08, 2017 1:31 pm ]
Post subject:
Quote: Hi krytellan. If the thermostat is in the upside-down position, one should believe that it should not open at all! But, that is not entirely true. Looking at the action of a thermostat, it is a temperature dependent expanding or contracting coil that moves the valve to open or shut for hot water. The fact that the coil is on on the incorrect side, usually doesn't make it stop working, it just takes a lot longer time before it reacts initially. The construction of the thermostat also dictates how difficult it is to open the valve against higher water pressure on one side. Once open, the coil itself is in the hot water stream, and should remain open without any problems for the cooling system. Before fitting the new thermostat, you should reverse flush out the entire cooling system - including the heater circuit - with clean water; seeing how a previous owner treated the car should make you raise questions on all parts of servicing or repairs ever done to your car! Then refill it with a proper amount of antifreeze, which also acts as a lubricant for you water pump, and clean water. As this is a car you're going to keep for the rest of your life (no??), it is worth while to treat your cooling system to a flush and new fluid on a regular basis. You should also drill a small hole (app.1/16") in the thermostat's flange before fitting it. That will prevent air from being trapped behind the thermostat, and it will make no difference to the thermostat's function. Regearding the correct temp thermostat to use, I finish with a quote: Quote: I would run a 195 in it. Keeps engine temp up=more power and more MPG. Lowers emissions. Makes it harder to over heat. HOW? Slows down the water going through the radiator which gives it more time to loose heat. Running with out a thermostat will over heat-water runs through radiator to fast and can't give up its heat. If you have a after market over flow tank you can fill it to the top. If you are running a totally stock radiator then you need to fill to no higher than 2" below the filler, you need to leave room for thermal expansion. Olaf. Hey krytellan, Mopar mechanic with http://www.buttondodge.com/ here. I definitely agree with Olaf. I haven't ever seen a thermostat in upside down but I have heard about it. The symptom was that the car took a long time to warm up! As Olaf explained, the heat would eventually get to the mechanism but it will take longer. Best, Thomas

Author:	SlantSixDan [ Mon May 08, 2017 4:41 pm ]
Post subject:
Do not drill a hole in your thermostat. It will not help, only hinder. Use a good quality thermostat of the optimal temperature rating (see here), install it right way round and rightside-up (if applicable), and call it good. There are some engines with cooling systems it's very difficult to bleed all the air from, that require thermostats with air bleeds, special air bleed procedures after coolant drain and fill, etc. The Slant-6 is not one of these engines.

Author:	rich006 [ Wed May 10, 2017 8:58 am ]
Post subject:	Who is SlantGeek?
Not to hijack the thread, but SlantGeek: who are you? In each post you claim to be a mechanic at some Mopar dealer, but a different one each time. Are you being paid to advertise for them?

Author:	crickhollow [ Thu May 11, 2017 3:54 am ]
Post subject:
One sunny day a young bull and an old bull were walking down a country lane when they spotted a herd of cows. The young bull said to the old bull - "hey look at all those cows, lets race over there and #### a few of them". The old bull wisely replied - "lets walk quitely over there and we will @@@@ the lot".

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