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Mazda Projects \ Stock Carburetor Troubles (1993 B2200)Stock Carburetor Troubles (1993 B2200)
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zackarytucker87
+1y
Okay so I definitely i messed up my regular idle. It would idle lower than regular upon starting so i have to warm it up with the choke every start if it hasn't been ran in more than an hour or 2 . After the choke warms it up and i've driven for a good bit, it would idle slightly higher but not high enough to be normal.
So in an attempt to adjust my idle because my hunch is that it was thrown off in my little "drive" one day. The yellow arrow points to the bolt i tightened in my attempt to tighten the linkage because i thought that was why my idle was lower. But my truck shut off and wouldn't stay on unless my foot was on the pedal. I tried putting the bolt back to normal but it wouldn't work, it still did the same thing. So i tightened my throttle cable to hold the idle up high enough to stay on. (Zip-ties on the cable at the gas pedal.) It works but i don't know if this is fine or not.
One other thing is that my choke idle has always been high (like 3k rpm). How do i lower the choke idle? I put green arrows to screws i'm not sure about.
So in an attempt to adjust my idle because my hunch is that it was thrown off in my little "drive" one day. The yellow arrow points to the bolt i tightened in my attempt to tighten the linkage because i thought that was why my idle was lower. But my truck shut off and wouldn't stay on unless my foot was on the pedal. I tried putting the bolt back to normal but it wouldn't work, it still did the same thing. So i tightened my throttle cable to hold the idle up high enough to stay on. (Zip-ties on the cable at the gas pedal.) It works but i don't know if this is fine or not.
One other thing is that my choke idle has always been high (like 3k rpm). How do i lower the choke idle? I put green arrows to screws i'm not sure about.
zanzer
+1y
The screw behind the choke heater really doesn't do much, it just pins the choke shaft to the linkage.
With the truck completely cold, remove the air clearner assembly and inspect the choke plate position. They should be fully open from the previous drive if you got the truck up to normal operating temp.
Then (with the truck still cold and not running) open and close the throttle and see if the choke resets itself to the closed position. It should reset to where the choke plates are almost closed. If not, you may need to adjust the choke heater position. If no one has done this on your truck before it will still have the 3 factory installed rivets. If it does you will have to drill them out and replace them with machine screws.
Once the choke heater is adjustable, loosen the screws and rotate it until the choke plates are almost fully closed...but not too tight. Also, make sure you have a good 12V+ source hooked up to the heater so it will start to open once the truck is cranked.
Now, with the choke properly adjusted; fire the truck up and see where what RMPS's it's running with the choke fully applied. If it's too high you'll need to back off on the fast idle cam adjustment (high idle adjustment screw in the pic). If it's too low, screw it in some until you get the desired RPM's. I usually set mine for around 1500-1750. The truck should run at or around this RPM setting until the choke starts to warm up due to the 12V applied to the bi-metallic spring inside the heater housing (although it will hold this RPM until you "blip" the throttle at which time the fast idle cam is mechanically released from it's set position between it and the fast idle adjustment screw).
Let the truck warm up with the choke applied, I usually wait for the temp gauge to move up about a 1/4 from cold or so. At this point you should be able to snap the throttle and release the choke. If everything is working properly, the heated choke spring will have tension built up from being warmed from the 12V applied to it and the choke plates will open when you snap the throttle and release the fast idle cam from the adjustment screw.
At this point you should be able to start tweaking the warm idle setting. If it's too low to maintain a stable idle, run the idle adjust screw in until you have 800-850 PRM's. Too high, run it out to bring the RPM's down.
Now, either let the truck sit and idle or take it out for a drive until it reaches normal operating temperature (I prefer the test drive method myself). Once it's fully warmed up recheck the idle to see if it's still 800-850 RPM's. If not, adjust accordingly.
Once the truck has completely cooled down, i.e. the next day or at least where the valve cover is cool to the touch...pump the throttle to set the choke, fire the truck up, then go thought the warm up and run procedure again to verify that the changes have taken effect and everything is operating properly.
Kind of a long post I know, but hope it helps
With the truck completely cold, remove the air clearner assembly and inspect the choke plate position. They should be fully open from the previous drive if you got the truck up to normal operating temp.
Then (with the truck still cold and not running) open and close the throttle and see if the choke resets itself to the closed position. It should reset to where the choke plates are almost closed. If not, you may need to adjust the choke heater position. If no one has done this on your truck before it will still have the 3 factory installed rivets. If it does you will have to drill them out and replace them with machine screws.
Once the choke heater is adjustable, loosen the screws and rotate it until the choke plates are almost fully closed...but not too tight. Also, make sure you have a good 12V+ source hooked up to the heater so it will start to open once the truck is cranked.
Now, with the choke properly adjusted; fire the truck up and see where what RMPS's it's running with the choke fully applied. If it's too high you'll need to back off on the fast idle cam adjustment (high idle adjustment screw in the pic). If it's too low, screw it in some until you get the desired RPM's. I usually set mine for around 1500-1750. The truck should run at or around this RPM setting until the choke starts to warm up due to the 12V applied to the bi-metallic spring inside the heater housing (although it will hold this RPM until you "blip" the throttle at which time the fast idle cam is mechanically released from it's set position between it and the fast idle adjustment screw).
Let the truck warm up with the choke applied, I usually wait for the temp gauge to move up about a 1/4 from cold or so. At this point you should be able to snap the throttle and release the choke. If everything is working properly, the heated choke spring will have tension built up from being warmed from the 12V applied to it and the choke plates will open when you snap the throttle and release the fast idle cam from the adjustment screw.
At this point you should be able to start tweaking the warm idle setting. If it's too low to maintain a stable idle, run the idle adjust screw in until you have 800-850 PRM's. Too high, run it out to bring the RPM's down.
Now, either let the truck sit and idle or take it out for a drive until it reaches normal operating temperature (I prefer the test drive method myself). Once it's fully warmed up recheck the idle to see if it's still 800-850 RPM's. If not, adjust accordingly.
Once the truck has completely cooled down, i.e. the next day or at least where the valve cover is cool to the touch...pump the throttle to set the choke, fire the truck up, then go thought the warm up and run procedure again to verify that the changes have taken effect and everything is operating properly.
Kind of a long post I know, but hope it helps
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