high idle 1500rpm after desmog

Joined
Dec 13, 2008
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I can't get the cruiser to idle under 1500 rpms after my desmog. here is what i have checked:

Timing (the whole procedure 1cyl tdc lined up on dizzy 7 degrees)
All vac lines seem to be connected correctly
Capped all unused vac lines
checked idle screw - fine

I can turn the air mix screw all the way in without any change of rpms. very wierd.
I sprayed the intake down with carb cleaner and the idle raises slightly. But i can also take any vac line right off the intake with no change in rpms. So a leaky gasket seems like woulded be enoughI replaced the header, intake, and rebuilt carb. I used an oem mani gasket which was very thick and tourqed bolts. The parts i put on seemed free of warp spots when checked with a straight edge. Does it matter running it without the air filter housing?? typically no but i just figure i would ask. the carb is sucking some serious air... Tell me what you think to hopefully make tomarrow a better day. thanks
 
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bump someone help me. I see in posts the vaccum advance to the carb hooked up to either ports on the dizzy. which is correct or does this make a difference?? could this be my problem?
 
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Where are you taking your vacuum for your distributor advance? Carb port? Did you check your timing with your vacuum line to your distributor detached and plugged?
 

Trapper50cal

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okay....

Check this out:

https://forum.ih8mud.com/60-series-wagons/266009-optimal-idle-rpm.html

FJ60Cam's last post has a set of photos from the FSM and one of the screws listed is the Idle Mixture adjusting Screw on the side of the carb facing the valve cover...I think this is the screw I had to expose by drilling/prying the little cap covering it off. If you haven't done this then I think you have to...then follow the procedure to adjust. It may involve some timing too. I think its called the "lean down" method? is that correct?
 
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Dec 13, 2008
Messages
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Where are you taking your vacuum for your distributor advance? Carb port? Did you check your timing with your vacuum line to your distributor detached and plugged?
okay....

Check this out:

https://forum.ih8mud.com/60-series-wagons/266009-optimal-idle-rpm.html

FJ60Cam's last post has a set of photos from the FSM and one of the screws listed is the Idle Mixture adjusting Screw on the side of the carb facing the valve cover...I think this is the screw I had to expose by drilling/prying the little cap covering it off. If you haven't done this then I think you have to...then follow the procedure to adjust. It may involve some timing too. I think its called the "lean down" method? is that correct?
I am taking my vacuum from one of the ports below next to the idle air mix screw (valve cover side). I adjusted my timing with the vac line disconnected but not plugged. I can basically plug and unplug anything i want and the idle stays the same. Only way to make it change rpm is to move the dizzy. rebuilt carb.
 
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Dec 7, 2002
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There are 4 little ports on the base of the Aisin Carb on the passenger side. If you look at them from the passenger side, the one on the top left has a 90 degree bend; hook your fuel cut solenoid up to it. Going counter clockwise, the next one down is for the distributor. Continuing counterclockwise; the next one is plugged if you are desmogged. Again, continuing counter clockwise; the last one is for a line to the bimetalic switching valve on the thermostat housing.
Is your choke hung up?
 
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There are 4 little ports on the base of the Aisin Carb on the passenger side. If you look at them from the passenger side, the one on the top left has a 90 degree bend; hook your fuel cut solenoid up to it. Going counter clockwise, the next one down is for the distributor. Continuing counterclockwise; the next one is plugged if you are desmogged. Again, continuing counter clockwise; the last one is for a line to the bimetalic switching valve on the thermostat housing.
Is your choke hung up?
i have a these right except for the last . I have the valve on the therm housing plugged. If there is one line going there from the carb do i just cap off one of the two lines??? which sensor is it i know there are two right next to each other.

also the one going to the dizzy does the vac line go to the outside of the diafram or the inside. ( i have it on the inside one with the other blocked off)
thanks a lot
 

Trapper50cal

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Of the two BVSV's keep the higher one (the one closer to the middle) and the lower (or outer one) gets plugged
 
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well it eas part of the rebuilt carb hanging up. also i found the dizzy advance on the dist. is bad.
 
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Bristol, Rhode Island
IT's not just the idle screw, you also need to adjust the fast idle screw. Basic carb tuneup all outlined in the factory service manual.

I had the same issue after I replumbed all my vac line. My guess is that it's actually a good thing. You've solved the problem, your carb was adjusted to work with the inefficiencies. Now it's overcompensating.

You'll need to drill out the protective cap hiding that screw and adjust per the manual.
 
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