My Desmog Thread

[Zack1978]

Study these...They will make perfect sense eventually...

Drivers side...

Passenger side...

Carb (valve cover side) 4 available ports here, I used 2 (distributor advance & old EGR for Evap valve)

Labeled...Hopefully for clarity. Also included are the choke opener(green) & choke breaker(yellow) on carb

Ok so the diagram in this pic is the Jim C "desmog" diagram? Also Jim rebuilt my Dizzy not that long ago, but it was set up for a smog truck, do I have to send it back? And the carb, I have to plug up all the ports there? And what diameter is the vacc hose? Is "Spectra" the best place to get the hose? What a confusing mess this entire desmog thing is!

Thanks,
Zack

 

[Zack1978]

I am so confused from reading this thread! I went to college and even have my masters degree, but the FJ60 smog system makes me feel very stupid!


Zack

 

[FJ40Jim]

Ok so the diagram in this pic is the Jim C "desmog" diagram?
Also Jim rebuilt my Dizzy not that long ago, but it was set up for a smog truck, do I have to send it back?
And the carb, I have to plug up all the ports there?
And what diameter is the vacc hose?
Is "Spectra" the best place to get the hose?
What a confusing mess this entire desmog thing is!

Yes.
No, not a requirement. The governor bushing was replaced, that's half the fix right there.
No, just the 3 HAC fittings.
1/8" ID silicon hose. PN 5236K832 at mcmaster.com.
It's only confusing 'cause of the craptastic diagrams that somebody scribbled on a bar napkin 8 years ago.

 

[aythya]

HELP!!!

Newb... First of all so forgive me. I have FSMs and have studied. I have read this post three times now and still confused. I have an 87fj60 of questionable desmog with a Holley carb. I am trying to go back stock (cruiser parts rebuilt carb) and air box. From pics I seem to be missing parts for the correct desmog. Where should I begin, short of bolting on the carb?

Truck runs rich (blows black debris out of exhaust when I crank it) often I have to hold accelarator to floor to crank. Choke light is on constantly

I would like to get stock fuel delivery prior to adjusting timing and valves...

apologies for the long post....

 

[biggdanny]

how bout under sea level i live in a deep sea level valley

 

[hank14]

how bout under sea level i live in a deep sea level valley

Add a tall snorkel to you list!
J/K, I don't thin a few feet below sea level would affect anything, but if oyu sent in your carb and distributor to Jim C, he might be able to adjust it appropriately.

 

[mudpaws]

I seriously like that blue hose! Yeah, I KNOW, we're DE-smogging here...

 

[Eporter]

What is the purpose of the stock VCV valve that sits near the distributor, and how is it best incorporated into a desmog?

It is #50 at the top of the "STOCK VACUUM LINE DIAGRAM"

There are no labels, but we will all visualize that it is labeled as such:

The top port, "1" goes to the Air Cleaner.

The side ports, on left and right, are "2" and "3" and are T'd together and run to the distributor.

The bottom port "4" goes to the 3-port plug on the intake manifold that is referred to as the "Gas Port" on the DESMOG diagram.

BUT! On the DESMOG diagram, it is rather confusing as to which port of the VCV is which, as the layout on the diagram does not seem to reference the physical part.

There are 2 lines T'd together that go to the Air Cleaner. The line on the right end of the VCV goes to the distributor. The line at the top left corner goes to the Gas Filter.

SO! Where does:
#1 go?
#2 go?
#3 go?
#4 go?

Why does the stock setup have TWO VCV lines T'd and going to the distributor, but the desmog only has ONE?

I've seen a lot of setups that just eliminate this VCV part, but I'm trying to keep it in the mix!

STOCK VACUUM LINE DIAGRAM:

DESMOG VACUUM LINE DIAGRAM:

 

[FJ40Jim]

The VCV is not a smog component. It controls the distributor cap ventilation. It is left alone when desmogging. It only needs connected to the manifold vacuum fitting to provide power to the system.

 

[Zack1978]

The VCV is not a smog component. It controls the distributor cap ventilation. It is left alone when desmogging. It only needs connected to the manifold vacuum fitting to provide power to the system.

Jim,
Would you like to take a vacation to beautiful NJ, and desmog my 60 while on vacation? I will pay for the flight and hotel!


Zack

 

[5280Hawk]

Hey Zack,

one thing i discovered (and this is probably a no-brainer for anyone who has the smog manual) but the desmog diagram -

This thing shows all that should be left when you're done. But it makes so much more sense if you have the original diagram next to it so you can see what Jim "whited out" in the first place. It was a Big discovery for me....... I was like well DUH!"

 

[Eporter]

Jim, thanks for the info, but I'm still confused!

You wrote that the VCV is left alone when desmogging, but I can't figure out why the hose routing changes from stock.

In stock form, two lines from the VCV are T'd together and run to the Distributor cap:

In the desmog diagram, two lines from the VCV are T'd together and run to the Air Cleaner.

Why the change? AND, which lines are swapped? Are no lines changed at the VCV? Are they kept intact to the VCV but their destinations changed?

As in:

Do you swap the stock setup line from the T to the Dist. cap to run from the T to the AC? And do you then swap the stock setup line from the VCV to the AC to run from the VCV to the Dist. cap?

I think I'm getting confused by the factory diagram with the VCV drawn differently than it really is. Imagine that.

When do classes start at The Desmog School?

 

[FJ40Jim]

The difference in the two drawings is courtesy of toyota. You're comparing the schematic w/ the isometric.

Compare the edited vs unedited schematics.

or compare the (poorly) edited service isometric to the original isometric.

The parts dep't isometric is not the best reference for service info.

 

[jfnall]

Sure seems like alot of hoses for a desmogged truck.

I am in the process of a full engine rebuild. tell me if this will work. while everything is out, i am going to strip as much off my 60 as possible. If i have a desmogged carb, headers, electric fuel pump -- what hoses are still required to make the truck run? is my plan of simplifying the motor going to far so that it possibly wont run at all?

has anyone done this and have a pic of it? if so, am on on the right track or barking up the wrong tree?

jeff

 

[Mikesta]

You guys smoke? Damn this stuff has my head spinning. Jim, I'll just send you my carb.

 

[fliphkd778]

I just calculated my gas mileage after I desmogged mine with headers....wow. I was getting around 12-13 before, now I'm down to 6.5. Any suggestions as to why this might be? My timing is set about one BB width on the flywheel advanced past 7*. Plus it backfires on occasion under heavy deceleration

 

[fliphkd778]

I continued tinkering with my dizzy this evening until my spare comes back from a Jim C rebuild. What causes the distributor to advance in the first place? I disconnected all the lines to the dizzy except the ventilation port and it still advances? Is this normal?

 

[fliphkd778]

While I was at it compared my two carbs, one was from a hack job desmog on an '81,(however it ran incredibly well) and my stock one(1986). I noticed that the jets were different between the carbs. The primary in the '81 was a #3 jet, and the primary was only a #1? Then I looked at my '86 and they were both #1's. I couldn't get my truck to start with the '81, so I placed the #1 as a primary, and #3 as secondary. Fired right up. Which combination and placement is better for a desmogged job?

 

[FJ40Jim]

Reid, dunno what jet numbers (or casting #'s) you are looking at...

main jets should be 147 & 200.
Slow jets should be something like a 65 and a 80.

HTH

 

[jys381]

Jim,

Not meaning to hijack too much but what ever happend to that 38 gallon Ford fuel tank project?

TY