Shewman's High Flow Thermostats

[Old Henry]

Just in case anyone wants to get the Stant stat for their engine here is some information about that. It is a Stant 14157 available on line many places including Amazon here: http://www.amazon.com/dp/B000C822YC or at NAPA part number THM 111, or at O'Reilly that sells the same stat as a Murray 4157, O'Reilly part number 2962.

[VeryTangled]

Wow that is GOLD.

Having a good time following this thread and learning a lot.

Prof. Henry, is there any chance you can post more photos when you get them? I'd be especially interested in seeing one in the open position.

I'd also be interested in their opening temperature, and their closing temperature. It seems you will be interested in them closing correctly as the fluid cools on descent, preventing the temperature from dropping into an abnormally cool operating range, after being open during ascent. As I read it this is one of the areas you're looking for to get good performance.

-VT/JeffH

[Old Henry]

I will give a full report with pictures upon receipt of them.

[ken ct]

Hope they work.If they do you better put that Barner on your yearly Christmas List.He has some generosity in droves. Good luck. ken ct.

[Old Henry]

Bought the Stant stat today and heated it up with the current replacement and here's what I learned.

Looking up through open stats.



Looking down through open stats in the water.


Just the appearance should convince of the higher flow of the Stant stat. If not, here's the data: The diameter of the opening above the valve for the water to pass through (the sharp metal edge) is 25 mm for the brass and 28 mm for the Stant. That alone is a 25% increase in space for the water to go through. The diameter of the valve plates is 27.5 mm for the brass one and 29 mm for the Stant. But, once that valve is out of the way that difference doesn't matter so much. The difference that really matters in the 25% larger opening of the Stant stat. Then you have the issue of the space above the valve seats that the water must pass through. That's where the biggest difference is as you can see in the pictures. Just eyeballing it I don't think the total area of the openings above the valve seat on the brass one is even equal to the area of the valve seat. So, the real restriction in the brass one is those openings that are so small. Whereas, as can be seen in these and the previous photos, there really isn't any restriction above the valve seat in the Stant stat. Those openings are clearly bigger than the area of the valve seat.

So, my analysis suggests that the Stant stat has at least 25% higher flow than the standard brass ones now being sold for the 59A engines and likely even higher. To increase the volume of the brass stat to that of the Stant one you'd have to drill thirteen 1/8" holes in the space between the valve plate and the inside of the head neck, if you could fit them in there. But then, of course, you'd have a defective and pretty much worthless thermostat. And, the Stant stats are 30% cheaper than the brass ones - $7.00 from most suppliers compared to $10.00 for the brass one.

[51 MERC-CT]

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The 12% sounds good but if you calculate the area of the openings you will find it to be more in the 25% range not counting the severe restriction on the brass one, then it looks more like 35-40% if not more.

[Old Henry]

Originally Posted by 51 MERC-CT

The 12% sounds good but if you calculate the area of the openings you will find it to be more in the 25% range not counting the severe restriction on the brass one, then it looks more like 35-40% if not more.

You're correct. I fixed my error in my post.

Thanks

[Bluebell]

So having come this far, Just how much flow is required, and why do much bigger engines (of much higher hp output) function well with half as many thermostats? (I know about the ex. ports)
How many gallons per minute will flow through the standard stat, fully opened? and how many gallons per minute are required to meet the needs to sufficiently cooling the FHV8?

[Talkwrench]

Bluebell I was thinking the same thing...

[VeryTangled]

Hi Everyone,

I found a "how it's made" type video on thermostats on Youtube. I learned some about the wax and how the melting wax causes the opening and how the spring causes the closing.

https://www.youtube.com/watch?v=xVPtIi6sVYg

-VT/JeffH

[Old Henry]

Originally Posted by VeryTangled

Hi Everyone,

I found a "how it's made" type video on thermostats on Youtube. I learned some about the wax and how the melting wax causes the opening and how the spring causes the closing.

https://www.youtube.com/watch?v=xVPtIi6sVYg

-VT/JeffH

Very good. I was wondering how they could sell what seems to be a complicated piece of machinery for $10.00. Cheap labor (machines).

That is also how Ford made the original thermostat for the 59A pressurized cooling system. (Pictures in Post # 44) However, Ford also made one differently for the non-pressurized systems - the 11A-8575-C. It used something else in the bellows that built up pressure under heat to open the valve and counted on a fixed pressure from the outside of the bellows to expand against, which it would not have had with a pressurized system.



Just out of interest, here are a couple more vintage stats.

The Dole adjustable stat that uses a bimetal strip to open and close.


And Fulton stats that work on the same principle as Ford's for non-pressurized systems:


(Pictures courtesy of my barn friend that sold me his NOS 78-8575-C's. Hope he doesn't mind.)

[ken ct]

Originally Posted by Old Henry

Very good. I was wondering how they could sell what seems to be a complicated piece of machinery for $10.00. Cheap labor (machines).

That is also how Ford made the original thermostat for the 59A pressurized cooling system. (Pictures in Post # 44) However, Ford also made one differently for the non-pressurized systems - the 11A-8575-C. It used something else in the bellows that built up pressure under heat to open the valve and counted on a fixed pressure from the outside of the bellows to expand against, which it would not have had with a pressurized system.



Just out of interest, here are a couple more vintage stats.

The Dole adjustable stat that uses a bimetal strip to open and close.


And Fulton stats that work on the same principle as Ford's for non-pressurized systems:


(Pictures courtesy of my barn friend that sold me his NOS 78-8575-C's. Hope he doesn't mind.)

I have a pr of 175 like in that last pic you show in my 36 and have another spare pr. And a pr of the ones with the big coiled flat spring near the bottom. ken ct.

[Bluebell]

Old Henry, those first ones in post #62 are bellows type stats.
If I recall they are alcohol filled.(I cant remember for sure)
Anyhow this might be of interest;
The wax stats normally fail in the open position, (a good thing) and the bellows type usually fail in the closed position (bad)
I dont think anyone is making the bellows type commercially anymore.

[Old Henry]

Originally Posted by Bluebell

The wax stats normally fail in the open position, (a good thing) and the bellows type usually fail in the closed position (bad)

I've heard that but can't figure out how the wax ones can fail in the open position when they have that spring holding them shut. What would make the wax expand against the spring when it fails?

Curious.

[peewee2you]

Okay here it goes, and I know I am going to ruffle a few feathers with this post, but I feel that it is worthy enough to say it, in hopefully helping a fellow barner before he's encounters what I did. This is just my experience and have not heard of anyone else having this problem so, maybe just me... but I am ept enough, not an expert to feel that there was no way possible this was going to work for my application which was from a stone stock standpoint. Shewman's thermostat's there is a photo on here and it's the stat on the right that I used, for 47 Ford 59AB block, I think and believe a stock radiator and aftermarket repro hoses w/ford script? Got the stat's and heated them up actually opened around 185 to 190, but I was okay with that.

My problem came where these stat's fit in the upper portion of the hose near the radiator and they slide inside the hose, no easy task even with dawn soap, didn't want to use anything and hammer on them to drive them in, now either my radiator necks were longer than should be, but I think not, I had to drive the stat so far in that it reached the curvature of the hose neck, which seemed odd, just so I could get the rest of the hose on the radiator neck far enough to sinch up the clamp.
I was uncomfortable with this because of the way the thermostat's open the bottom half of the stat pulls down or let say the inner portion of the stat, and I can see inside the hose to know if it was working or would not work because it was at the curve of the hose? The other side my passenger side, I couldn't get the thermostat ever in far enough to even get it on the neck of the radiator far enough to tighten a clamp? I work a day and a half spent money on various pieces' to use trying to drive them into the hose far enough to get on to the neck so I could try them out. Sorry but after 1.5 days frustration, anger, cussing, I decided anything that I had to work that hard at isn't going to happen, so yes I removed them...now that was another ordeal, because afterr I got them in there, I rinsed them out with a hose to get all the dawn soap out, so now you have a thermostat stuck way in a hose with friction binding of the brass, and rubber hose and trying to figure out how can I remove them now without damage... crap I was pissed. Now, all that being said I returned them and will never try that again with those stat's with my application. I am thinking also that everyone uses different types of hoses like those flex hoses, I can't imagine how it would work in those, but seems some of you have used them I got them installed on your car, how I don't know, like I said maybe it's me, and that's okay...hoping better luck for you if that's the route you decide to take...I have used Shewmans other products with good success...just not those.

[peewee2you]

in one section of my post I said I can see inside, and I meant that I couldn't see inside.

[Old Henry]

Originally Posted by peewee2you

in one section of my post I said I can see inside, and I meant that I couldn't see inside.

You can edit your posts to fix that kind of stuff. I do it incessantly. Just click on the edit button of the post you want to fix.

Thanks for telling your story. It needed to be told. There are some definite myths on this forum that need busted and the truth is what busts them.

Do you still have Shewman's stats that you could get some close-up macro pictures of like I've posted to show us and measure them to give us some dimensions?

[peewee2you]

Old Henry thanks for the editing tip, I must have missed that. I do not have them, I returned them. the pic on post #1 that you showed the picture of it was the one on the right, as I did not take any photo's of them. If I remember from the topside look like most of your standard type stat's. The bottom cylindrical half pulls downward allowing a nice 360 opening for the water to flow thru, I don't doubt that if you can get them properly installed they would work very well as stated.

[gearhead1952]

Great info Old Henry. Any thoughts for those of us running 49-53 engines? I found this on the napa website. It shows what they call a regular stat THM 70 and a premium stat THM 530060 both are 160 degree units. The premium stat looks in the pic to be less restrictive than the regular and very similar to the THM 111.

[51 MERC-CT]

Originally Posted by gearhead1952

Great info Old Henry. Any thoughts for those of us running 49-53 engines? I found this on the napa website. It shows what they call a regular stat THM 70 and a premium stat THM 530060 both are 160 degree units. The premium stat looks in the pic to be less restrictive than the regular and very similar to the THM 111.

This is the one you want--
http://www.summitracing.com/parts/bra-330-160/overview/