cooling air flap

[ruddyboys]

Putting the tin back on. If the left hand cooling air flap (the on that connects to the thermostat) supposed to up or down when engine is cold.

[Kevin Powers]

the connection point (where the wire from the therm connects) should be down. as the therm gets warm the wire distance lengthens.

kevin

[retro74]

Here is how it should work:

The thermostat bellows starts out cold. The wire leaving the thermostat goes forward towards the pulley and then up into the tin. I sished mine through with a coat hanger and some electrical tape. The flaps at the top of the tin have a screw that holds the cable. If the cable breaks, then the flaps spring open to cool the motor. Therefore, you must close the flaps while pulling the cable tight. It is a bit of a wrestling move to hold the spring loaded flaps closed while you tighten the cable retaining nut. Just use a long thin screwdriver and have the appropriate wrench to tightrn the nut. If you are using a new cable, then it will stretch and need to be retightened after a week or so.

After you install it, turn on the car and check underneath for the bellows to expand and release tension on the cable. The springs in the flaps will take-up the cable as it moves and that will allow the cool air from the fan to circulate through the tin.

The bellows is important for faster warmups (even in california and Texas and Arizona) since warm oil flows to all of the nooks and crannies in the engine. Aslo, the oil cooler is cooled by the air blowing through the tin and thus open flaps would slow the oil warming process by even more time.

good luck.

Joe C.

[maf 914]

I have my engine out and have been studying the air flap design and movement. What a wierd but neat system! I wonder how someone came up with the flapper linkage as the flaps on the left and right actually move in opposite directions relative to each other. What is obvious though is that the primary difference between cold and hot operation is the position of the oil cooler flap. When cold this flap opens to allow cooling air to bypass the cooler and move on to the cylinders. When hot this flap closes to direct air thru the cooler. The total volume of cooling air flow remains the same, whether hot or cold. It is just the volume that is directed thru the cooler that changes. When you watch the flap operation it becomes obvious why you do not want to run without them, as very little air will pass thru the cooler.

If you run without the thermostat, but with the flaps, you will have slower warmup since the flaps in the fail-safe position directs max volume thru the cooler. If you run without the flaps you will risk overheating since the air will bypass the cooler.

Mike

[HMeeder]

In case you want to know what the shebang looks like, hidden inder the tin, check this thread: Pics of how Cooling flaps work?