thermostat

164runner

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does anyone know if ford would have installed a 180 or 192 thermostat in the 351c

 

midlife

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Ford almost always recommended and used a 192 thermostat.

 

Manu Mach1

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And you need the right thermostat, Robert Shaw 333 series or equivalent which seat on the restrictor plate.

 

164runner

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it has the correct thermostat with restrictor plate, cant remember what degree it is. with this new engine and in warm weather, seems to run warm in stop and go traffic. guess i pull thermostat and check it. robert shaw sells 160-180-192 thermostats.

 
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it has the correct thermostat with restrictor plate, cant remember what degree it is. with this new engine and in warm weather, seems to run warm in stop and go traffic. guess i pull thermostat and check it. robert shaw sells 160-180-192 thermostats.
 After confirming the thermostat is correct, mine is a Stant 190 deg. and I have the Derale 18" fan and Hayden fan clutch, you might want to check your timing set up.

As yet, I have not driven this fan assembly in very hot weather (not yet anyway). The only time I had it run hot was back in 2019. It was an extremely hot day and I got stuck in a long line of traffic crossing the border into Canada. I know I pissed off a few people, but all I had to do was up the rpms for a few minutes and the temp dropped back to normal, 190deg. 

 
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Most people think a colder thermostat will make engine run cooler but it is the opposite. The thermostat will never close if it is a cold one. The coolant does not stay in the radiator long enough to cool down so gets hotter and hotter. 192 is what you want. Does your hose going to water pump have a spring inside so it will not collapse?

 

SteveO_71

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reading material re spring in the lower hose that I came across from somewhere:





 


 




 


 




 
Original equipment molded radiator hoses often were equipped with a coil inside them. Some refer to this coil as a spring, but it isn't really a spring. Actually just a piece of thin metal rod that has been twisted, it was designed to facilitate the installation of coolant on the assembly line, and nothing more.

When the cooling system of a car is completely drained, or in the case of a brand new car under construction, never had coolant in it, there is a considerable amount of air in the passage ways. Normally, when filling up the cooling system, you start the car to circulate the coolant, displace trapped air, and then top it off. On the assembly line, this wasn't feasible, so air in the cooling system was evacuated by essentially pulling a vacuum on it. This also had the added advantage of speeding up the introduction of the coolant mixture to the cooling system as well. The coil in the lower radiator hose prevented the hose from collapsing under this higher than normal vacuum.

Once the car left the factory, the coil served no further purpose. This is why replacement hoses usually do not have a coil in them. Most cooling systems operate at 12-15 P.S.I., which is controlled by the radiator cap. This is enough pressure to allow a normally functioning cooling system to operate efficiently, yet not enough to cause collapsed hoses or leaks in seals if they're in good condition. If the lower radiator hose collapses, it is normally due to a fault somewhere else in the system, and is not necessarily indicative of a bad hose, although an old hose certainly might be susceptible to collapse due to age. Normally, if the hose is in good condition but collapsing and blocking the flow of coolant, the radiator cap is bad or there's a blockage somewhere else causing pressure to build up in the cooling system.

As vehicles with original hoses began to age, the coil would sometimes begin to corrode and deteriorate, circulating tiny pieces of metal throughout the cooling system. We'll leave it to your imagination what this did to water pumps and thermostats.

This is just one of many interesting stories about automobiles, the people who build them, and how they were built, brought to you by Automotive Mileposts.





 

164runner

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it has the correct thermostat with restrictor plate, cant remember what degree it is. with this new engine and in warm weather, seems to run warm in stop and go traffic. guess i pull thermostat and check it. robert shaw sells 160-180-192 thermostats.

got me a infrared thermometer, started to check radiator, engine temp. stock water temp gauge, think i will mount a gauge under dash and compare the two

 
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it has the correct thermostat with restrictor plate, cant remember what degree it is. with this new engine and in warm weather, seems to run warm in stop and go traffic. guess i pull thermostat and check it. robert shaw sells 160-180-192 thermostats.

got me a infrared thermometer, started to check radiator, engine temp. stock water temp gauge, think i will mount a gauge under dash and compare the two
Sorry, I don't recall if you mentioned your radiator condition. IF you have not done so, perhaps have the rad flushed and pressure tested. I had my rad rebuilt to a 3 core several year back and had no problem to speak of (other than when I got stuck at the Detroit/Windsor border on a 95 deg day!). This is just one more item to cross off the list. I would also consider it normal for the temp to increase slightly, but if it's going to near boiling, then something is definitely wrong for sure. 

EDIT: When was the water pump last checked, serviced or replaced? Maybe time to replace it.

By the way, I'm an expert at nothing, just throwing ideas out there. Good luck sorting it out.

 
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Don C

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reading material re spring in the lower hose that I came across from somewhere:





 


 




 


 




 
Original equipment molded radiator hoses often were equipped with a coil inside them. Some refer to this coil as a spring, but it isn't really a spring. Actually just a piece of thin metal rod that has been twisted, it was designed to facilitate the installation of coolant on the assembly line, and nothing more.

When the cooling system of a car is completely drained, or in the case of a brand new car under construction, never had coolant in it, there is a considerable amount of air in the passage ways. Normally, when filling up the cooling system, you start the car to circulate the coolant, displace trapped air, and then top it off. On the assembly line, this wasn't feasible, so air in the cooling system was evacuated by essentially pulling a vacuum on it. This also had the added advantage of speeding up the introduction of the coolant mixture to the cooling system as well. The coil in the lower radiator hose prevented the hose from collapsing under this higher than normal vacuum.

Once the car left the factory, the coil served no further purpose. This is why replacement hoses usually do not have a coil in them. Most cooling systems operate at 12-15 P.S.I., which is controlled by the radiator cap. This is enough pressure to allow a normally functioning cooling system to operate efficiently, yet not enough to cause collapsed hoses or leaks in seals if they're in good condition. If the lower radiator hose collapses, it is normally due to a fault somewhere else in the system, and is not necessarily indicative of a bad hose, although an old hose certainly might be susceptible to collapse due to age. Normally, if the hose is in good condition but collapsing and blocking the flow of coolant, the radiator cap is bad or there's a blockage somewhere else causing pressure to build up in the cooling system.

As vehicles with original hoses began to age, the coil would sometimes begin to corrode and deteriorate, circulating tiny pieces of metal throughout the cooling system. We'll leave it to your imagination what this did to water pumps and thermostats.

This is just one of many interesting stories about automobiles, the people who build them, and how they were built, brought to you by Automotive Mileposts.
I agree with this article. I have never replaced the spring in the lower hose if the new one did not come with one already installed. The water pump is not a positive displacement pump (like an air pump or air conditioner compressor), instead it is just an impeller spinning in liquid. It has very little draw (suction) and is not self priming and only functions because it is immersed. Just the weight of the coolant in the engine and radiator is enough to keep the lower hose from collapsing.  The lower hose functioned just fine back in the days before pressurized cooling systems.

 
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