Pir0San

quick question, when setting the float adjustment, and the float bowl top is upside down so that the adjustment can be made, is the float supposed to sit at 9/16 under it's own weight, or am I supposed to hold the float until it just touches the needle, and go from there?

oh, okay, I feel dumb now, , I'll try that out tomorrow and see what happens. Thanks!

Thanks for all of the help guys, I'm trying to trace this problem down. You are totally right, the oil in the dampner will not affect mixture or idle speed at idle, but will affect mixture when accelerating, but I'm sure you knew that :laugh: , I was just thinking that the velocity of the air pulling on the dashpot might have to correlate with the dampner oil.

yeah, mine are the stock 3 screw carbs from my 240Z. Why do the drain plugs make a difference, out of curiousity? Just to make sure I read what he said right, put the clear line on the bottom of the float bowl, turn the motor over until the fuel inside of the plastic line stabilizes (air is bled out), and the put the line up to the mark I made on the float bowl, and adjust the float setting until the fuel in the plastic line is at the same height as the fuel in the float bowl?

I found this site, and this is how the guy recommends I check my float bowl settings, does this sound right? SU Tech Pages

oh, good point, I see what you're saying. So, if I were to do some trial and error with the floats, would I want the float to be closer to the float lid (such as instead of 9/16, like 7/16), or would it be the other way around? Thanks for your help, I can honestly say that there is not a part on my Z motor that I have not touched.

could my problem also be related to the amount of air the butterflies allow to enter the cylinder/pull through the carburetor? If this is too far off, will it cause my mixture to be hard to set as well? I'm just trying to find the best idea possible before I break down and try to take it to a mechanic.

when rebuilding the carburetors, I set the floats to 9/16 as advised by victoria british (who I got my rebuild kit from). The reason I just replaced the float is because the float I replaced it with came off of an old dirty pair of carburetors, but the PO said the car ran with them...I'm lost as to what to do.

how would I check to see if the float level is where it should be?

I believe the N42 does have the square exhaust ports, and the N47 has the round exhaust ports with the exhaust liners. If the ZX turbo exhaust has square ports (like the P90/P90A should have), then it should be a direct bolt up.

Ok, I put a rebuilt my carburetors, and now I'm having problems getting them just right. I can't get the mixture just right. I can set the air flow with my unisyn, and I can drop the idle down to under 1000, but the mixture I can not get right. I have set the mixture nuts to 2 1/2 turns, but the car will bog out when I lift up on the lift pins, like it is going to die. No matter how much I turn the nut out, the car backfires out of the carburetors, which I am assuming is a lean situation, since it is mixed with the bogging out when I push the lift pins. My carburetor dampers are good, I have SU fluid from MSA in them, and I might end up using Marvel Mystery Oil to see if it makes any difference. When I have my choke on, the car runs good, but when it is off and the car is warmed up, it stumbles when going from idle, and can die if the throttle is not feathered just right. The nozzle and needle are not stuck, because when I lift the piston/dashpot, and I drop it, it slides down fast and makes a distinct clunk noise. What could cause this issue? I don't believe it to be my float settings, because I replaced them with another float that I have from another set of carburetors, and it didn't make a difference. If you want more information behind the matter, and what I've tried, see my thread at Zcar.com Any help is appreciated, I just finished rebuilding the engine, and I'm eager to get her back on the road and driving again!!