'Cooling flaps' in top of engine tin, Cable activated? How do these function? Options

[johnnie5]

Just as the title states....
When I was dressing my new motor I noticed these 'reverse' flaps. But have no idea what cable would hook up to the flapper arm, or where it would come from? Or what would activate it?
Someone please enlighten me...

[type47]

the flaps are "cooling" flaps that divert air over the cylinder heads for .... well..... cooling. (IMG:style_emoticons/default/biggrin.gif) the flaps are spring "loaded" such that if the arrangement fails, then the flaps are in a default cooling mode for safety sake. the flaps are operated by a cable that runs vertically upward beside the engine up through a small hole in the tin. there is a place for a screw and nut to clamp the cable on the rod (the spring loaded rod that the flaps are attached to). the cable is attached to a bellows like piece located under the engine that is the thermostat. when the thermostat gets warm, the bellows expands and the cable is .... relaxed (?).... and the flaps move to the warm engine cooling position. when the thermostat gets cold, it contracts and pulls the cable to open the cooling flaps to the cold engine position.

where is Dave Darling when you need something explained? (IMG:style_emoticons/default/rolleyes.gif) (IMG:style_emoticons/default/laugh.gif)

[johnnie5]

Ok, so its thermostat activated - that makes sense. Where is the stat? Does anyone have a pic?

[blitZ]

Ok, so its thermostat activated - that makes sense. Where is the stat? Does anyone have a pic?

The bellows thermostat is on the drivers side bottom of the engine sump. It's not uncommon for them to be missing and the flaps secured in the cooling position.

[ericread]

Here's some classic pictures:

This picture has the cooling flaps closed - for cold weather.


This picture shows the cooling flaps open - engine warm condition.


This is a picture of the thermostat, which fits near your alternator. It expands and contracts per the temperature. The attaching wire moves with the expansion and contraction, which opens and closes the flaps.


Eric

[SirAndy]

This is a picture of the thermostat, which fits near your alternator.

Just FYI, the bolt for the thermostat bracket is a *through* bolt!

If removed from the case and not plugged, you will have a nice big oil leak ...
(IMG:style_emoticons/default/shades.gif) Andy

[maf914]

A key feature of the spring loaded cooling flaps is that when the thermostat heats up the bellows expands and relaxes the cable which is connected to the flaps. The engine is now warm and it allows the flaps to go to their default position. This position directs the maximum amount of air through the oil cooler for maximum engine cooling.

Should the cable break or not be installed the spring loaded flaps will go to this position. In warm climate areas some people leave off the thermostat and cable and run the flaps in the default position for max cooling.

When the cable is drawn tight by the cold thermostat it pulls the spring loaded flaps into a position that allows most of the air to bypass the oil cooler and travel primarily to the cylinders. If the flaps are not present the result will be similar, limited flow through the oil cooler.

[johnnie5]

Thanks everyone, for the fine explanations and pics! I now have a good understanding of how the flaps work. Being that I live in San Diego, it seems that I will be fine with not re-installing the cable from the stat and just leaving the flaps in the default position.

[ericread]

Thanks everyone, for the fine explanations and pics! I now have a good understanding of how the flaps work. Being that I live in San Diego, it seems that I will be fine with not re-installing the cable from the stat and just leaving the flaps in the default position.

(IMG:style_emoticons/default/agree.gif)

I have the flaps but no thermostat and I have no heating issues whatsoever. Don't you just love living in South Cali???

(IMG:style_emoticons/default/shades.gif)

[Joe Ricard]

The thermostat controls the warming up of the engine.
As in the engine will come up to temp lots quicker. which is what you want , so the cylinder and piston will have less blow by. Happens when things are cold.

THAT IS WHAT THE THERMOSTAT DOES.

[Keoni914]

Interesting information for us newbies! Thanks

One question please, does one need to move the position of the connection point for the wire, completely forward on the flap connection thingie. I didn't know the flaps are positioned in the default cooling position.

Does it make sense to connect the wire while the flaps are closed? (ie tension on the thermostat wire.)

Thanks

What a great forum!!

Keoni914

[rjames]

My cable is fraying from where it is rubbing on the engine tin. I'm guessing that there is supposed to be some kind of sleeve to keep this from happening?

And are new cables available, or can I just use a modified brake cable from a bike or something?

[type47]

One question please, does one need to move the position of the connection point for the wire, completely forward on the flap connection thingie. I didn't know the flaps are positioned in the default cooling position.

Does it make sense to connect the wire while the flaps are closed? (ie tension on the thermostat wire.)

The flaps are to be connected so that they are "under tension", that is, the cable is tightened under the holding nut so the shaft is pushed against the spring. You could use a third hand in tightening the nut on the cable. As the engine warms and blows warm then hot air onto the thermostat, it expands and the spring tension on the rod that the flaps are mounted to, moves to the correct position for cooling.

I've read where someone used a bike brake or gear cable for the thermostat cable. In the factory installation, there is a small grommet (basically a rubber disk with a hole) where the cable goes through the tin.

[StratPlayer]

Pic of thermostat and pulley cable sits in. You can get new cables from AA.

[StratPlayer]

gdss

[mtndawg]

This is where it goes through the tin. You can also see the rubber grommet.

[VaccaRabite]

Keep in mind - while the flaps are supposed to fail open (cooling state) they don't always. Mine failed closed (warming state).

While I fixed that problem (more pressure on the spring, and grease in the plastic bushings) I also decided to remove the T-stat and jsut always have the flaps open.

Its a summer toy, so I consider this a really minor sin.

Zach

[RiqueMar]

Keep in mind - while the flaps are supposed to fail open (cooling state) they don't always. Mine failed closed (warming state).

While I fixed that problem (more pressure on the spring, and grease in the plastic bushings) I also decided to remove the T-stat and jsut always have the flaps open.

Its a summer toy, so I consider this a really minor sin.

Zach

Sorry to re-activate a possibly dead thread, btu being in San Diego and building my 2.0L for a daily driver, would I benefit from having the flaps always open?

[7275914911]

not meaning to (IMG:style_emoticons/default/hijacked.gif) but

If you run them OPEN what would the consequences be of not running them at all??

(IMG:style_emoticons/default/stirthepot.gif) Inquiring minds want to know??

KP

[Jacob]

Are these thermostats still available?