Well, to make a long story short, I gave up on trying to retune this quadrajet so that it ran right after buying the car. It was just too covered in crud. So it's rebuilt now, and I'm fairly certain everything's as it should be inside, and I'm not entirely done adjusting the poor thing due to lack of a tool or two that are waiting for NAPA to open tomorrow.. anyway.

Idle mixture: 5 turns out
Choke: flap appears to snap closed correctly, not alot of tension on it (80 degree day)
Lean Mix Stop: bottom
Rich Mix Stop: 1/4-1/2 turn out
Idle Air Bleed: Unknown

When cranking, it spends about 3-5 seconds under starter power, starts to spin up under its own power for about 1 second, and then returns to starter power. I'm thinking lean, but I've always avoided carburetors like mystical voodoo plague rats, and my carburetor diagnostics skills could easily be surpassed by a birthing moose. I'm doubting the lean mix stop screw would prevent it from at least trying to idle, if not horribly.. accelerator pump makes little to no difference in the matter.. nothing changes with the MCS disconnected (figure with it disconnected it should be full rich.. still doesn't help)

It was sprayed with gumout, soaked in berryman's, and sprayed with gumout again (eww)... I doubt highly that any blockages remain in the passages or jets... so.. any ideas?

 

More info. Idle mixture screws between 5 and bottom, no start. Disabled choke, things got better ... perhaps the rich mixture stop screw needs some serious work.. looks like I'll be waiting on the tool till thursday though.

If all else fails, I've got a friend who can blueprint a q-jet in 20 minutes that I guess I can toss this at. Just happened that he called today asking to borrow an air compressor, so labor trade looks like a good possibility. I'd still like to get it running on my own, though, so, any ideas..

Also, the choke intermediate shaft seal appears to be leaking a little fuel.. Not so concerned about the seal itself, but I am concerned about the fuel level being high enough to do that.. should it be? Guess an external float gauge is on the tool purchase list too.

 

Nevermind.. the car just toasted 3 ECU fuses in a row. The resulting lack of timing and dead MCS easily sum up a no-start, so I'll get that figured out before I go anywhere else with this. (An electrical problem!! *This* I can handle!)

 

And it's handled. MCS is clicking away happily again. Still no start. *sigh*

 

As the moderator babbles on to himself... I wish I could help... I'm trying to learn carbs myself.

Actually, can you tell if the choke opens a bit when the engine spins once on its own? Not sure why it would actually prevent the engine from starting, but who knows..

 

Yeah.. if the dashpot weren't pulling the choke off, it would be a problem.. nor have I tested this as the dashpot worked fine 2 weeks ago when I tore everything down.. besides, at present the choke has no positive effect on the situation currently. I'm adjusting the choke coil from full off to full on in ~2-5 degree increments every time I change something major, and its effect is negligible.

I think I need to start checking for spark today.. there's gotta be more to this than the carb.

 

Usually is.

 

plugs were gas/oil/carbon fouled in varying combinations per cylinder. fired right up with a little help from the accelerator pump on new plugs. thanks folks