The heat tube in my B manifold has corroded out, and the mushroom breather has exhaust staining around it on the manifold. How do i remove these?

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South Australia

Two ways to go that I'm aware of, Slick.

1) I have an acquaintance who drills out the old tube by coming at it from each side of the manifold. NOTE: the drill size is different for the two ends of the tube!

2) Being paranoid about the drill bits tracking correctly, I took a piece of 3/8 inch diameter cold rolled steel round stock and turned it down on a lathe to the appropriate diameter for one end of the replacement tube inside and outside diameter. This amounts to being a driver for tube removal.

With the driver, to date, I've only needed to drive on one end of the tube to accomplish removal of the intake manifold choke heat tubes. For a reason I can't remember, my driver was made to fit the mushroom end of the heat tube. -Perhaps fear of breakage of the cast iron intake manifold exhaust bypass section that mates with the cylinder head on the choke housing side?

The driver end of the 3/8 inch rod was turned to a dimensions of .269 for the smaller diameter x 1/2 inch in length, and .342 for the larger diameter x 3/4 inch in length. I doubt that the smaller I.D. was critical other than being smaller than the actual I.D. of the tube to permit inward crush of the tube as needed when being driven.

These dimensions have worked for removal of FoMoCo B6A-9890-A heat tubes. I have yet to remove the heat tubes on a '57 Ford dual quad manifold. I know that the heat tubes are different in length than the single quad units...

Hope this helps.





NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

I failed to notice my "B" intakes heat tube was corroded out, when I bought it. Fortunately the intakes price was lower than often asked. It was difficult to remove. As I recall, I found a drill bit or bits about the same diameter & drilled it partly out. It was a bitch to drill! Then I used a suitable flat end punch to knock the pieces loose. The only replacement I was able to locate was on line & they were a pair & the asking was very expensive. So, I passed & made up a tube using a suitable diameter copper tubing. One end is partly closed up & the choke feed end is extended out & requires 90* fittings. I applied exhaust pipe seal on the ends as they were installed, to hopefully avoid leaks. However, the intake currently isn't on the car, so I don't know if this setup will work properly?..

Paul

To follow-up on what Paul was saying...

CASCO in Coshocton, Ohio is one source for intake manifold choke heat tubes. What catches my eye in looking at their offering is that instead of being mere carbon steel (as original) they have a stainless steel reproduction part. I'm sure that other suppliers have the same piece, but I've been dealing with the Browns' for years.

CASCO's part number for the 56/57 intake manifold choke heat tube is 9890. Price in their 2013 catalog is $19.95
24 hour ordering @ www.classictbird.com

Hope this helps!

NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Does the mushroom breather just pull off?

The stainless heat tube would be the way to go, but i think i will just plug the holes,
choke is stuffed from the exhaust gases getting in, and it rarely gets too cold here in South Oz.

Thanks, Al.


South Australia

The 'mushroom' is entirely thin gauge sheet metal in construction. The underside of the mushroom and 'stalk' are one piece with the cap 'edge' wrapped over same. The 'stalk' that is wedged into the heat tube is hollow, tubular, 1/2 inch long section. The 'stalk' tube has a 3/8 inch slit opening from its end extending toward the underside of the mushroom cap. The mushroom 'stalk' is a push-fit into the heat tube opening.

Spray some penetrating lubricant on the stalk at the opening to the heat tube, grip the edge of the mushroom with your fingertips and patiently wiggle the mushroom cap while gently pulling it toward you. This may take a while to work free... The leaking exhaust gases, carbon, and probable corrosion are holding the mushroom from easily coming out.
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IF you were to replace the heat tube, you would have to remove the intake manifold to accomplish the work required.
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IF you are not going to replace the heat tube for the reasons you mentioned, consider disconnecting the tube to the choke stove and blocking the entrance to the heat tube on that side of the intake as well. Presently, if you are seeing carbon around the 'mushroom', realize that the same carbon is traveling into the choke housing where the bimetallic spring is located. Left as is, the bimetallic spring, phenolic choke cover, and metal choke housing will get caked-up with carbon like you will never believe!

Hope this helps.

NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York