[divotandtralee]

I think your premise is a little faulty. I don't have it in front of me but it is VERY unlikely the spring is wrong... I'm going by my best sense ...1) The cotter pin does not belong in the picture.. The Spring has to be loaded by perhaps a half turn of one leg to create tension., then the leg is coaxed into the flap rod hole. It seems a little tricky but it is how these springs work .. much like the spring on your hood or trunk lid prop. It's all a matter of which leg to pick on.. The other has to be anchored in a hole and might be the easier to maneuver. That's the way I see it.. It's almost impossible to think the spring is backward.

Once you see how it works the spring remains stationary with no outside influence.. Semi relaxed when the flap is closed .. just enough to keep it close.. then under tension when the cable is pulled. At least that's what I think is going on here

 

[divotandtralee]

I had an epiphany moment.. I seem to think the way to load the spring is to connect both ends in a relaxed state...Then, I suppose you disconnect the actuation rod from the flapper inside the duct and rotate the rod 180 or 360 degrees which tensions the spring and then reinsert the flapper/rod connection pin, or whatever is in there, that locks the rod and flapper together. Seems like a logical way to do it. There's always a AHA way to these puzzles.

 

[Whiskeydave]

Thanks for the reply Divot! I tried using no cotter and doing as you suggested but this puzzle beat me. I know its impossible to think the spring could be backwards but I'm just going off all the photos of 750/101 heater boxes I could find on Alfabb. If you see below (and believe me I did not monkey with the pictures!), there's no question that the spring is wound "opposite". Regarding the cotter, I know its not good to assume that just because my heater came that way and all the pictures I could find on Alfabb show a cotter, that it originally came with a cotter, but it sure seems to be an OK way to connect it. You are absolutely correct about putting it together in a relaxed state and winding the flap to tension the spring. It just so happens the "direction" of the hook on my wrongly wound spring won't allow tensioning the flap in the correct direction to allow the manual cable to do its job opening the flap against the tension and allowing the tension to pull the flap back closed. At least for me. Believe me I fiddled with the darn thing every which way but Sunday but I'll keep trying. Went to the big hardware store that has about 1000 springs and couldn't find one yet but I won't give up. Even though I know these heaters don't really do much in the cold anyway!

Does anyone out there have an extra spring?

 

[divotandtralee]

I thought I had it but without one in my stash, I'm flyin' blind.