I need the stock specs for a 17050213.

[Cadman-iac]

  Well, this carburetor runs rich from off-idle to 3500 rpm. It's not the timing.
  I noticed that this one has a  .016" smaller LIAB than the other 3 previous carbs, so is this the whole problem with the other 3, the LIAB's were just too big?

 And how would I get this one to lean out a bit in the off-idle to 1500rpm range? Enlarge the LIAB'S slightly?

 Something else I noticed is that the jet/rod combination in this 17080213 carb, (#72/49M), has a cruise metering area of 2.19 thousands of a square inch, yet runs much richer than two of the other carburetors that have a jet/rod, (#72/44 from Cliff), metering area of 2.55 thousands of a square inch, and the 3rd one has a metering area of 2.52 thousands of a square inch, (#70/41K). What's up with that?
 Does the LIAB's have that much effect on the AFR?

[77cruiser]

Have you tried adjusting the APT on this carb? How's heavy part throttle?

[Cadman-iac]

Have you tried adjusting the APT on this carb? How's heavy part throttle?

 No, not yet, it was just getting dark when I got back from the test drive.  I do need to look at that, I didn't think about it being set too high.  I set it at 3 3/4 turns according to the specs I got from Kenth. I thought it was a bit much right off the bat, I don't usually run it up until I try it set at minimum first. But since I was trying to set this one up exactly like it left the factory I figured I'd try it and see how it works.
 I'll give that a try before I do anything else.
 But if this doesn't change it, would the LIAB's be a possible cause?

 The heavy part throttle is rich as well. I don't remember the reading, I forgot to bring my recorder for notes this time. But it's definitely fat from top to bottom.
 Im actually glad too, I was beginning to think I had some other problems with the engine instead of the carburetion. This just proved it.
 Thanks for the suggestion.

[novadude]

I think the LIAB could definitely be part of the problem with the other carb.  I've found that 0.062 vs 0.078 just seems to work better for off-idle.  As for metering area... I don't think you can compare SMAB carbs with DMAB, as they seem to behave different with regards to main system metering area.

I've shrunk the LIABs with an old accelerator pump ball and a punch, and cleaned up with a drill.  This doesn't always go smooth though, so be careful.

[Cadman-iac]

I think the LIAB could definitely be part of the problem with the other carb.  I've found that 0.062 vs 0.078 just seems to work better for off-idle.  As for metering area... I don't think you can compare SMAB carbs with DMAB, as they seem to behave different with regards to main system metering area.

  Novadude,
 The last carb was a SMAB, #17084226, and it had a larger metering area than this one does.

  I'll start with adjusting the APT, and if it doesn't work I'll make the LIAB's on this 17080213 replaceable with set screws, and try smaller ones until it gets into an acceptable AFR range. Hopefully it doesn't change anything else. The higher RPM mixture can be fixed with the jet/rod combo and the APT setting.

 The difference between these two is definitely confusing, but I'm gonna figure it out, it might take me a while, but I'll get there, (most likely with help from you guys).

[77cruiser]

I dug one up in my stash, it pretty crusty inside must have had water in it.
Maybe I go through it & see what happens.

[Cadman-iac]

  It took me a while, but I've got it pretty close now.  The off-idle mixture is much better, and the high speed mixture is right where it should be.
 I had to increase the size of the LIAB'S to  .072" from  .062", and had to reduce the jet size from #72 to #70, keeping the 49M rods.
 I've still got to dial in the secondary airvalve spring setting, stock is 1 turn, but it works much better at 3/4 turns.  I need to get the secondary mixture right, i think it's gonna need a fatter rod to lean it out at WOT, it's just a bit rich yet.
 I'll post the specs once it's done, both where it was and then where it ended up.
  Thanks for the help in figuring it out.

  Rick
 

[77cruiser]

How does it run? Are ya having fun?

[Cadman-iac]

How does it run? Are ya having fun?

 Weeeeellll, im not sure I'd call it fun, but I am staying busy.

 I think I've got the primary side pretty much dialed in.  Gotta do one more road test to verify that tomorrow. The tip in test I had to do several times to get it to react like Cliff suggests, but its right on the money now. Goes up about 60-70 rpm when I close the choke partially, and it didn't react when I pulled off a vacuum line.

 So here's where it wound up.

                  Stock.         Now
Idle tubes,   .038.        .038
DCR'S,          .054.        .054
UIAB'S,         .069.        .069
LIAB'S,         .062.        .070
Bypass air,  .105.        .105
Idle dschg,  .086.        .086
Float,         12/32.     12/32
PAB-Body,   N/A.        N/A
PAB-Horn,   .051.        .051
Noz. Bleed, .029.        .029
Main jets,    #72.         #70
Pri. Rods,    49M.        50M
P/V spring,  orange.   Blue
APT set,      3 3/4.      3 1/4
Sec. Rods.   DP.           DR
Hanger,         K.            K
SABT,s.        .026.       .026
Well holes,   .039.      .039
A/V spring,   3/4.       3/4
N/S asm.      .135.     .135

 Now anything with the secondaries is still to be determined by testing yet to be done. I'll update once I've got the secondaries dialed in.

 One thing that kept messing with me is that the AFR would fluctuate randomly like it had an internal leak, but multiple testing of the well plugs didn't reveal anything, and I kept remembering what Cliff says about these, "they seldom leak".
 But I've seen how the AFR gage reacts to a leaky plug and I swear it's leaking.
 Well after taking it apart after it sat overnight I noticed the pocket in the base plate was wet with fuel.
 And I kept seeing wetness on the primary well plugs too, so I removed all of them and threaded the holes and installed plugs and Marine Tex, now the AFR is definitely more steady and it sounds better too.

 

[77cruiser]

Sounds like you did a great job.

[GSP7]

Whats the 17080231"C" ?

This is what i have on the 1980 350 HD Truck 17080213 Rochester and Carter units.
[/quote

[Kenth]

C is the Carter mfd Quadrajet.

[GSP7]

I have a Rochester 17080213 that had 73 jets and 49 rods