hac diagram?

[Nemesis Gnat]

does anyone have one? the only diagrams i have (the ones that everyone have floating around for desmogs) dont really tell me where each port on the hac hook up (the desmog diagram doesnt even show i hooked up, but i need it), they just show me a place on the spaghetti monster to plumb to... i wanna know where they run to ultimately as the monster needs to go. im desmogging btw if that changes anything...

Thanks!

 

[Nemesis Gnat]

also, since my searches arent helping too much, can someone clarify the green wire mod for me?

 

[2mbb]

How about these:

http://www.sweetillusions.org/toyota/6.pdf

http://www.sweetillusions.org/toyota/fj60_vacuum_routing.gif

 

[Nemesis Gnat]

they help a lot, but im still a liiil confused

correct me if im wrong here

-the top middle port goes to the port down low on the carb
-with the ports facing you on the hac, left or ride side goes to primary and secondary high speed circuits on carb? and how can i identify these on my carb (on the first attached picture, which one if closer to/ further from the head?)?
-and the bottom port goes to a T where it splits between the check valve/gas dealy and the distributor secondary

eh?

and anyone on the green wire mod?

Thanks for putting up with someone new this stuff!

 

[2mbb]

The primary port should be closer to the valve cover, because that's where the primary throttle bore is.

Otherwise I think you got it right. I could be wrong, but from the schematic, it doesn't seem that it matters much if you mix us the connections between the top three HAC ports. They are all opened at the same time. The schematic shows restriction orifices integrated into the carb ports, so the orifices control the flow that each circuit gets.

I don't know what the green wire mod is? Is this applying 12V switched power to the decel fuel cut valve, bypassing the control from the emissions computer?

 

[Nemesis Gnat]

ha well i learned something new about primary vs secondary barrels in the carb. Thanks for all the help 2mbb!

as for the green wire mod, im not entirely sure what it is... as far as i can figure... people with failing decel fuel cut systems do it to keep their motor from stalling on deceleration. i think

as far as why im wondering about it, mostly its cause im curious. in part it is because i think simpler is better in most cases (but not all) and with some more knowledge would debate doing this mod. as i understand it removes the vaccuum switch and allows me to remove the computer as its no longer doing anything... once again, i think

also, i think im getting symptoms that some people seem to have fixed by doing the green wire mod (mostly seemigly random stalling on hard deceleration)... so i wanna see if it fixes my issues

 

[Nemesis Gnat]

and oone more thing... according to one of the desmog diagrams i have (the one that jimc did up i think), the advance port from the carb runs to the secondary on the dist... but thats where the hac system should go... should i just switch them (hac to primary, advance to secondary), or run them stock (advance to primary, hac to secondary), or run both to the secondary with a T fitting?

 

[Nemesis Gnat]

anybody? bueller?

 

[FJ40Jim]

The reason the vac advance hose is connected to the dissy HAC fitting is to reduce the amount of vac advance. Stock USA dissy will have too much vac advance, causing serious spark knock at 1600-2200rpm.

Only other way to fix is to recurve the vac advance.

 

[Nemesis Gnat]

mmk, thanks yall