Heat Riser Open or Close Direction

Steamer

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My stock exhaust manifold's heat riser/flapper works fine. Had the manifolds blasted, cleaned up, and treated with a coating. And of course I put the manifolds back on and just now putting the bi-metal spring on. I can figure out which way to put the spring, if I just knew what direction opens or closes the valve. Does anyone know off hand which direction it should rotate when warmed up?
I can't believe I did this again. I'd hate to pull the exhaust pipe off to look up in there. Any help appreciated.
 

Steamer

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Well I found this pic of a 2F manifold with 3 studs. My F.5 has two studs but I’m guessing the flapper action/rotation would be the same. The flapper in the pic looks like it is in the, “heat up the intake” position. So, if that’s correct, then looking from the front, a clockwise rotation would close off heat to the intake manifold.

This is all that’s holding up my Sniper first start up. So, I think I’ll go with it. If someone sees it’s wrong, let me know and I’ll change it.

ExhstFlpr 01.jpg
 

bb67tlc

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No idea if my 67 would be the same direction but, don't see why it wouldn't be. This is on the rear of the manifold, and you can see the C for Cold and H for Hot on the bracket that stops the rotation.

ab-engineHeatRiserWeigt-c.jpg
 

Steamer

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Ah hah! That makes sense now. I have it backwards. From the front, it rotates counter-clockwise when it warms up. I'll flip the spring in the morning. Thank you Sir! 🍺
 

Steamer

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This link should illustrate the arrangement for your 1972:

I have a 74 but "Yes" that link with your pics did it. Your pic of the spring in place corrected another mistake I was making. I was believing that the spring un-coiled when heated. I was wrong. It coils up tighter when heated. Just checked with a heat gun.
All clear now. Thank you!
 

Steamer

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I'm on the original spring that came with the new SOR manifold I got in 2000. Fairly rusty but seems to be working. It was fun trying to move a piece of sand cloth around that spiral to clean it up.
I'd be very interested to find a new alternative spring. What do you suggest?
 

73FJ40

After another night of rust removal!
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@Steamer


Things have changed regarding price and vendor since I posted this, but if you do a google search on
Omix-Ada 17625.02
you will find a number of vendors if you click on shopping.
 

Steamer

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"Ordered" Looks like I'll just have to bend the hook on the end. Expected delivery 3-5 days from Amazon. Thank you sir. Never thought I'd have a chance at replacing it.

"EDIT" thought I'd add the pic

Omix-Ada 17625.02.jpg
 
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