Quick background on my FJ40:
1974 with stock 1.5F engine.
Head rebuilt by JimC (FJ40Jim). Manifold resurface/machined through him as well.
New distributor from City Racer (non-US distributor) running points. Points gap set to .018.
Original carb--it is Cali-spec. Rebuilt. I sent it to FJ40Jim so that he could dial it in on his engine. Idle solenoid working.
Timing is set to 12 degrees BTDC. Set here because this seemed to give me the best vacuum without pinging.
Valves adjusted then readjusted and then readjusted again to make sure that they are set to .008 and .014 (maybe a little on the loose side--like .009 and .015 because I don't want to be too tight). This was done when the engine was nice and hot.
All new gaskets--head and manifold. Manifold is OEM. I also used carb gaskets above and below the carb insulator.
OEM PCV valve--new. Using vacuum hose (not heater hose), no leaks.
Brake booster not leaking.
I have made sure that all the bolts and nuts are torqued to spec per the FSM--all head bolts to 90ft-lbs, rocker supports to 28 ft-lbs (10mm) and 18 ft-lbs (8mm), manifold nuts to 22ft-lbs.
When the choke is completely opened, idle drops to around 450RPM. She does not die--she will continue to run, but just barely. I have sprayed carb cleaner every where I can think of to try and find a vacuum leak--all around the carb base, intake manifold with no success in finding a leak.
I am assuming that there is a vacuum leak because of the way the needle flickers and the vacuum is too low (I am not at altitude).
Vacuum is checked through the brake booster hose.
Here are some videos:
Vacuum at 650RPM
2nd video vacuum at 650
Vacuum at 850RPM
Vacuum at 1000RPM
What do these readings tell ya'll. Is this consistent with a vacuum leak? Could a chunk of crud gotten into my idle circuit in the carb? I have spent the last 2 weekends trying to find the cause for this and I am coming up empty. Any and all help is very much appreciated.
1974 with stock 1.5F engine.
Head rebuilt by JimC (FJ40Jim). Manifold resurface/machined through him as well.
New distributor from City Racer (non-US distributor) running points. Points gap set to .018.
Original carb--it is Cali-spec. Rebuilt. I sent it to FJ40Jim so that he could dial it in on his engine. Idle solenoid working.
Timing is set to 12 degrees BTDC. Set here because this seemed to give me the best vacuum without pinging.
Valves adjusted then readjusted and then readjusted again to make sure that they are set to .008 and .014 (maybe a little on the loose side--like .009 and .015 because I don't want to be too tight). This was done when the engine was nice and hot.
All new gaskets--head and manifold. Manifold is OEM. I also used carb gaskets above and below the carb insulator.
OEM PCV valve--new. Using vacuum hose (not heater hose), no leaks.
Brake booster not leaking.
I have made sure that all the bolts and nuts are torqued to spec per the FSM--all head bolts to 90ft-lbs, rocker supports to 28 ft-lbs (10mm) and 18 ft-lbs (8mm), manifold nuts to 22ft-lbs.
When the choke is completely opened, idle drops to around 450RPM. She does not die--she will continue to run, but just barely. I have sprayed carb cleaner every where I can think of to try and find a vacuum leak--all around the carb base, intake manifold with no success in finding a leak.
I am assuming that there is a vacuum leak because of the way the needle flickers and the vacuum is too low (I am not at altitude).
Vacuum is checked through the brake booster hose.
Here are some videos:
Vacuum at 650RPM
2nd video vacuum at 650
Vacuum at 850RPM
Vacuum at 1000RPM
What do these readings tell ya'll. Is this consistent with a vacuum leak? Could a chunk of crud gotten into my idle circuit in the carb? I have spent the last 2 weekends trying to find the cause for this and I am coming up empty. Any and all help is very much appreciated.
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