Spring goes in the intake manifold. Pointed triangle looking tip goes toward front radiator.

 

The upper hose is SUPPOSED to be hot and solid because when the thermostat opens, the hot coolant from the block though the upper hose TO the radiator and FROM the radiator thru the LOWER hose back to the block. 210 isn't overly hot.

 

A 195* thermostat is not fully open until about 210-212*F. And, yes, 210* is damn hot... you wouldn't want to stick your hand in a pot of boiling water, would you? The pressure in the system, up to 13 psi, will make the upper hose "stiff".

 

I appreciate all the feedback. It’s a mr gasket high performance thermostat. Just not sure it’s properly opening. All other radiator hoses when the thermostat opens you can squeeze them and they have some give to them because of the open flow of fluid, with it being so stiff it makes me wonder 1. I still have a few air bubbles in the system or 2. The new thermostat is trash and not opening regardless of temp and that is why the upper hose is rock solid with pressure.

 

I appreciate all the feedback. It’s a mr gasket high performance thermostat. Just not sure it’s properly opening. All other radiator hoses when the thermostat opens you can squeeze them and they have some give to them

well I woodent want my hose to have some give when squeezed

 

If your worried about the temp use a 180* thermostat and see what happens.. But if you run it in the winter your going to not have the heat your going to want..

 

REmember, the water pump pumps through the motor then out the upper hose. Its gonna be hot and stiff if its flowing - pause for tasteless jokes to clear from your head ........................................................................................ I do not see that as a problem in and of itself. The bottom hose has the pump pulling so it will likely be softer as the rhythmic pulsating from the water pump .................................................................................................... is damped through the radiator...

You guys - get your mind outta the gutter - seriously!

M

 

The lower hose being soft is also why there’s a spring coil in it or supposed to be to keep it from collapsing..

 

Maybe I’m just overthinking it. When I get off work today I’m going to fire it up with the radiator cap off and verify flow

 

Be sure to keep a rag around the water neck when you check flow. I had issues with the Mr. Gasket Performance thermostat. The rubber seal expands and it can't regulate the temperature. It stays partially open.
They are a cheap Chinese copy of the Stewart EMP high flow thermostat. I also run a 180 degree thermostat.
There are no issues with heat in the car. However, if you're in extremely cold climate it may.

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They are both copies of the Robertshaw thermostat. You wouldn't want the thermostat from Stewart with the holes drilled in it. Thats defeating the purpose of the thermostat. A Robertshaw thermostat flows vastly more than a standard one. Holes increase the amount of time an engine takes to warm up and may actually impede it from actually reach the correct operating temperature.

I too had issues with the Mr Gasket version. I had two different ones (180 degree) open way early my car couldn't stay above 160 while driving.

@66fasty if you have issues with it down the road. Buy a quality version of the Robertshaw. I have one from flowkooler that works great. If you bought yours from the parts store its most likely a 180 degree. They rarely have 195 on the shelf.

 

Fired up the car and let it run once it got hot with the radiator cap off it started bubbling out the top, so I had to put the cap back on, so as not to spill out all over the place. Once I put the cap back on the overflow tube off the side of the radiator let maybe half a cup of fluid.

 

Did you start it up cold? Or do it after it was warm? You do have to allow for some expansion. Most of us fill them up about an inch over the tubes. I don't remember if the Mr. Gasket version has it, but the Stewart EMP has three vent holes so there isn't a concern with trapped air.

 

Drain into a small pale on the ground.

 

Started it up cold, aware that the fluid expands but the bubbling makes me think air is still in the system

 

I have never experienced trapped air. I've been working on Mustangs for 49 years and never seen it. After working on it and topping it off to just over the fins, I always start the car with the cap off. I wait until the thermostat opens. The level always drops. I add until I'm back just over the fins. Install radiator cap and I'm done.

 

Here is what I do. I check all thermostats by heating them up in a pot on the stove and watch the thermostat open and later close. To avoid trapped air I drill a small hole at the 12 o’clock position. During installation I hold it in place using a rubber band.

A 180 thermostat might lead to the case your engine running to cool.


Sent from my iPhone using Tapatalk

 

The title of your post indicates thermostat direction which implies that perhaps you question if you did indeed have it installed correctly. First reply outlined the "direction." But I did not see in any of your susequent posts that you knew you had installed it properly.

 

I agree with Mustang4SF. Some thermostats come with the air bleed hole. If not I drill one in, place at 12'oclock position. With radiator cap off and no catch tank, level should be about an inch over tubes or inch from the top. When thermostat opens you should see flow in the radiator and you should be able to squeeze the top hose and see the flow change with your squeeze. Woodchuck was saying that the hose would be hard with the cap ON and the system under the 13-14 psi system pressure. If you have an overflow catch tank, with the engine cold, when you open the radiator cap the level should be all the way to the top. Many say 210 is not to hot. Whatever temperature thermostat you have installed, when you turn the engine off, does your car spit antifreeze out. If so, it's running to hot.

 

when you turn the engine off, does your car spit antifreeze out. If so

IT IS OVERFULL !

Fixed it for you.

 

I've never had to put an extra hole in a SBF thermostat. The little bypass hose in the thermostat housing is more than adequate to pass coolant (and air bubbles) through...there's more than enough turbulence ahead of the thermostat to prevent a bubble from forming.... I've always had success with pointing the nose up hill and running with the radiator cap off through a couple cycles of thermostat "modulation" and topping off the rad.

 

I know you remember when many T-stats lacked any type of venting. The Robert Shaw/ Stewart EMP works great with the hot FE engine and the High flow Edelbrock water pump.
The Mr Gasket copy of the Robert Shaw unit rubber seal expanded and kept the unit open all the time so as you stated: Less than 50 degrees out the engine stayed cold while at constant cruise. It was open about 1/4".

 

I just had to check back in this thread to see how thermostat direction could warrant 24 posts, lol.

 

Glad to know I'm not the only one here for the same reason...