Carb question

[greenkeeper]

I just put in a new Rochester quadrajet 4 bbl in my 87 R-305.7 350 .  I cannot seem to get the secondary jet plate to open causing my engine to bog down and lose power? Any thoughts on what the problem might be?

[VileZambonie]

Your question/statement doesn't make much sense. You'll have to elaborate.

[DnStClr]

It sounds like the secondary throttle plates aren't opening. Is that right greenkeeper? With mechanical secondaries, they're on a shaft, and the shaft for the secondaries is tied to the shaft of the primary throttle plates by a lever. The primaries open so far, and it causes the secondaries to open via the lever.

[greenkeeper]

Yes the secondary plates are on a lever.  The choke is an electric heat activated system.  when the truck warms up the choke kicks off but the secondary plate does not open.  Is there some sort of adjustment that needs to be made?

[HAULIN IT]

Are you talking about the "Secondary air flap" (with the air cleaner off, it's there on top you can push it open & it springs back shut) ? If so, It does not open by working the throttle, it is vacuum "held shut".  The bottom (secondary throttle blades) open with the throttle & once the vacuum has dropped, the pull-off  (round thingy on the Right front of the carb, with the little hose) lets the air flap open in relationship to the vacuum, the air pushing down as the vehicle is moving opens it. Hope this helps, If this isn't what part you are referring to, try in a little more detail. Hope this helps,  Lorne 

[greenkeeper]

 That is the plate I'm talking about. So it runs off vacuum pressure. I got it.  I'll have to check my vacuum lines to make sure everthing is connected properly.  i don't know why its lacking power. Seems to be running rich in 3rd gear. Going up hills its even worse.  The Chilton manual says that there is an adjustment that can be made to set the vacuum advance for the plate. You loosen the cover screws on the coil and turn it toward the furthest point, then bend the linkage until it settles in the middle of bracket. Does that sound familiar It an m4me Rochester carb. Any info would be helpful.

[HAULIN IT]

Green, It doesn't "run" off vacuum pressure, the vacuum holds it shut. In the basics of a gas engine, it won't "run rich" just in Third gear. A given air/fuel ratio can & will change with RPM on a engine with a carb on them. Is it blowing Black smoke going up the hill?
  Yes there is an adjustment on the air flap tension. However, if you can push the plate open with little pressure & it springs back shut...it's most likely close enough. I think you should leave it alone at this point. On an '87, I believe it will be a torx screw (the older ones were an allen). It is on the Right rear corner of the carb. You will see a flat screwdriver slotted screw, just under the casting is where you loosen the Torx screw. Note: The spring will unwind if your not holding the flat slotted screw!
 The description you posted sounds like the electric choke adjustment, not the Secondary air flap.
 I would check on an ignition problem as a possibility for your "worse up hills" also LEAN would be more likely, maybe check your fuel pressure or fuel line for kinks or a clogged filter. Just a couple thoughts, Lorne