Holley carburetor primary metering block stamping

[Donald H.]

I recent purchased a period/date correct list 3367 for my 1966 350HP car. I am planning to have it restored. The only issue is that it has a later service replacement primary metering block on it. The block has the 4743 stamping as it should, but it is also stamped 3810 below the 4743. As I understand the original would only have the 4743 stamp.

I have found someone who has another 4743 stamped block for sale. I don't even know enough about Holleys or carburetors in general to be dangerous, so what questions should I ask before I decided whether to purchase it or not.

The most obvious one to me is why was it removed from a carburetor in the first place?
Is there anything else that could be wrong with a primary metering block that would make it unusable at all? I assume it could be warped for something like that.

Thanks,

Don

[William C.]

Re: Holley carburetor primary metering block stamping

Some lame-brain stripped the threads for the jets or power valve for one possibility...

[Donald H.]

Re: Holley carburetor primary metering block stamping

Some lame-brain stripped the threads for the jets or power valve for one possibility...

Thanks Bill,

Does that make the block unusable, or can it be repaired like with a Helicoil?

[Timothy B.]

Re: Holley carburetor primary metering block stamping

Donald,

To add to what Bill said someone may also have gotten carried away with a small drill bit enlarging different metering restrictions. These restrictions consist of the idle feed restriction (idle gas jet), power valve channel restriction (enrichment gas jet), and the emulsion bleeds which control the fuel curve.

It's not hard to repair but depends on what you are paying for the metering block. The biggest thing I would be concerned about is the block being flat.

[Donald H.]

Re: Holley carburetor primary metering block stamping

Thanks, I'll make sure the guy will take it back if I decide to get it.