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So I rebuilt the 928S..... There were two sets of metering rods I had with it, both the same length and diameter, but one had notches. I used the ones that were already inside the 928s... Now the car idles fine once warm, but it just falls on its face when I go to take off. Could this be related to wrong metering rods? Does anyone know the part number of the correct ones for the 928s? There are different numbers on each set.

Just FYI. Believe you're working on a 52. If so, download the SC containing the specs.https://www.packardinfo.com/xoops/html/downloads/SC/SC-VOL25NO13.pdf Under the chassis designation for your car and in this case, Fuel category you will find most all the info for the carb including the rod numbers and jet sizes. Those are standard specs however there might have been options or different items available for a particular model. Most all specs on any standard item can be found using the SCs.

If a different year, go to the 51-4 service index and under specifications you will find a link to the SC containing mechanical specifications for the year needed.

Standard metering rods for the 928S carb are number 75-767

One size lean 75-814

Two sizes lean 75-815

Sounds like you may have a problem with the accelerator pump.
There should be a small ball and retaining ring in the bottom of the plunger cylinder which acts as an inlet check valve.
There is also a check valve for the discharge jet cluster which looks similar to the float needle. This should be installed with the point facing down.

Thanks so much for the quick reply!!! I'll check to numbers when i get home. One set was definitely 75-767, the other set was 75-7something... Definitely did also start with 7 tho.

I didn't notice a check valve in the accelerator pump... Is it something that would've stayed in the body when I disassembled it?

The other brass check valve is there for sure. It's the little carrot looking one, correct? Point is definitely facing down as it should. The pump pumps good, that was the first thing I checked for... My shop teacher says it could be that it need to be choked longer since it's so cold out lately. Could it be as simple as that?

Did you make the metering rod adjustment?

What is the metering rod adjustment? And the rods on the bench are 75-734, which means the 75-767 are in the carb.

Quote:

See the Fuel & Exhaust section of the 1951 to 1954 Service Manual on this site.

fory, more than just cleaning and replacing gaskets, part of the rebuilding process is to make the necessary adjustments like the float level and the metering rods. Adjustment procedures are found in many sources and are simple. The metering rods are either stepped or tapered and move up and down under varying engine conditions to change the effective size of the high speed jet, and thus the fuel mixture. I don't recall your particular carb at the moment, but there may also be adjustments for the antipercolator valve(s) and accelerator pump stroke - just read thru the manual, or an older Motors Manual which covers this carb in considerable detail.