TheSamba.com :: View topic - Thermostat Air Flaps

Thu Nov 05, 2009 7:44 am

I just found the thermostat cable on my 1978 camper bus is frayed and broken plus the thermostat is not working. WIll order a new one and put it in but wanted to know, what is the default position when that cable is not connected? Closed or open. My Bentley book explains but isn't that clear. Can I still drive my bus without the thermostat?

Thanks

Pat Connolly

Thu Nov 05, 2009 7:45 am

Thermostat flaps are supposed to (designed to) fail open. Many of us drive without thermostats because they are increasingly difficult/expensive to get (myself included). Over the short run, there should be no problems, but over the long term, the lack of quick warmup is said to wear the engine excessively.

Thu Nov 05, 2009 7:56 am

So if the thermostat is not connected they default closed?

Thu Nov 05, 2009 7:58 am

They default open...it slows warm up, even prevents it in cold weather, but prevents over heating. Grab the spring bar and move it...you can feel yourself closing it and it springing back open if it's working right.

Thu Nov 05, 2009 8:00 am

It is the little spring on the rod ont he right side that is designed to hold them open when the cable breaks or should the thermostat fail.

Thu Nov 05, 2009 8:39 am

excellent! Thanks... now just will have to replace it. Was hoping for around 50 dollars but looks like new with the cable is about 110. Don't know if I should trust a used one off the classified for 40.

Thu Nov 05, 2009 8:53 am

If you're handy with mechanicals, there is a way to easily modify a type 1 thermostat, which are cheap and plentiful... a few searches here might turn it up.

Thu Nov 05, 2009 9:12 am

If you do find a good used one, you can just get a shifter cable from a bicycle shop. As mentioned, people also use "modified" T1 thermostat but I am not sure what is involved although GermanSupply says its a simple mod. I was looking around the other day and it looks like there is a new T1 thermostat available.
http://www2.cip1.com/ProductDetails.asp?ProductCode=VWC%2D043%2D119%2D159
Anyone tried one of these on a T4 yet?? GermanSupply has some original T1 thermos as well.
Cheers..

Thu Nov 05, 2009 9:31 am

kevin77westy wrote: If you do find a good used one, you can just get a shifter cable from a bicycle shop.

That is what I did, but it was a derailleur cable.

Thu Nov 05, 2009 11:10 am

I have the modified T1 on my bus and have not had any problems...works like a charm.

The install is straight forward and easy. The hardest part is pulling the cable up through the tin, pushing back the spring on the flaps (to hold it closed) and then tightening the set screw. Having a third hand here would help.

Thu Nov 05, 2009 11:18 am

If you're going to replace the thermostat, I would suggest trying to get a Mexican one. The original Bellows thermostats can be a crapshoot in terms of reliability.

I've bought two Bellows original thermostats, and the first one I ruined accidentally, but the second was a pain in the ass to get working properly, and it did only for about a month.

When the second one failed, it failed in the open position, which is good, because it took me a few days to notice.

I have read, however, that the Mexican ones can fail closed. How accurate that is though, I don't know.

Thu Nov 05, 2009 12:55 pm

Quote: Was hoping for around 50 dollars but looks like new with the cable is about 110. Don't know if I should trust a used one off the classified for 40.

$110 ????? where the heck were you looking? Many places sell them. Here is one $3.54 USD

http://germansupply.com/home/customer/product.php?productid=17057&cat=&page=1

Pelican Parts also has them for $6. A bicycle brake cable is very strong and inexpensive.

Look up this part number 021 119 751

Thu Nov 05, 2009 1:16 pm

I think he is talking about a thermostat, not the cable.

It would have to be one helluva cable for $110 though.

Thu Nov 05, 2009 1:59 pm

Fri Nov 06, 2009 8:48 am

Yes I fond one used for 10 bucks (they say it works so I'll take a chance) and my friend at a bike shop has given me bike cable. Thanks for all the help... Prepping the 78 camper for a trip to Maine next summer.

Fri Nov 06, 2009 8:54 am

RIOMX wrote: If you're going to replace the thermostat, I would suggest trying to get a Mexican one. The original Bellows thermostats can be a crapshoot in terms of reliability.

I've bought two Bellows original thermostats, and the first one I ruined accidentally, but the second was a pain in the ass to get working properly, and it did only for about a month.

When the second one failed, it failed in the open position, which is good, because it took me a few days to notice.

I have read, however, that the Mexican ones can fail closed. How accurate that is though, I don't know.

Yes they fail closed, I tried one a few years back, it was OK for around 6 months and started getting lazy, never again, garbage!

Fri Nov 06, 2009 10:41 am

I wouldn't be afraid of a used thermostat if you get a chance to look at it before buying. The thermostat should work if it has not failed and it is very simple to see if it has failed.

If you can easily squeeze it closed tighter than it is at rest, it has failed. If it looks compressed and you can't squeeze it tighter, then it is good.

DJ Roberts

Fri Nov 06, 2009 10:51 am

drober23 wrote: I wouldn't be afraid of a used thermostat if you get a chance to look at it before buying. The thermostat should work if it has not failed and it is very simple to see if it has failed.

If you can easily squeeze it closed tighter than it is at rest, it has failed. If it looks compressed and you can't squeeze it tighter, then it is good.

DJ Roberts

The second one I bought was perfect. Nothing about it seemed damaged or abused.

However, at some point it just decided it wasn't going to compress anymore.

I think their age really does make them risky to run when they haven't been used in years.

Fri Nov 06, 2009 12:27 pm

Iam always putting the flaps back in aircooled's (Iam doing one today) I just don't know why so many deside just pull-em out and toss them and I live in Alaska.

Fri Nov 06, 2009 3:11 pm

That's not smart...
If the flaps are not installed, the oil cooler gets no cooling air.
Better to have them installed without the thermostat...