Shewman's High Flow Thermostats

VeryTangled said:
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
Click to expand...

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.

Picture479-R_zpsb76b20cf.jpg


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

The Dole adjustable stat that uses a bimetal strip to open and close.
Picture480_zps44bf74cc.jpg


And Fulton stats that work on the same principle as Ford's for non-pressurized systems:
Picture482_zps9f78a283.jpg


(Pictures courtesy of my barn friend that sold me his NOS 78-8575-C's. Hope he doesn't mind.)
 
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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 said:
in one section of my post I said I can see inside, and I meant that I couldn't see inside.
Click to expand...

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?
 
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Old Henry said:
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.

Picture479-R_zpsb76b20cf.jpg


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

The Dole adjustable stat that uses a bimetal strip to open and close.
Picture480_zps44bf74cc.jpg


And Fulton stats that work on the same principle as Ford's for non-pressurized systems:
Picture482_zps9f78a283.jpg


(Pictures courtesy of my barn friend that sold me his NOS 78-8575-C's. Hope he doesn't mind.)
Click to expand...
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.
 
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.
 
Bluebell said:
The wax stats normally fail in the open position, (a good thing) and the bellows type usually fail in the closed position (bad)
Click to expand...

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.
 
I have never cut one of the pellets open, but I think the wax just leaks to the other side of a piston. Anyhow, I have removed a few over the years and that is how I found them. Stuck open.
 
Maybe it has something to do with the metals that they mix in with the wax that swell up when the wax is gone. Interesting.
 
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.
 
Old Henry said:
Here's what all modern thermostats are competing against - Ford's original design.

Picture481-R_zps9ea91e0a.jpg


These are NOS Ford stats for my 47 that a very kind barner has offered to sell to me. Just compare them with the modern stats and you'll see the real advantages of them. They have a butterfly valve that swivels clear out of the way of water flow. And, look at the size of that hole once it's opened up! Way bigger than any modern stats. And, the mechanism that opens it is small and much less intrusive into the water flow than modern stats. This is what I've been looking for and believe that, if they still work (I'll test before installing), they will work better than any modern substitutes for those reasons.
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Received these NOS stats from a barn friend. They work fine opening at their 180° specs.

The butterfly valve closed.
DSCN0905_zps776d0c65.jpg


Fully open.
DSCN0897_zps3a574002.jpg


The spring that pulls it shut rather then pushing it like modern stats.
DSCN0910_zps5c2034ff.jpg


This Ford NOS stat has an opening of 29 mm compared to the modern replacement of 25 or even the Stant of 28. That's 7% higher volume than the Stant and 34% higher than the current replacements. Too bad no one makes 'em like this any more.
 
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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 said:
This is the one you want--
http://www.summitracing.com/parts/bra-330-160/overview/
Click to expand...

Robertshaw made the original 330-160, 170, 180 stats. They were sold to Cooper Tire and Cooper sold out to a company that from what I understand
is having them made in Mexico. The materials have been changed and I have had reports of quality problems. Bob Shewman has a supply of the original
330-180 Robertshaw stats made for military truck applications. These were manufactured under government inspections and tests and are made of ALL heavy duty copper and brass with no substitute materials like the new copies being made now. These are what he modifies for the old Fords and retests every unit before shipping. These are the best stats available for the 1932 to 53 Fords as they are high quality and have the least restriction of other modern stats. I have tested them in a number of old Fords in temperatures over 95 degrees and the engines all run at 178 to 182 on both sides. G.M.
 
In looking at the pics of these high flow stats they look like they have large openings on the top but the bottom looks very restrictive am I missing something?
 
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