check those heat risers

John ED Renstrom

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I could tell the 68 was running hot on the intake on the way home. I moved the wire harness out of harms way but it milted the plastic off the kick down switch. yesterday I checked the heat riser and found it was movable but vary stiff and stuck in a mostly closed position. the spring was off the peg and it had fallen over center to shot most of the gas across the intake. it never would have caused you any trouble around town. the car did not run hot in the water jacket but boy was the carb hot. been better is it was 10 below for running it down the interstate. so when it's cold check those heat risers and make sure there free and hooked up.
 
blew that set of pictures forgot to wait till the loaded here they are
 

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I can tell you that the one on my '68 rattles like crazy.....drives me nuts. Have looked everywhere for a new one, but can't find one anywhere. Steinberg says to just take it off, cut out the valve and put it back on.
 
I replaced them...........no check that.........Tim my mechanic replaced the heat riser on my 64 this year. Of course what hasn't Tim replaced on any of my cars this year. I am claiming him and his wife as dependants for 2010.
 
I can tell you that the one on my '68 rattles like crazy.....drives me nuts. Have looked everywhere for a new one, but can't find one anywhere. Steinberg says to just take it off, cut out the valve and put it back on.
Did something similar to the '80 S&S... noisy rattles & deteriorated linkage so I welded it in the fully open position
 
I can tell you that the one on my '68 rattles like crazy.....drives me nuts. Have looked everywhere for a new one, but can't find one anywhere. Steinberg says to just take it off, cut out the valve and put it back on.

that may be what happens to this one. if I can't figure out how to get it back. the tab the rides again the stop got weak and it went all the way around let it fall in a all most closed position.
 
will do. as soon as I get it down off the jack stands. it is a Tony find out of Nebraska if I got the story right. a clean 68 combo with the removable panels.
 

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Been a long time since I had to fool with these things, but would a hand choke conversion be possible here and eliminate the heat riser prob? I still think the manual choke, controlled from the dashboard, was a wonderful device. Doesn't require rocket science to use one, and is just about bullet proof, at least in my experience. Wish I had my '62 Fairlane back. Siiiggghhh........................
 
The choke is in the carburetor, and the heat riser is in the exhaust. I guess that if you were creative, you could hook up a throttle cable to the heat riser and manually operate it... :wowguy:
 
Thanks for this post! My 85 Eureka Pontiac runs great until after a long drive, then it runs rough and is hard to start and keep running, maybe this is my problem. Already had the carb checked out and there is nothing wrong with it.
 
kink down switch

You picture of the kick down swich made me realize that mine is missing on my 68 limo I was wondering what the wires were for now its time to check that out
 
I'm finding stuff on the 68 that no other year has. all the rest have the kick down switch on the foot feed inside. I'm hoping this one still works. the shaft is plastic and it melted the end off. I remade it but who knowes if I got it right, till I can drive the car. I'm hoping I just burnt the gasgets out of the intake. I have a vaccuum leak now and a steady rumble out of the center. but she did carry me home. now I just got to fix her up a little.
 
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