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After a thorough (I think) search of the Clipper parts book, a cpl hrs searching here and participating in topics, I'm no closer to solving a mystery. 2103-26, 356 Super Eight engine, left front of the cylinder head. That tube with the 2 legs bolted to the side of the head, what is it? What is it called? What does it do? How important is it? Where's my damn car keys!? Ok, forget the last question if you haven't already. I'm gonna take a stab at it's use/fuction/importance and I have 2 reasonable guesses. 1st guess, it's a form of vibration balancer that by adding a bit of weight to the side of the engine it might cancel that 2nd or 3rd little 'wobble' they detected in testing and came up with an elegantly simple (technically) solution though not aesthetically pleasant to the eye.
2nd guess, there's a sound or a hum at certain speeds due to the locations of the oil fill and air cleaner assembly that creates a whistle or slight whirring sound, the tube being a device to force air through itself and around those things. I have noticed a slight sound under the hood when driving higher speeds into the wind but can't place it as mechanical or air speed in nature. I can't believe it's something as simple as a place to hook a strap for a certain service operation because what about the smaller siblings? Wouldn't they need it too? Thanks in advance, it's just one of those 'things' for me, and also because mine's missing as I seem to suspect many are.

If your talking about the air flow tube. It was put there to direct air in to the oil filler cap. To help circular the gases out of the block. The picture I have attached show where someone had bent it out of the way of the oil filter and now it does no good for directing the air to the oil fill cap.
If this is what your talking about.
Wes

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The tube was one of the steps in a long process Packard went thru to try and prevent valves from sticking when guides rusted in sitting engines. That included varying length oil fill tubes, & different shaped caps to avoid turbulence and a kind of suction effect at road speed from air flowing around the oil filter canister. They finally added the air vent tube. Its purpose was to provide a rudimentary forced ventilation from the fan to feed thru the filler cap into the crankcase in another effort to prevent condensation from forming. It was mostly useful when long periods of idling or slow travel was an issue and normal speed was not able to draw air thru via the regular suction of the crankcase vent. Was only used on the 356 engine. That particular item is discussed in Service Letter Vol 15 #3 of Feb 1, 1941.

That's the one, and it makes good sense too. It only has the roaddraft tube to expell crankcase pressure, or indeed create a depression in there (an excellent condition). Moving air will siphon itself after a short time, the hotter it gets the faster it moves/siphons. Thank you, and I can see, and frankly hear, what it's like without it. My engine has a minor blubber out of the fill tube when it's cold. Almost sounds like a knock but it's bubbly in nature, not at all mechanical. It also vents out of the fill at low/idle speeds once warm too. Now I need to find one to copy (looks easy to make). Drs Watson I presume? Thank you much...

It is not hard to make a reasonable facsimile. I made a modified version when I added an AC compressor on the L side of my 47 engine where Packard moved the compressors on prewar Clippers. I have no idea what Packard did to the tube and oil filter when moving the compressor but I chose to relocate them slightly downward and needed a lower tube to go under the bracket. Without the oil filter in the air path it may not have been necessary but the compressor bracket does block a bit of air so figured it wouldn't hurt to keep the tube.

Finding the 1 5/16 ID of the tube Packard used was difficult. I used one close but not quite the same. Don't remember the size offhand and can't remember if it was a thin wall exhaust tubing from parts store or electrical conduit. Straps were ordinary steel flat bar from the hardware store 1 wide x 1/8 thick.

The legs are 1" wide and 8" long. Approx 1/2" at the end is bent and curved to weld to tube and the remaining length is bent in a couple of places. The main bend is 4" from the end of strap and is approx 30 degrees. A smaller bend is about midway between the tube and main bend with an angle as needed to match the vent slot in the cap. The slot is sized for a 3/8 bolt and is 1" long.

Here are dimensions of the original next to the one I built. Mine has shorter legs, different bend and narrower slot.

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I hope the engineer who came up with this idea to fix the problem, received a raise or at least a bonus.

The picture and dimensions are an awesome aid for this. Very grateful for the help. Some .030 wall 1 3/8 tube will be just right. Tube is O/D, pipe is I/D. 1 3/8 is like snowmobile exhaust tube, and imagine that, I have some from my sled exploits. I'll share the journey folks, thank you again.

Just realized I forgot to include a dimension. The rear strap is positioned about 1/8" from the end of tube and inside to inside distance between them is just over 3 1/4". Since the slots have to fit over the oil filter mounting studs that one probably wouldn't be too hard to figure out but here it is anyway.

I have one extra....free to good home. PM me

In process of rebuilding my 2126. had a spare and prepped them both since I was set up. Both have been wire brushed, treated with Permatex Rust Treatment and then sprayed with SEM self etching primer while the Permatex was still "green". Ready to paint and install. As a side note, I think ( and might be corrected here) that it is important to position the oil cap with slot facing tube to assure air entry is maximized.

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