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Jon,

When you are assembling a Quadrajet with direct visibility of the primary main jets obstructed by the plastic block what trick do you use to to get the primary metering rods to drop into the jets on the first try and to position the air horn gasket under the metering rod "T" after the piston and metering rods are in ?

Ray - not sure what Q-Jet you are working on. I stopped with the 1974 model year. But all of them up through 1974 put the block in AFTER the metering rods.

The gasket is no problem because of the slots. If yours are not slotted, you maybe have offshore parts?

Jon.

The rookie mistake most amateur wrench jockeys make with the primary metering rods is trying to install them after putting the small spring that holds them against the side of the main jet bore into place before inserting the metering rods into the jets. Get the rods into the jets, THEN install the spring. I learned that in 1966, the second year the carb was in production, at the GM training center in Memphis. I've built several hundred of them since then.
Jerry

"Ray - not sure what Q-Jet you are working on. I stopped with the 1974 model year. But all of them up through 1974 put the block in AFTER the metering rods.

The gasket is no problem because of the slots. If yours are not slotted, you maybe have offshore parts?"

Thanks Jon. This Q-Jet is the OEM item on a 1978 El Camino SS with a factory 350 engine and manual transmission. I actually have 2 of them (Q-Jets), one to run well with and one to pass a smog check. I resorted to that because I found that I can change carburetors for a smog check way faster than I can change the jets and rods and them put back the ones that work well after the smog check. The irony of this is that when I bought the El Camino from an old buddy in 1997 I did a lot of trial and error rejetting until finally settling on main jets and primary and secondary metering rods and secondary metering rod hangers that the engine seemed to really like. That process was time consuming but didn't seem particularly difficult back then.

This carb has a block that has to go in before the primary metering rods, unlike the photos in Doug Roe's book. In getting the El Camino ready for sale I was into the rejetted carb yesterday and had a heck of a time getting the primary rods back into the jet holes. Apparently nothing has changed except the passage of 21 years and very much diminished hand-eye coordination that makes a formerly simple job a little more challenging.

The air horn gasket is slotted and was undamaged by a pretty severe bend required to seat it under the metering rod "T". I have learned that applying grease to paper gaskets that will see multiple assembly/disassembly cycles allows the gasket to release cleanly without damage and remain flexible. The grease was particularly helpful on motorcycle jug base gaskets during my off road motorcycle racing days; no trouble lifting the jugs off the center cases and no gasket residue to scrape off. Obviously those base gaskets were not reused like carb gaskets during rejetting.

I find the Q-Jet more complicated and time consuming to work with than Thermoquads and AFBs and Edelbrock AFB clones. You can probably do them all with your eyes closed.

Ray - I don't know about with eyes closed, but to prove a point, I once changed metering rods in an AFB with the engine running.

Not the e-clones, which are forever banned from my shop.

The throttle springs are much easier to install on Pontiac Q-Jets than Chevrolet Q-Jets.

Jon.

"Ray - I don't know about with eyes closed, but to prove a point, I once changed metering rods in an AFB with the engine running."

Wow, I'm impressed.

"Not the e-clones, which are forever banned from my shop."

Can you explain why that is Jon? I have an Edelbrock 1405 with an electric choke added and jets and rods changed to ones the sbc 350 engine in my roadster likes. This roadster is an old man (73) driven street rod that isn't used for any racing or showing off. Do the E-clones misbehave in some way I'm not noticing?

Maybe not initially.

If you like them, go for it.

I have stated my professional opinion, never in my shop.

Jon.