any desmog kits available fj40jim
My Desmog Thread
- Thread starter fowldarr
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Prolly best to ask here: Desmog components
thanks spike strip
been doing a bunch of work on my 60 lately, going through desmog stuff again,
Adding BVSV1 back into the circut, that should help cold weather driveability this winter. If you are BVSV'less like i am and drive in the cold, even with a ported vac source it can be hard to keep the engine running when you first set out..
found my intake / exhaust mani gasket had failed pretty badly, so replaced that with OEM toyo gasket and had my mani milled flat, sealed nicely now - likely for the first time ever since i did my original desmog back in 2009.
did a lean drop and retune of the carb after i sealed up all the vac leaks from the manifold,
here's where im at , and ive got a question for Jim or anyone who may know..
when i pull my choke 90% of the way on a hot engine, i get the corresponding idle up to 1800-2000 rpm as it should.
If i pull my choke 100% , it will kill the engine, hot or cold. so - is this an issue with the choke opener or choke breaker? how should i trouble shoot that? or should i..
Adding BVSV1 back into the circut, that should help cold weather driveability this winter. If you are BVSV'less like i am and drive in the cold, even with a ported vac source it can be hard to keep the engine running when you first set out..
found my intake / exhaust mani gasket had failed pretty badly, so replaced that with OEM toyo gasket and had my mani milled flat, sealed nicely now - likely for the first time ever since i did my original desmog back in 2009.
did a lean drop and retune of the carb after i sealed up all the vac leaks from the manifold,
here's where im at , and ive got a question for Jim or anyone who may know..
when i pull my choke 90% of the way on a hot engine, i get the corresponding idle up to 1800-2000 rpm as it should.
If i pull my choke 100% , it will kill the engine, hot or cold. so - is this an issue with the choke opener or choke breaker? how should i trouble shoot that? or should i..
The choke opener vacuum source is routed through the lower BVSV in the T-stat housing.
Once the coolant warms up, the BVSV opens, which allows the Choke Opener to keep the choke open when the engine is warm.
Maybe test to see if it is functioning correctly.... Or install one... Or install an electric VSV solenoid to allow you to flip it on and off in the cab.
Once the coolant warms up, the BVSV opens, which allows the Choke Opener to keep the choke open when the engine is warm.
Maybe test to see if it is functioning correctly.... Or install one... Or install an electric VSV solenoid to allow you to flip it on and off in the cab.
yeah, thx output.
im desmogged on a OEM carb by Jim C, so from what i can see i dont have a choke opener, but i do have a choke breaker with the green vtv installed. i'll test it and see if its working
im desmogged on a OEM carb by Jim C, so from what i can see i dont have a choke opener, but i do have a choke breaker with the green vtv installed. i'll test it and see if its working
The Choke Beaker only cracks open the choke a little bit (when it's working). Yes. If it's diaphragm is shot, the choke cable would fully seal off the carb throat when fully pulled.
If the engine is warmed up and no Choke Opener is installed on the carb, the engine will definitely bog if the choke cable is pulled out all the way. That's what the choke opener was designed to prevent.
(Dwg attached for others to reference)
If the engine is warmed up and no Choke Opener is installed on the carb, the engine will definitely bog if the choke cable is pulled out all the way. That's what the choke opener was designed to prevent.
(Dwg attached for others to reference)
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The CB has the VTV (delay valve) in the circuit. So if the engine is just started, the CB has not yet gotten enough vacuum to open. If this is a concern, the VTV can be deleted like a non-USA carb so the CB will break open the choke immediately upon startup.
Jim,
let me back up a second.
so while doing the lean drop, idle and fast idle adjustments, a few times i was able to pull 100% full choke, adjust the idle to 1800 and it would just sit there and run at that speed.
after i had everything dialed in with the adjustments, i can no longer pull 100% full choke.. it kills the engine. i can run like 90% choke.
so knowing that the vehicle should be able to start and idle on full choke (100% pulled), it leads me to think i either did something wrong, or something isnt working as it should..
this is on a US desmogged OEM carb that you did for me back in 09'
let me back up a second.
so while doing the lean drop, idle and fast idle adjustments, a few times i was able to pull 100% full choke, adjust the idle to 1800 and it would just sit there and run at that speed.
after i had everything dialed in with the adjustments, i can no longer pull 100% full choke.. it kills the engine. i can run like 90% choke.
so knowing that the vehicle should be able to start and idle on full choke (100% pulled), it leads me to think i either did something wrong, or something isnt working as it should..
this is on a US desmogged OEM carb that you did for me back in 09'
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Try deleting the VTV & just run a straight vac hose from front of carb to CB. If "problem" goes away, then drive & enjoy.
^ Wilco. i'll give it a go.
am i right in thinking that the desmogged carb you did does not have a choke opener?
am i right in thinking that the desmogged carb you did does not have a choke opener?
If you have a larger vacuum actuator below the smaller choke breaker actuator, then you've got a Choke Opener. Some carbs I've seen (and a spare I have) don't have it.
Red circle around choke opener actuator below.
Red circle around choke opener actuator below.
no tengo.
suppose the issue could just be that. no choke opener + full choke on a hot engine = engine dies. makes sense right?
Jim are you able to run full choke on a hot engine on your desmogged carbs when you test them?
suppose the issue could just be that. no choke opener + full choke on a hot engine = engine dies. makes sense right?
Jim are you able to run full choke on a hot engine on your desmogged carbs when you test them?
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The CB breaks opens the choke far enough that the choke will not drown the engine, even if pulled all the way on a warm, idling engine.
The somewhat redundant CO opens the choke blade so far that the choke cannot drown the engine even if pulled while driving on the highway.
Since you are not so stupid as to inadvertently apply full choke while driving on the highway, the CO and it's controls go away during a desmog. The CB is retained as a convenience feature.
The somewhat redundant CO opens the choke blade so far that the choke cannot drown the engine even if pulled while driving on the highway.
Since you are not so stupid as to inadvertently apply full choke while driving on the highway, the CO and it's controls go away during a desmog. The CB is retained as a convenience feature.
got it.
so at this point, i'll try the CB minus the VTV and report back.
more to come..
so at this point, i'll try the CB minus the VTV and report back.
more to come..
Just got this rig, and just read thru this entire thread. I think mine has been partially desmogged. The two large hoses coming off air cleaner are gone, one taped over like a lot of people do instead of the caps from Jim C. The other just open. One vacuum line coming off EGR valve capped with golf tee. Line coming off air cleaner to VSV(2) for AI plugged with golf tee. Air pump doesn't have anything coming off it, looks like hoses just hanging disconnected under air cleaner? Makes air pump look like an alternator. Does air pump have elec connections? EGR stuff all there, metal spaghetti all there, passenger side looks stock. Air rail still connected. HAC and A/C idle up connected. Fuel cut connected. BVSVs still connected. It starts and runs fine. Might be a good winter project. Thanks for all who posted. This is some good reading and ref material. Saved Desmog file from Greg to my iPad for future ref.
So I am attempting to desmog an '86 2F installed in my 40 series. I am missing the vcv on the driver side. Can I get away with the desmog without it or do I have to have one for the evap system.
Also, I cannot get the truck to idle correctly. The PO had it connected all sorts of weird ways so when I followed the desmog thread I thought it would heal the high idle. Now I can't get it to idle.
I left my shop tonight ready to burn my 40. I need some collective mud help to get it going. It'll idle if the choke is pulled and will even run for a bit after the choke is let out. But once you hop in to drive it dies as soon as you put it in gear and put your foot on the brake.
Also, I cannot get the truck to idle correctly. The PO had it connected all sorts of weird ways so when I followed the desmog thread I thought it would heal the high idle. Now I can't get it to idle.
I left my shop tonight ready to burn my 40. I need some collective mud help to get it going. It'll idle if the choke is pulled and will even run for a bit after the choke is let out. But once you hop in to drive it dies as soon as you put it in gear and put your foot on the brake.
Vacuum leak
What us your idle vacuum reading?
@Stumpalama well I probably need to check that idle reading. I'll see if I have a vacuum gauge tomorrow.
So a leak would cause it to run that poorly?
So a leak would cause it to run that poorly?
