Hello everyone. I have a 1955 Customline 272 with 3 speed. It has been sitting in the garage for a while. So I need some advice.

I had the Edelbrock 573 Manifold refinished and carbs rebuilt. I installed the assembly and she fired right up. I then noticed a slight tap coming from the manifold. Exhaust is coming from the small hole on the left side next to the middle carb. It looks like it should be there but for the life of me I can't figure out what is supposed to connect to it. Any advice on how I should plug it or what should be connected?

 

Anthony, Drums, PA

1955 Customline 272ci.

 

Seems to be on the wrong side but I would say its for a heat tube to the choke. I don't see any reason not to plug it. Chuck

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

I have the exhaust crossover plugged at the head (not using exhaust heat), when my BT manifold was at the machinist for modification he turned some brass stock to dimension of hole and flush fit it, looks like it was born there, it's snug fit so as not to eject, and can be removed without damage if ever needed. 

Ted, Redding, CA

Thanks Chuck and Ted! I will try to come up with something to plug it or see if I can hook it back up to the choke.

Anthony

Anthony, Drums, PA

1955 Customline 272ci.

 

What you are feeling is exhaust which means the carburetor choke coil passage within the bottom of the manifold has been compromised.  The hole in question will need to be plugged or the exhaust crossover passage blocked.  If plugging the hole, then the hole on the bottom on the opposite side of the intake will likely also need plugging.

 

That hole and another one on the opposite side of the intake (which is likely on the bottom where you cannot see it) is suppose to be a simple passage going though the exhaust crossover but sealed to allow a vacuum source to pull heated air through the passage so the heat coil for an automatic choke can function properly.  Because that passage way is leaking exhaust, either the intake casting or the pipe that goes through the exhaust crossover section is broken. 

 

Two options at this point.  Brokengate’s (Ted) suggestion of blocking the heat riser passage at the intake gasket is one.  The other is plugging both ends of that holed passage at the intake.  While you might get away with simply putting a threaded plug in the hole that’s leaking, I suspect you’ll find the exhaust still leaking at the other hole on the bottom of the intake.  That one will require the intake to be removed.

Lorena, Texas (South of Waco)

Ted,

First off thank you so much. Now, If I understand this correctly I can block the exhaust crossover with no adverse effect on the engine? This crossover is there to heat the tube (which appears to have broken) and would not be needed for any other purpose? I am assuming a small metal plate and gasket sealer would be sufficient?

Thanks,

Anthony

Anthony, Drums, PA

1955 Customline 272ci.

 

Depending on where you live you may have cold/cooler weather driveability problem. Part of the reason for the exhaust crossover passage is to warm up the carb for better cold weather performance. If you dont want to plug off the crossover completely you can install the intake gaskets with the crossover port that has the restriction already there. Some guys use these to keep the paint from burning off the manifold too soon. If you go the homemade restriction route, make sure you use a thick enough metal to last awhile & not burn through. Dont ask me how I know.

Dan      Kingman Az.      86409

It may make you feel better- if you are running original 94s they are much more prone to boiling and leaking down after shut down- especially with the ethanol laden gas now. Even without the issue you have I found it beneficial to put a block off on the heat riser. In sub freezing it requires a little longer on the choke for warm up, but no adverse effects.

I cut a small tab of aluminum and slid it between the gasket and the manifold with no issues.

Mike Rizzo

1963 F100 "Rudy"

Daniel Island, SC

Randy, Eventually you'll want to replace the aluminum with steel (sheet metal). If you drive the truck much it will burn right through the Aluminum. Actually it'll burn through the steel too, just takes longer!

Frank/Rebop

Bristol, In ( by Elkhart) 

Frank and Mike,

Thanks so much!

I'll keep you guys posted!!

Anthony, Drums, PA

1955 Customline 272ci.