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Stuck heat riser 383

Moparnocar

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67 charger, 383. Just noticed the heat riser is about a quarter of the way closed. any backyard ways to get it unstuck Easley or bust it out of there without removing the manifold? Just not in the mood to do that.

remove the exhaust pipe and it was an air hammer? Anybody ever attempted something without removing the manifold? Thanks
 
GM used to market a product called Carbon X-88, in a "squeeze the sides" can. The can also included a plastic semi flexible 6" long nozzle. Not sure if it was available in aerosol cans. Excellent solvent for stuck heat riser valves and "frozen" exhaust manifold bolts and nuts. You may also want to try an industrial solvent called Butylcellosolve (a liquid) used for de-carbonizing diesel engines. Not sure about the availability of Carbon X-88....it may have been legislatively discontinued....how sad. Just my opinion of course.
BOB RENTON
 
I have a 71 rr with a stuck valve. How can i tell if its stuck open or closed? Its been stuck for years
 
I have a 71 rr with a stuck valve. How can i tell if its stuck open or closed? Its been stuck for years
The position of the riser on the outside, it should move, if not, it's stuck, and probably stuck partially closed
 
How can i tell the position on of the rise? Runs just fine
 
I would drop the exhaust pipe and look up from below. Usually easier to unbolt that pipe than the manifold.
 
Depends what style you have, I have this style, and on one car it's almost in this position (stuck a little closed) my other car, the riser easily moves by hand

If you can't see, and don't want to remove the pipe, I'm sure a non contact thermometer would help to see if it is stuck closed

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Probably have a shop cut it out next year. Summer car. I have the round style counter weight I believe that style started in 71. I think if it was stuck closed I would have drive ability problems.

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50/50 mix of acetone and Marvel Mystery oil. Soak the two ends of the shaft for a few days. Mix up some more and repeat application of the mixture.
The acetone causes the Marvel Mystery oil to wick into the bushing, however, it evaporates quickly so you need to mix up a new batch each day to get maximum value from your concoction.
 
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