Can you run thermostat flaps fixed open w/o bellows?

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GasDaddy140
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Can you run thermostat flaps fixed open w/o bellows?

Unread post by GasDaddy140 » Tue Aug 01, 2017 12:43 pm

Hi Corvairs,

I've found that I only have one working bellows thermostat. What if I eliminate both bellows and fix my flap doors open full? It seems that the engine would take a little longer to warm up, but wouldn't it run fine afterwards?

Thank You.
Alan Duquette
Rohnert Park, CA
"When in doubt...Hit the gas!" A.J. Foyt.

1965 Corvair Corsa (field find) I will build my ship that comes in.
1971 Dodge Sportsman "shorty" 318 van
2015 Nissan Juke S

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azdave
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by azdave » Tue Aug 01, 2017 12:57 pm

GasDaddy140 wrote:
Tue Aug 01, 2017 12:43 pm
Hi Corvairs,

I've found that I only have one working bellows thermostat. What if I eliminate both bellows and fix my flap doors open full? It seems that the engine would take a little longer to warm up, but wouldn't it run fine afterwards?

Thank You.
Yes. You just have to be sure your engine regularly gets hot enough to burn off oil contaminates like fuel and water vapor. You will need the thermostats in cooler climates but I don't run them in Phoenix.

Looking at temps where you live (Northern California) I think you probably want to get them fixed if you drive in the winter.
Dave W. located in Gilbert, AZ
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
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65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed

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GasDaddy140
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by GasDaddy140 » Tue Aug 01, 2017 3:22 pm

Hi AZDave,

I prefer to fix them, however not at $60.00 or more a pop with no guarantee that the ones purchased will actually work, and no returns! Until winter time, I'll affix as open and try to find working used ones. Thanks again!
Alan Duquette
Rohnert Park, CA
"When in doubt...Hit the gas!" A.J. Foyt.

1965 Corvair Corsa (field find) I will build my ship that comes in.
1971 Dodge Sportsman "shorty" 318 van
2015 Nissan Juke S

Jerry Whitt
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by Jerry Whitt » Tue Aug 01, 2017 5:56 pm

Not having the thermostats will cause some other issues. The choke plates will not open as the engine "slowly" warms up. In turn the fast idle won't work properly. Then when trying to accelerate you will likely have a slow response. Your gas mileage will also deteriorate. Order some new parts and eliminate the headaches.


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Mac007
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by Mac007 » Mon Aug 07, 2017 3:11 pm

The local Corvair guy here removed and took my complete and working thermostats and doors saying I did not need them.


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my65
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Joined: Tue Dec 01, 2015 12:20 pm
Location: porter texas

Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by my65 » Mon Aug 07, 2017 6:17 pm

It depends where you live. In Houston the winter temperature averages about 53 degrees. So the engine warms up quickly and you don't need much of a heater (except for the defroster) ? Neither my 63 140 hp nor my 65 110 hp have them and my chokes open in two or three minutes. If you live where it get cold, I do not think I could get away without them.
Ed ( my65 )
65 Monza Convertible
110 HP 4 Speed
63 Monza Coupe
140 HP 4 Speed
Porter, Texas

WinginEngineer
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by WinginEngineer » Tue Aug 08, 2017 1:03 am

I have considered thermostatically controlled linear actuators with a linkage to the flaps so it can be mounted externally. The whole set up would still be half the cost of the bellows and it would be as reliable as the actuators... and i could get replacements.

Only catch is, like Dave said, i don't really need it here in phoenix. That said, my first 30 degree morning come january and i'll probably be down there doing my thing.

Just search linear actuators on amazon or ebay and get creative. A standard thermostatic switch for a fan should work fine (i usually get them from Jegs). Just remember, you need to keep the actuators outside of the tins. Most of them are rated a solid 100-150 degrees F LESS than the average temps in the lower "ducts".

When I get mine rigged up I'll post the design up on here for other folks to use it, but like i said, it'll be 6 months before i get there.
Kevin - Maricopa/Mesa, AZ
1962 Corvair 700

Gearfinger
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by Gearfinger » Wed Aug 09, 2017 6:14 am

Ken Hand say's "Remove the flaps". Drops mic, walks off stage...

Wagon Master
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by Wagon Master » Wed Aug 09, 2017 1:59 pm

Mac007 wrote:
Mon Aug 07, 2017 3:11 pm
The local Corvair guy here removed and took my complete and working thermostats and doors saying I did not need them.


I would go and politely ask for them back. :assault:

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66corsaguy
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by 66corsaguy » Wed Aug 09, 2017 5:24 pm

Mac007 wrote:The local Corvair guy here removed and took my complete and working thermostats and doors saying I did not need them.


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Hopefully it's not the corvair mechanic in San Francisco cos he ripped me off! I would never suggest anyone use him unless you have a minor problem and expect to wait months even for that.


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Frank DuVal
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by Frank DuVal » Fri Aug 11, 2017 8:45 pm

Here in Virginia, we remove the lower shrouds for summer and put them back with working thermostats for the winter. Of course if one only drives in nice weather, then the thermostats are not needed. :tu:

Frank DuVal

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GasDaddy140
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Re: Can you run thermostat flaps fixed open w/o bellows?

Unread post by GasDaddy140 » Sat Aug 12, 2017 8:16 am

Fortunately, I got both of those flaps working, an adjustment problem, one was closed very tightly.

Mac007 wrote:Mac007 wrote:
The local Corvair guy here removed and took my complete and working thermostats and doors saying I did not need them.

Corvair thief's at the very least should be hit upside the head with a blower housing and bearing unit a couple of times.
Alan Duquette
Rohnert Park, CA
"When in doubt...Hit the gas!" A.J. Foyt.

1965 Corvair Corsa (field find) I will build my ship that comes in.
1971 Dodge Sportsman "shorty" 318 van
2015 Nissan Juke S

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