I turned on my 87 305 formy and this came out of CCqjet. I was reving it a bit and this pin looking thing flew out. Can someone tell me what this is, where it goes, and function? I keep having problems with this carb.

 

Found out its the main metering rod. How did it come out and how does it go back in? Pretty sure I have to take the top off.

 

That's a new one on me.

Yes, I'd think you'd need to take the air horn off.

 

five7kid is right you have to take the air horn off. (that is the top of the carb in your case) There should be 7 hex screws on top plus the 2 front bolts that hold the carb to the intake. There are also 2 little hex screws below the choke plate. Get a magnetic screwdriver or magnetic pick-up tool. You dont want to drop the screws into the intake. You will have to disconnect the vacuum diagram comming off of the choke and linkage. I believe there is a couple wire connections and one more linkage on the driver side of the carb that need to be removed.

 

I just saw your other thread about your carb after I read this one....after you put the air horn back on from cleaning the needle & seat, did you include the mixture solenoid plunger? It's the silver thing that sits on top of your primary metering rods, has a spring under it, looks like a spike with a wide head. The head has a notch in it to keep it from turning off center, maybe the notch wasn't lined up and the plunger head turned and let your rod fly out the vent? Just thoughts...

 

85blown thanks for explaining the process.

Eighty four I think I did put in back in. Will that cause the loss of power down low and not under acceleration?

What is the purpose of the rod that flew out and what happens if it not there? I am by no means going to leave it like that just having a noob moment.

 

Not sure it's possible for that rod to come out if it was installed correctly. You may want to post some pics of your carb as you remove the airhorn. Post them up and we can have a look-see.

 

It sure will. The metering rods are like a floodgate.....determines how much fuel gets metered into the jets; without one or both of them there, the fuel's just gonna dump in no matter what your throttle position is. It'll also run rich if your mixture solenoid plunger isn't functioning, but the metering rods have got to be in place underneath that plunger head in order to for the car to be driveable to any reasonable degree. When everything's back in place and the engine's running (or just the ign key is on), you should hear a ticking noise from the carb, that means your solenoid is functioning.

 

Finally had time to remove it. What do u guys think?

 

OK. The MCS 'hat' - the shiney metal thing that looks like an arrow pointed West should be rotated 90 degrees clockwise (it may have been in that position before the airhorn was removed, maybe not). The two primary mixture rods go into the primaries so that the top of each is under one end of the 'arrow' of the MCS - the 'hat' piece. You should be able to see the tubes they fit in. The springs on the primary rods keep them up out of the primaries until the MCS pushes them down. The MCS 'hat' should also have a spring on it to keep it up.

It's possible that when they were installed earlier the MCS 'hat' piece rotated into the wrong position. It would normally be kept in place by the MCS hold down screw which fits between the two tangs opposite the 'arrow' end. It's more likely, imo, that the primary rod that came out jumped out of position somehow during install.

Put everything back together properly. Before tightening anything down it's always a good idea to check action of the MCS. With the airhorn on and the IAB screw removed, a secondary rod (or other handy piece) can be used to poke into the IAB hole and verify that the MCS is clicking up and down with the correct amount of travel (1/8").

 

Thanks will try to work on that tonight.

 

Put the metering rod back om and air horn. Everything was fine till I test drove it. It sputters and hesitates real bad. Checked all connections electrical, air hoses, screws and all was fine. Dont know whats the problem now.