To disable cooling flaps or not, The endless debate Options

[Superhawk996]

ditch the stat.

Cabman - love ya to death but please stop propagating the ditch the thermostat advice.

The flaps and thermostat are there for a reason.

The majority of engine wear occurs during the warmup phase of operation this is true of all engines and is backed by decades of SAE research and documentation.

Disabling flaps and delaying warmup results in accelerated wear.

Even worse, air cooled engines depend on expansion of the heads to increase clamp load between the cylinder and the head as the engine heats up. Delaying warmup results in more likelihood of blowby between the head and cylinder and between the cylinder and the case.

And even worse yet on a carbureted car where the delayed warmup reduces fuel atomization, and increases cylinder wash down - really accelerating wear and diluting oil.

I’ve read all the anecdotal stuff of “my engine is fine”. You may think so but the reality is you are only looking at a tiny snapshot in time of the engine life and wear. As a hobbyist, you likely won’t ever have the opportunity to compare engine life of engine A that ran properly vs engine B that has the flaps disabled.

And I’ll concede that because a hobby car only gets driven infrequently - that partially negates the wear argument(s).

But let’s not keep propagating the shade tree mindset that the thermostat & flaps aren’t necessary for proper operation and longevity of T4 engines.

Once he’s in there deep enough to identify the cause, it should be fixed properly not jury rigged.

[Jack Standz]

Thermostats were left off 914s and type iv motors for probably lots of reasons that included lack of understanding about what the T-stat's purpose was, how to install it, etc. Not to mention that many T-stats failed and people didn't recognize that it had failed. Added to that was the fact that you couldn't find a replacement T-stat.

Then along came Awesome Powdercoat with new T-stats that had been unavailable for years. (IMG:style_emoticons/default/aktion035.gif)

Problem is the ones from VW of Mexico T-stats fail UNSAFE and will likely overheat/destroy your motor when they fail (IMG:style_emoticons/default/sad.gif). At least the stock ones failed SAFE.

We still have some working stock T-stats in the hoard, but over the years of scouring parts yards, they just don't show up and haven't for lots of years.

So, is it better to have an UNSAFE T-stat, a broken stock one, or none? (IMG:style_emoticons/default/stirthepot.gif)

[Superhawk996]

So, is it better to have an UNSAFE T-stat, a broken stock one, or none? (IMG:style_emoticons/default/stirthepot.gif)

Well, we’ve reached the point in the program where the strawman arguments appear (IMG:style_emoticons/default/stirthepot.gif)

You would be better off adapting the failsafe VW Bug thermostat with its lower opening temperature than nothing.

You would be better off adapting a Corvair thermostat with its different mounting than nothing.

I agree there was a period in time where it was difficult to find a good T4 thermostat. However there has never been a period of time where it was impossible.

If people want to knowingly make the decision to run without a thermostat; I’m not going to try to stop them. My only goal here is to get people to recognize that they are reducing their engine life by doing so.

[JamesM]

So, is it better to have an UNSAFE T-stat, a broken stock one, or none? (IMG:style_emoticons/default/stirthepot.gif)

You would be better off adapting the failsafe VW Bug thermostat with its lower opening temperature than nothing.

Probably want to be very explicit here given this is the internet (IMG:style_emoticons/default/biggrin.gif)

by failsafe Bug thermostat I assume you are referring to the stock German accordion style and not the Mexican style that most people know to avoid (not all people know to avoid them however as we ripped one off a car a couple months ago)


Also posting again for those that don't know they exist...

https://www.awesomepowdercoat.com/porsche-thermostats

[Superhawk996]

by failsafe Bug thermostat I assume you are referring to the stock German accordion style and not the Mexican style that most people know to avoid (not all people know to avoid them however as we ripped one off a car a couple months ago)


Also posting again for those that don't know they exist...

https://www.awesomepowdercoat.com/porsche-thermostats

Yes, thank you. I wouldn’t want anyone using the the Mexican version.

To capitulate to Jack Standz - I would run no thermostat before I’d run the Mexican part . . . Until I could locate a T4 thermostat or any of the other alternative I referred to.

Let’s put this link to the various thermostat operating temps here too.

https://www.awesomepowdercoat.com/vw-thermostats