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.

[Superhawk996]

@930cabman

Here’s the thing. The defroster performance has absolutely nothing to do with engine warmup.

The defroster performance is based on the heat exchangers obtaining heat from the engine exhaust heat.

Regardless of the overall engine operating temperature, the exhaust gas exiting the combustion chamber is in excess of 600-800F almost instantaneously.

Just because you have heat doesn’t mean the engine is at operating temperature.

You also keep going back to the analogy of your engine. Engine wear from running cold doesn’t manifest immediately. Unless you have multiple engines that have been run to failure or end of life to compare to a singular data point of your engine at a few thousand miles is practically meaningless.

How many miles on your engine?

I think we both want the same thing for Ron, a functional car to drive.

The thing is for him to disable the flaps, he would still need to drop the engine and resolve what ever is limiting his flap movement and preventing them from getting to full open.