Blanking off the heater pipes to increase cooling?

[HotVWheels]

Summer in South Africa, daytime temperatures easily into the mid 30s (Celcius) - no heater neccesary! I want to blank off the heater pipe outlets on the fan housing of my '71 Bay's 1600 engine to maximise the cooling air over the cylinder heads. Is this advisable?

 

[Araon]

That should be fine its common for us in good old wet icy cold Blighty to do it, it will as you recon divert more air over the cooler....

 

[HotVWheels]

That should be fine its common for us in good old wet icy cold Blighty to do it, it will as you recon divert more air over the cooler....

That almost sounds like an oximoron? :wink: But that's the spirit: freezing to death in the cabin of your Bay, but with the engine happy!

 

[HotVWheels]

Got an interesting reply on TheSamba on the topic:

It sure is, b/c if you don't blank them off, the air in your engine compartment will just be circulating within itself, if you take the fresh air pipes off your doghouse, install plugs in them, the air will come from your vents, on the side of the bus, & exit via the exhaust vent on the rear underneath the engine.

I don' t know how much difference it would make if everything in the heater system is in good shape. The flapper valve blocks off all the air on the outlet end of the exchangers when it is in the close position, so virtually all of the air goes to cooling the engine. Of course if you have a badly leaking system then blocking everything off might be a good idea.

Actually, the heater valves make sure that air is flowing through the heat exchangers at all times. When the heat is in the "off" position, the heater valves dump the unwanted air under the car. VW uses the heat exchangers to cool the exhaust pipes whenever the engine is running. This helps draw heat off the heads at the exhaust ports.

Best that you keep the fresh air hoses intact, sending cooling air through the exchangers. Blocking off the outlets will increase the turbulence inside the fan housing which does not help cooling. The factory pulled off a pretty decent cooling system. You can do your part by making sure everything is in its place, all grommets and flaps and compartment seal and fail-safe springs, making sure that the engine is clean, particularly the fins through the cylinder heads and the oil cooler on the pre-doghouse Type 1 engines.

VW had a long and glorious relationship with South Africa and Australia, these engines are perfectly capable of handling the heat when well tuned and clean and complete.
Colin

 

[Guest]

Summer in South Africa, daytime temperatures easily into the mid 30s (Celcius) - no heater neccesary! I want to blank off the heater pipe outlets on the fan housing of my '71 Bay's 1600 engine to maximise the cooling air over the cylinder heads. Is this advisable?

:lol: your just rubbing it in

 

[-tipi-]

Yep, there are separate channels for heating inside the fan housing so blocking them won't increase engine cooling. But may make heat exhangers run hotter, which may end up your heads run hotter -> damage.

If you're having trouble with engine running hot, and it's mechanically OK and carbs adjusted well (maybe a very little bit to rich side). I'd make sure that all engine bay seals are ok and all original tin are in place, that no hot air from underneath will by able to sucked to cooling.

If stil not ok, then I'd consider adding oil capacity gradually with extra sump, typ4 cooler and finally with full flow with extra cooler.