Exhaust manifold heat riser: Did I do this right?

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scott_s

scott_s

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The heat riser wasn't hooked up on my car. It moves freely. I wound the spring as tight as I could and then put the end back over the post. Now it's under tension and springs back into place.
I haven't had a chance to drive it and get it to full operating temp since doing this. Does it look like it's now installed correctly? Is there a possible reason why they may have left it not attached? When NOT attached but still in place, is there a default position? It was just loose and flopping in there....would it have defaulted to open?
 
The hook on the spring should contact the pin cold or hot. Obviously the valve should be closed when cold and open during warm up. One turn too loose and it won't work properly. One turn too tight and it might not open. You need to fiddle with it to get it right.
 
It wasn't hooked up at all! I wound it by hand....pretty much one tight turn, enough to get it on the pin. I marked the weight. Next time I drive it long enough to get it good and hot, I'll see if the mark has moved.
 
Looking good. Just confirm that you haven't wound it too tight. That little coil spring is an anti-rattle spring.
 
It will not hang open when hot. The spring unwinds tension enough to allow the flapper door to open on acceleration easily when warm. It opsne on acceleration when cold too, but it takes much more acceleration to make the flapper open. As @toolmanmike said, it's a kinda balancing act.
 
Murray said:
Looking good. Just confirm that you haven't wound it too tight. That little coil spring is an anti-rattle spring.
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The little spring is loose. I may dig around and see if I have something to replace it, or even cut half a coil off it.
 
scott_s said:
The little spring is loose. I may dig around and see if I have something to replace it, or even cut half a coil off it.
Click to expand...
You could do like I did mine. Just knock the entire valve out and plug the holes, make a block off plate to install between the intake and exhaust manifolds to block the exhaust heat from getting to the intake. You live in South Carolina. Unless you drive in the dead of winter, you'll be fine. Even then if you allow it to warm up good before you drive it. Mine will idle 30 seconds after starting with the choke not hooked up and WIDE open.
 
I live in Hawaii, this will definitely be deleted LOL. Some local guy gave me a block off plate, but it doesn't look like it will sandwich between the manifolds actually.
 
Cruisingram said:
I live in Hawaii, this will definitely be deleted LOL. Some local guy gave me a block off plate, but it doesn't look like it will sandwich between the manifolds actually.
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I made mine out of the same thickness steel that the metal gasket is made from. There's a guy on ebay that sells a BLOCK that's like 3/8" thick. That won't work because it will throw the manifolds way out of alignment. I sprayed it with a thick coat of copper coat and it sealed up fine.
 
RustyRatRod said:
I made mine out of the same thickness steel that the metal gasket is made from. There's a guy on ebay that sells a BLOCK that's like 3/8" thick. That won't work because it will throw the manifolds way out of alignment. I sprayed it with a thick coat of copper coat and it sealed up fine.
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Guy said he got it off ebay-that makes total sense. I will just cut one out of sheet metal.
 
Well, took the car out to dinner tonight. Checked when we got to the restaurant and again when we got home. If anything, the spring got LOOSER as it warmed up and the flapper didn't seem to be doing anything.
Does that mean I need to try and wind it tighter?
 
scott_s said:
Well, took the car out to dinner tonight. Checked when we got to the restaurant and again when we got home. If anything, the spring got LOOSER as it warmed up and the flapper didn't seem to be doing anything.
Does that mean I need to try and wind it tighter?
Click to expand...
That's how it works. It loosens up to allow the valve to open more when it's hot. Was the valve just hanging open?
 
More or less, yes. I put a paint dot on it and it was at the same position, but the flapper was just loose.

EDIT: Just checked now that the engine is cold again and it has tension on it...springs back. So, I guess it is right!
 
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