[C1] Heat riser issue
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Joined: Dec 2025
Posts: 9
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From: Oregon
Racer
Joined: Nov 2000
Posts: 349
Likes: 8
From: Hamilton Square,NJ ; Mercer
I didn't read everyone's responses, but I would buy a spacer and dump that thing! I has similar problems with a '63 and nothing but a headache. If that locks up at idle in traffic on a hot summer day, you're in trouble.
Team Owner
Joined: Jul 2006
Posts: 22,202
Likes: 4,187
From: Kannapolis NC
Then the exhaust manifold is not getting hot enough to overcome the tension of the spring, or it's binding only when it's hot, or the spring is no longer unwinding as temp goes up as it should. A surefire fix would be to replace the heat riser with the spacer available. You could try adding more weight to the weighted end of the lever, but might be more trouble than it's worth.
Race Director
Joined: Apr 2005
Posts: 11,287
Likes: 2,147
From: Bowling Green, Kentucky
I remember some of the service replacements and reproductions were binding up in service. You would have to search for this to find all the problems/issues, but they were there. Probably 15 years or so ago. So I would either:
1. Replace with a spacer or just remove the flap entirely
2. Seek out and buy a used original or very early GM NOS
Personally I would just go with Option 1.
FWIW. Larry
1. Replace with a spacer or just remove the flap entirely
2. Seek out and buy a used original or very early GM NOS
Personally I would just go with Option 1.
FWIW. Larry
Le Mans Master
Joined: Feb 2004
Posts: 7,368
Likes: 875
From: Norcal CA
2018 C1 of Year Finalist
I remember some of the service replacements and reproductions were binding up in service. You would have to search for this to find all the problems/issues, but they were there. Probably 15 years or so ago. So I would either:
1. Replace with a spacer or just remove the flap entirely
2. Seek out and buy a used original or very early GM NOS
Personally I would just go with Option 1.
FWIW. Larry
1. Replace with a spacer or just remove the flap entirely
2. Seek out and buy a used original or very early GM NOS
Personally I would just go with Option 1.
FWIW. Larry
