Riser tube in intake.

[Curtis Dover]

Hey Guys,

I found this today. Can this be fixed or should I not worry about it. I’m staying with the original carburetor.

Will it affect the way the car runs if not fixed? Got any idea where to get a new tube assume the machine shop can install a new one.  Just a thought, could JBWeld work?

thanks 

Curt

[Kurt]

That is the choke tube. The carb automatic choke pulls air through that tube which is heated by hot exhaust gas. The warm air causes the choke to open. That broken tube will allow exhaust gas to be drawn into the carburetor which will not do anything good. JB Weld will not withstand the hot exhaust gas. You can replace the tube . Here is a discussion in the Help section: https://6364cadillac.ning.com/forum/topics/choke-tube?commentId=654...

[Russ Austin]

That choke tube being cracked will allow hot exh gas will allow hot exh gas to be drawn into the choke assembly and gum it up, AND allow hot exh gas to escape out the bottom hole in the intake.  That has causes carb fires, so it is a dangerous thing to not fix. 

I have the tubes for 15.0 plus shipping. Easy install with instructions.   Please send me an email; [e-mail] 

[Tony and Ginny 429]

Be sure your fuel lines are sound —as gas and the heat from the broken tube can cause a fire 

The temps under hood could be running hotter than normal as that crack is a direct route to the exhaust manifolds HOT exhaust gasses and is leaking those gases now 

The crack will often cause the location to get noisier than normal ( hearing the exhaust valves ) 

The heat is warming the intake manifold to some degree ( pun intended ) which will cause the engine to possibly ——be running  a bit leaner and thus  hotter than normal 

Never really cared for the choke design with the heat tube on my 429 engine myself 

Had the butterfly open and disconnected a lot of my ownership 

When to an Edelbrock 1406 with an electric choke when the time was right but the intake needs to be removed to be blocking both sides of the heat tubes opening  when doing that 

Enjoy 

[C. Van Tune]

If we think that Cadillac method is bad, you should check out what Ford did on many of their early '60s cars:  

The hot side of the heater hose was routed into a special carburetor plate that channeled the water, to help the carb warm up.

The problems, obviously, are that it takes longer to heat the carb/choke this way (versus the exhaust heating the choke tube on our cars) and it presents another point for a potential water leak. 

The car companies were still learning stuff in those days. I guess they still do. 

[rich bewick]

My neighbor is Chips Caddy... he gave me one of these the other day.
He warned when the exhaust leaks into the intake valley area it can/has cause a fire.
Replacement tube is stainless and comes with instructions.

https://www.ebay.com/itm/201888095420?hash=item2f0177dcbc:g:vCQAAOS...