Cold Weather Flap on the Engine Door

[AustHaflinger]

A couple of years ago I fitted a engine watchdog system so I can monitor the temperature of the engine. I have the sensor mounted to one of the head bolts so I get a readout of the metal temperature of the engine.

Having run it for a while now I have learnt that the engine runs about 75c in warmer weather and about 70c when cooler and that at lower engine revs the engine is hotter and at higher revs it is cooler - as a direct result of increased airflow due to increased fan speed at higher revs.

Prior to fitting the Watch dog I never really thought about engine temp but recently with winter here I have noticed engine temps are quite a bit lower than usual - so I decided to close the flap on the engine door so that only half the air vent is open - brought the engine temp back up to "normal" and that is with outside temps only 1 to 4c - it has been a warm winter though snow is forecast for this week.

So anyone else use the cold weather flap and do you think it makes a difference to the operation of your engine in cold weather - I have never used it before even when I have been up in the snow with outside temps about -5c.

Garry

PS - still being blocked by SpamHaus

[heinkeljb]

Can't say I have noticed any difference in the way Lurch drives when I have closed the cold weather flap. Only really did that to try and get hotter air in to the cabin when I was running the Hot air heat exchanger heating system.
I don't know what sort of tempreatures you are supposed to use it at. Don't remember reading about it in any of the workshop manual or handbook I have.
There again, we don't get very cold weather here in the south of England with temperatures in the minus number for any length ot time.

Both Internet Provider and hosting company blame others so I am still looking for a solution.

John

[AustHaflinger]

Hi John - I never noticed any issues but the Watch Dog gives a precise readout of what temps are doing on the engine. I soon learnt that coasting down a steep hill with no load and low revs, the engine gets much hotter than driving up the hill in lower gears and revs up high - the opposite to what you would think - is due to increased airflow from the fan when revs are high.

When the engine is stopped after a run, temperatures go off the chart - at least greater than 120c but drops really quick once the engine is started.

Just shows how important the fan is to keep the engine cool in various outside temperatures.

I lived in Hampshire for a year a long time ago and the temperatures except for high summer are very similar to what we have here in Canberra (pleasant 16c outside at the moment but was -4 overnight) so I was interested to note the engine running a bit cooler in really cold weather - the closed flap brings temps up a bit but would be unwise to leave closed in anything but really cold weather. I also looked at the handbook under winter driving and it does not give a temp but also indicates the little flap on the cooling system air exhaust should also be closed - I have not closed that.

Cheers

Garry

PS - yes is still being blocked by Spam Haus is only on this site no where else - now up to 10 submits before a post goes through. I dont think there is much that can be done and while an inconvenience is not a show stopper just yet.