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4 hours ago, 240260280 said:

Wheel bearing race drifts:

1" black iron pipe coupling (ground a tad smaller)

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I wondered why I had a cast iron pipe fitting in my Z parts drawer! You told me about how that reducer would work, and it did. Thanks again. :beer:



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240260280, is your jet alignment tool primarily for the 4 screw dome carbs, or for either the 3 screw of 4 screw?  I can see how it would adjust the nozzle in the 4 screw carb to sit in the appropriate position.  I am trying to understand how it would benefit for the 3 screw, as you would have to take the dome and piston out to put the needle in, which would undo your adjustments.

54 minutes ago, duffman said:

240260280, is your jet alignment tool primarily for the 4 screw dome carbs, or for either the 3 screw of 4 screw?  I can see how it would adjust the nozzle in the 4 screw carb to sit in the appropriate position.  I am trying to understand how it would benefit for the 3 screw, as you would have to take the dome and piston out to put the needle in, which would undo your adjustments.

It is for aligning the nozzle sleeve (that holds the jet) to the centre of the piston. If you disassemble the bottom of the carb, you will find the nozzle sleeve has freedom to be repositioned within the nozzle sleeve set screw:

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This is a pre-oiler I put together yrs ago, I use it for every engine rebuild just before start up or on engines that haven't run in a long time.  The air hose attaches to the nipple I welded on, 2 liters of fresh oil goes in the canister, oil filter on the outlet hose, usually I screw the fitting into where the oil pressure sensor goes. Fill it with 90psi and squeeze the handle, the entire oiling system is filled including the engine oil filter.

 

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8 hours ago, 240260280 said:

It is for aligning the nozzle sleeve (that holds the jet) to the centre of the piston. If you disassemble the bottom of the carb, you will find the nozzle sleeve has freedom to be repositioned within the nozzle sleeve set screw:

I respectfully disagree. That needle/nozzle alignment method will not work on the odd bird 72 3-screw round tops.

The nozzle sleeve is not adjustable on the 3 screw round tops. On those 72 carbs, the nozzle sleeve is pressed into the underside of the carb body and does not come out. Once it is pressed into place, it's fixed. No adjustment:
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So since the nozzle sleeve is hard fixed, they do the needle alignment using the dome up top instead. The three hold down screw holes are intentionally sloppy allowing the dome to be positioned in the correct location. With that in mind, the needle alignment on the 3-screw round tops is set at the factory using the cone shaped alignment nubbies. Cast in place once the domes were aligned with the nozzle position.

The alignment was set at the factory. Once and done and (assuming the original nubbies have not been broken off) nonadjustable after they leave the factory.  I assume they took that power out of the owner's and dealers hands because they felt they weren't doing it right.

Here's a 3-screw nubbie:
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Oh, and all that about dome alignment... Here's my dome / nozzle sleeve alignment tool. Centerless ground precision stock. Sub-thousandth tolerance. Take out the suction piston and put this in it's place:
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So how do you use it on the 3-screw round tops? Well, if you still have alignment nubbies, then you don't need to align anything. It should already be aligned. But if one or both of your alignment nubbies are broken off...

Insert the alignment tool into the carb body and put the dome on:
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And then while the dome is held in "perfect" alignment, you cast the alignment nubbies in place:
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Fill up the hole and then wipe off any excess:
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Then once the nubbies cure, pop the dome off, and presto... New nubbies! :
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The eagle eye might notice that carb is a flat top, but the 3-screws used the exact same alignment technique.

10 hours ago, Captain Obvious said:

I respectfully disagree. That needle/nozzle alignment method will not work on the odd bird 72 3-screw round tops.

 

 

You kids and your late model modern cars!

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