Engine cooling flaps thermostat

[subheatadey]

I am going to install the cooling flaps in and the Engine cooling flaps thermostat is fekked, it looks like you can buy original and after market stats but the price seems 'mental' - did I mention I'm skint :shock: so just wondering if anyone knows where I can get oneat a reasonable cost for?

Tar

 

[Alex VW Heritage]

You can find them second hand but such a critical component i would try and get new:

https://www.vwheritage.com/shop/111119159A/thermostat-1-2-1-6-genuine-mod-for-type4-ct/" onclick="window.open(this.href);return false;

I know thats not the answer your looking for.

 

[gvee]

Might be worth giving Herbie's a ring.
If not, try Jez @ DubTricks.
Failing that, thegatekeeper on here would be worth a PM.

 

[KARL ARVID STENBERG]

hello

i buyed one off these which is brasil type

and it works very good

from gsf and half price of bellows type

you will need to cut top of thermostat bracket off

which is no big deal , i can send photo of mine to you to show how it is done

if you get stuck

http://www.ebay.co.uk/itm/Thermostat-for-VW-Beetle-Bug-Type-1-Transporter-T2-Type-3-Karmann-Ghia-/380658148484?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item58a0fe6484" onclick="window.open(this.href);return false;

karl

 

[subheatadey]

Cheers guys, yes a photo would be great Karl, didn't realise you had to cut part of the bracket to fit the modern thermostat I heard the later ones we not as good as the older ones?

Finally, are GSF still doing there 35% does anyone know?

 

[jonboylaw]

Alex,
The thermostat will fail in safe mode, ie it it is fecked it expands to let the air through. They are a very simple design, it the bellows are closed when cold then it will be functional. Do however check the brass thread is ok on the top and bottom.


Sent from my GX64 SatCom phone using Tapatalk

 

[Alex VW Heritage]

Alex,
The thermostat will fail in safe mode, ie it it is fecked it expands to let the air through. They are a very simple design, it the bellows are closed when cold then it will be functional. Do however check the brass thread is ok on the top and bottom.


Sent from my GX64 SatCom phone using Tapatalk

I know thats what is meant to happen but having seen several failures which resulted in the flaps staying shut cooking engines I am always a little nervous of seciond hand bellows.

 

[lhu128l]

I have a new (nos) bellows type1 thermostat still in box for sale if interested £45 posted .....its a wahler one

 

[vwcanuck]

Whether you buy new, NOS or find a nice used one, I'd do the "stovetop testing" method in this link to make sure that it works properly. It's a quick test that could save you an engine ... and it works!

http://www.ratwell.com/technical/Thermostats.html" onclick="window.open(this.href);return false;

 

[Trikky2]

If you study how these original type (Not Waxstats) thermostats work it will soon become obvious that testing them is futile.

If however a (mule headed) decision is taken to test one anyway - it should only be tested whilst fitted into its bracket, otherwise it will over expand, which will lead to metal fatigue and eventual failure.

Ratwell's pages are very good indeed but occasionally, as in most large amounts of information, there can be an error, this is one.

To keep your thermostat in good order keep it oily. The brass alloy can corrode - more so if salty.

 

[subheatadey]

Cheers Guys, got the bits i needed i shall test the thermostat as Tricky says when its in place but it looks good, didn't realise they were a wax-stat though I assumed they would be a sealed unit with an inert gas like ether or something?. I take on board what Alex has to say, the last thing i want to do is cook my engine so a temperature gauge is a must. I am also going to modify the bar that operates the flaps which i read someone had done and seems a good idea he welded a small extension piece to the bar so it protrudes and you can see it and then painted some marks on the doghouse so you can quickly check whether it is open and close.

Gearbox back in and packed the C.V joints to maybe squeeze some more life out of them today. Maybe get the engine in this week

 

[vwcanuck]

If you study how these original type (Not Waxstats) thermostats work it will soon become obvious that testing them is futile.

If however a (mule headed) decision is taken to test one anyway - it should only be tested whilst fitted into its bracket, otherwise it will over expand, which will lead to metal fatigue and eventual failure.

Ratwell's pages are very good indeed but occasionally, as in most large amounts of information, there can be an error, this is one.

To keep your thermostat in good order keep it oily. The brass alloy can corrode - more so if salty.

Even though VW produced vehicles that are simple enough for the common citizen to repair, it's a challenge for some of us to understand the many whats, hows and most importantly the whys involved to diagnose and repair problems and have our buses run safely on the road.

Why is it futile to test a thermostat?

 

[Trikky2]

Why is it futile to test a thermostat?

The brass bellows unit has a type of alcohol in it.

The "at rest" shape of the bellows is its extended shape.

During manufacture an alcohol is put in and the unit is heated until enough of the alcohol turns to vapour - when the vapour has displaced all the air inside, the small filler hole in the unit is sealed up with solder.

As it cools, the alcohol vapour condenses and sucks the bellows into compression - or to put it another way, the alcohol condensing into its liquid form reduces the pressure inside to considerably less than atmospheric pressure and hence the atmospheric pressure compresses the bellows. (Sort of like early condensing steam engines).

So, when the unit is heated enough for the alcohol to vaporise, the brass bellows can expand back to its normal size.

Heating it too much will over expand it so it should only be heated whilst in its bracket to stop this happening.

What this means is that if the thermostat is in its collapsed form when below about 70C then it is good. Any crack or leak will allow the thermostat to expand back to its natural extended shape.

Simple rule is if its short its good, if its extended its knackered :lol:

Hope this helps and that I have explained it well enough

 

[jonboylaw]

Most succinct, if it fails, it fails SAFE, unless the flaps are ceased closed, but unlikely on a well maintained engine.


Sent from my GX64 SatCom phone using Tapatalk

 

[chad]

Really good explanation - thanks

 

[vwcanuck]

Thanks Trikky! I think many of us don't know that there are two VERY different thermostats and this leads to confusion when our research does not specify which type is being discussed. There is the original bellows type and the new spring type. Now that you explained how the bellows type thermostat works, I would never use a spring type as it fails closed.

You were right about Ratwell and his useless thermostat test

 

[Trikky2]

You were right about Ratwell and his useless thermostat test

Well its just one error in a huge amount of info and I honestly think Richard Atwell's is an excellent source of info / is an important resource of information.

So please don't anybody be put off using it, its a gold mine of useful info.

 

[gas1man]

Then so are you. Sir. :lol:

J & P