My Desmog Thread (3 Viewers)

[FJ40Jim]

Kambo, I don't know where to start with that...
You could start by getting it closer to the desmog schematic.

 

[Kamboman77]

Kambo, I don't know where to start with that...
You could start by getting it closer to the desmog schematic.

1

Thanks jim hey how can i send u the carb and dizzy and how much would it b

 

[Ketzer]

Which one of these 3 ports is the correct one for the advance on the distributor...?

 

[NeverGiveUpYota]

Which one of these 3 ports is the correct one for the advance on the distributor...?

That picture is super hard for me to see well but the advance on the carb is the short one furthest to the firewall almost out of sight.

 

[Ian Crawford]

OK... Wow there is a lot of great info and knowledge here. I wanted post the diagrams I marked up and used, I believe them to be accurate and they certainly helped me shed some light on things (for myself). They were marked up using info from this thread and others.

I hope it can help some of you, too!

 

[sheepdawg]

What does the fuel cut vacuum switch do? or what is it's purpose? Also, where does the electrical connection go to? Mine may have been eliminated (i.e.. cut off) during my mickey mouse desmog. If so, what will I need to do, since I am reinstalling a fuel cut vacuum switch?

As always, any help is greatly appreciated.

 

[FJ40Jim]

Fuel cut vac switch senses high vacuum, indicating the truck is coasting with throttle closed, so computer can turn off ICS to prevent over-rich condition when coasting.

See page 3-44 in the FSM for more info.

 

[deltapine1]

Look for a single green wire which would have run to the fuel cut off solenoid

 

[heardofweenies]

Hey guys,
I was hoping to get a desmog kit and a step by step instructions for dummies like myself for a 1978 FJ40. I would hate to start making this thing not run right with the desmog, so i'm hoping I could use your expertise so I can get this ready for my elk trip on Oct 20th. After reading some of the forums and seeing all your posts specifically on the 53 page thread, I have learned that there could be some issues if not done correctly and being in the high altitude I'm afraid of screwing something up. This post looks more for a 60, so maybe a few less steps on a 78 40. I seen that Jim the Jedi has been involved quite a bit and I have emailed him as well for a kit, so hopefully he's still available.
Thanks

 

[1911]

Hey guys,
I was hoping to get a desmog kit and a step by step instructions for dummies like myself for a 1978 FJ40. I would hate to start making this thing not run right with the desmog, so i'm hoping I could use your expertise so I can get this ready for my elk trip on Oct 20th. After reading some of the forums and seeing all your posts specifically on the 53 page thread, I have learned that there could be some issues if not done correctly and being in the high altitude I'm afraid of screwing something up. This post looks more for a 60, so maybe a few less steps on a 78 40. I seen that Jim the Jedi has been involved quite a bit and I have emailed him as well for a kit, so hopefully he's still available.
Thanks

My Desmog Keeping HAC Lots of Pics

 

[heardofweenies]

Thanks man. So, how much difference is there between the FJ60 (pictured) and a 1978 FJ40? I would assume there are a few more ports to deal with on the 60 and noticing the new card build by Jim C, does that have to be done as well.?

 

[FJ40Jim]

Here's a thread for 78 desmog:

Removing Federal Emissions Package

 

[cbenowen]

Just finished cleaning up a messy desmog by the PO. Used to have a Holley carb that I replaced with an aftermarket City Racer carb and added a stock air cleaner. Removed old rusted cat, replaced with 2.5' straight pipe and new muffler with exhaust exit out side behind rear wheel.

Also , I saw a post by @FJ40Jim that recommended switching the vac advance to the secondary if at sea level. That seemed to help considerably with the engine pinging and runs a little better now. Set timing to 10*

The truck drives nicely and pulls strong. Only issue I seem to be having now is a slightly rough idle with an occasional skip or stumble but nothing major. Also, occasionally I get a slight bog down in 2nd gear at 2500 rpm. I've never driven another FJ60 so I have nothing to compare it to.

Below are some pictures. If anybody has any recommendations, please let me know. I can take more pictures if needed.

 

[NeverGiveUpYota]

Just finished cleaning up a messy desmog by the PO. Used to have a Holley carb that I replaced with an aftermarket City Racer carb and added a stock air cleaner. Removed old rusted cat, replaced with 2.5' straight pipe and new muffler with exhaust exit out side behind rear wheel.

Also , I saw a post by @FJ40Jim that recommended switching the vac advance to the secondary if at sea level. That seemed to help considerably with the engine pinging and runs a little better now. Set timing to 10*

The truck drives nicely and pulls strong. Only issue I seem to be having now is a slightly rough idle with an occasional skip or stumble but nothing major. Also, occasionally I get a slight bog down in 2nd gear at 2500 rpm. I've never driven another FJ60 so I have nothing to compare it to.

Below are some pictures. If anybody has any recommendations, please let me know. I can take more pictures if needed.

View attachment 1578097


View attachment 1578098 View attachment 1578099 View attachment 1578101

If you want your vac adv on the secondary port you’d need that red hose to the outer port on the pot. The inner port is the primary and if your set at 10 plus the inner at 13 naturally, it would seem to me that your too advanced. Have you checked both w/ a mityvac to be sure they even hold vacuum? Often the inner port is the one that’s fried too.

 

[cbenowen]

If you want your vac adv on the secondary port you’d need that red hose to the outer port on the pot. The inner port is the primary and if your set at 10 plus the inner at 13 naturally, it would seem to me that your too advanced. Have you checked both w/ a mityvac to be sure they even hold vacuum? Often the inner port is the one that’s fried too.

I see that now. I think I misunderstood one of the posts on here discussing the primary and secondary. Although it seems to be running better they way I have it with no more pinging. I haven't checked to see if they hold vacuum. I'll have to get a mityvac.

 

[NeverGiveUpYota]

Take the cap off the diz... then It’s possible you could put a stretch of silicone hose on the port and suck on it hard. If you see movement of the governors then the diaphragm isn’t blown, if not then it is... but thats only if you’ve got a good set of lungs on you. Definetly not a tried and true test.

 

[S4Cruiser]

Holy crap this thread is a monster!!

Could someone please confirm my planned next steps below?

Desmogged 1987 2F with large cap dizzy (not recurved). Static Timing set at 7* and 650rpm idle. Vacuum advance hooked to primary (inner) pot on the carb. I have pinging even with premium fuel.

Move vacuum advance to the outer port on the distributor which should hopefully eliminate the pinging??

 

[FJ40Jim]

Yes, moving to the outer fitting will reduce max vac advance from 20° to 7°.

It may still rattle because the mechanical advance limiter pin is eroded, giving too much mechanical advance, starting too soon.

 

[S4Cruiser]

Yes, moving to the outer fitting will reduce max vac advance from 20° to 7°.

It may still rattle because the mechanical advance limiter pin is eroded, giving too much mechanical advance, starting too soon.

Super, thanks Jim! I should just swap in my recurved by you dizzy but I wanted to try getting a non curved one to work too.

When I swap in the recurved one, I should then use the inner pot, correct?

 

[FJ40Jim]

Yes, the inner pot should be OK with the mechanical side recurved. If the engine is particularly healthy and operating at very low density altitude, it may still rattle a bit. In that case, dial back the base timing a couple degrees.