Grill Shutter Thermostat 1931 Chrysler CD8

[jekeys1]

As the title says, I have a 1931 Chrysler CD8, but I'm having issues with the thermostat controlled grill shutters. The shutters stay closed most of the time, only opening once the car gets up to 210 degrees. I would think they should open alot sooner. This was on a 65 degree day too, wouldn't be good if it was 90 out. I have noticed a few other posts where they talk about this, and they've said you should not be able to move the shutters in 100% cold or 100% warm, but you may move them slightly in the middle. Well I can move the shutters whenever I want, just take quite a bit of effort.

My main question, is there a way to adjust when the thermostat opens the shutters, so at a lower temperature? Or is thermostat junk?

Thanks in advance,

Jeff

[keiser31]

Seems to me there is a thread on this forum about those units and where to get them reconditioned. You might use the "Search thread" button and see what shows up. You might scroll down to the Chrysler section and the Dodge Brothers section. The 1931 DG8 has a similar control.

[jekeys1]

Already did, not much luck.

[Guest Commodore]

Here is a source for the thermostat. Not cheap.

http://www.hirschauto.com/prodinfo.asp?number=SYL-4

This maybe the thread that Keiser31 was talking about.

http://forums.aaca.org/f134/sylphon-thermostat-repair-259071.html

[jekeys1]

Those are 2 good links. Didn't come across those ones yet.

[Friartuck]

The original poster says it works just at a hotter temp, meaning its still is a sealed unit. Likely it lost its alcohol. You must use Ethel Alcohol. If you pull the unit you should find a small hole soldered over. Unsolder the hole, add approximately 25-30 percent of the units volume with Ethel Alcohol and resolder the hole. Test in a pot of water on the stove, while keeping track of the temp and the units movement. If the temp that makes it move is still too high, add more alcohol. You must use Ethel Alcohol, not Isopropyl alcohol. Ethel has the lowest boiling point of the family of alcohols. When the alcohol boils, it expands against the bellows, hence why it must be sealed to work. Ethel alcohol is available at hobby shops or science/lab suppliers. Hint: Methanol Alcohol is used in Dry Gas and could be used, though I would wait for the right stuff.

If you wanted, you could use a blow gun with rubber tip against open hole before filling to perform a leak down test. Start with no more than 5 PSI and observe the movement of the bellows. If it doesn't hold, there's a leak that must be sealed.

Edited October 3, 2014 by Friartuck (see edit history)

[Guest AlCapone]

I also have a 1931 CD 8 and I have experienced the same problem. 10 years ago a very old Chrysler mechanic told me to forget it because they never ever worked properly. Wayne

[jekeys1]

Friartuck, thanks for answering my initial questions, very helpful thanks.

[Linus Tremaine]

I agree with friartuck that you can probably repair this by refilling the bellows with new alcohol and re soldering. However, the bellows inside are as old as your car and will eventually fail. Jim Otto is 80 years old and he is, as far as I know, the only person rebuilding these. He worked for the Fulton Bellows company for his whole career. He has amassed a collection of NLA bellows that he can modify to fit these units. I think you should have yours repaired. I just had mine done on my lincoln. I think it cost 232.00.

His phone number is in the thread that was mentioned above by friartuck.

[Joe in Canada]

I was at Hershey this year and a vender sold me a defective one saying if you have movement in the bellows it will not work. The other defective ones I have also have downwards movement. I also have an NOS one still in the box and that one the bellows will not move and when I shake the NOS one you can hear the fluid inside. Now my question is do you have to take it apart and stretch the bellows to touch the bottom. I have taken one of my old ones apart out of curiosity to see what I am dealing with.

[dep5]

I cheated, on my '32 Imperial I blocked my shutters open and use a conventional thermostat to maintain my engine temperature.