No particular questions but sharing this as I go through the process of getting my freshly rebuilt 1974 up and running. Its a 1974 US market FJ40 I've owned for almost 20 years and dragged across the world and back. Here is a build thread that needs some updating...Builds - 1974 FJ40 Restoration Build Thread
I had some initial timing problems which many of you helped with along the way...https://forum.ih8mud.com/threads/methodical-first-start-process.1199635/post-12986555
Now I am tackling another round of issues which hopefully will be quick, but I am taking a methodical an involved approach this time rather that just following the FSM and Haynes...so here is what I am dealing with and doing...no particular questions but feel free to post observations and suggestions if you wish...
Truck was initially idling high but OK and was not responding as expected to mixture or throttle stop changes. I suspect vacuum leaks so I blocked off each vacuum hose 1 by 1 and didnt find any change. Vacuum gauge reads almost nothing when it was idleing and now even when briefly idling before it dies. Like 3". Sprayed some carb cleaner around different spots and found the carb was leaking at the horn-to-base gasket. Put the truck away for the night. That leak is above the throttle plates so it certainly needs fixing but wouldnt explain the low vacuum reading on its own.
Next day started the truck up but now it wouldnt idle at all without 1/4 choke and even then just sputters out. Ot would start with full throttle and rev but wouldnt idle on its own. I have a air-fuel mix gauge and it shows rich at the rough idle but I havent found those gauges reliable when the motor isnt running close to right.
My plan is to re-rebuild the carb and go through every single place an intake leak coule be coming from, down to the intake manifold.
For posterity, my carb settings are...
Primary jet 1.20
Secondary jet 1.80
Primary idle/slow jet 60
Secondary idle/slow jet 80
Primary Venturi has #2 stamped on in, secondary has #4. Both are double-ring.
Power valve 80
I disassembled the carb and using a pane of glass sanded the air horn section and carb bases flat. Made a new gasket and used curil-t.
Cleaned out every passage in the carb including removing and cleaining the idle circuit and testing the solnoid. I saw some threads mention an o-ring falling apart and blocking the idle solnoid. I didnt find any o ring and also no evidence of debris.
Put the carb all back together last night and will work on the base and intake later today....
Thanks all end enjoy!
I had some initial timing problems which many of you helped with along the way...https://forum.ih8mud.com/threads/methodical-first-start-process.1199635/post-12986555
Now I am tackling another round of issues which hopefully will be quick, but I am taking a methodical an involved approach this time rather that just following the FSM and Haynes...so here is what I am dealing with and doing...no particular questions but feel free to post observations and suggestions if you wish...
Truck was initially idling high but OK and was not responding as expected to mixture or throttle stop changes. I suspect vacuum leaks so I blocked off each vacuum hose 1 by 1 and didnt find any change. Vacuum gauge reads almost nothing when it was idleing and now even when briefly idling before it dies. Like 3". Sprayed some carb cleaner around different spots and found the carb was leaking at the horn-to-base gasket. Put the truck away for the night. That leak is above the throttle plates so it certainly needs fixing but wouldnt explain the low vacuum reading on its own.
Next day started the truck up but now it wouldnt idle at all without 1/4 choke and even then just sputters out. Ot would start with full throttle and rev but wouldnt idle on its own. I have a air-fuel mix gauge and it shows rich at the rough idle but I havent found those gauges reliable when the motor isnt running close to right.
My plan is to re-rebuild the carb and go through every single place an intake leak coule be coming from, down to the intake manifold.
For posterity, my carb settings are...
Primary jet 1.20
Secondary jet 1.80
Primary idle/slow jet 60
Secondary idle/slow jet 80
Primary Venturi has #2 stamped on in, secondary has #4. Both are double-ring.
Power valve 80
I disassembled the carb and using a pane of glass sanded the air horn section and carb bases flat. Made a new gasket and used curil-t.
Cleaned out every passage in the carb including removing and cleaining the idle circuit and testing the solnoid. I saw some threads mention an o-ring falling apart and blocking the idle solnoid. I didnt find any o ring and also no evidence of debris.
Put the carb all back together last night and will work on the base and intake later today....
Thanks all end enjoy!
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