1980 2F de-smog specific questions

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
I've read all of the de-smog threads I could find in the FAQ and by searching; all helped me immensely but I have a few issues on mine that I didn't see covered before.

#1, my distributor advance pot has two vacuum lines that both disappear into the bag of snakes (giant vacuum line manifold bolted to the thermostat mount). I know that one of them needs to go to vacuum at the base of the carb, but which one, and what about the other line? Here is a photo of the dizzy and vacuum advance w/ two lines:



#2, hoping to catch Jim C.'s attention here, since I bought his de-smog kit: Jim, in your email you mentioned two thermostat housing plugs; indeed there are two in the kit, but there are three vacuum switches on my thermostat housing - a pink one, a blue one, and a violet one. All three have two vacuum hoses each that disappear into the giant manifold and bag o' snakes. Can I get rid of all three? If not, which one remains? Here is a photo of the thermostat housing; the pink vacuum switch is on top and the blue and violet ones are low on the driver's side:



#3, when I took off the air injection rail, there are two (temperature?) senders in the top of the head. The one in the middle of the head, right across from the carb, was not connected to any wire and has not been for some time (terminal is dark and dirty). I can't find any obvious wire that goes there - anyone know what this sensor is supposed to be connected to? Here is a photo of it, in the bottom center of the picture:



#4 and final, What do I do with the metal line that runs from the charcoal canister on the passenger side all the way around to some valve or pot on the air injection system? I hope I can take it off and just plug the nipple on the charcoal canister; seems logical but I thought I 'd better check first.

Any and all help mucho appreciated!
 
Last edited:

FJ40Jim

The Cruiser Whisperer
 
 
Joined
Sep 26, 2003
Messages
10,578
Location
Lancaster, Ohio, USA
#1, my distributor advance pot has two vacuum lines that both disappear into the bag of snakes (giant vacuum line manifold bolted to the thermostat mount). I know that one of them needs to go to vacuum at the base of the carb, but which one, and what about the other line? Here is a photo of the dizzy and vacuum advance w/ two lines:

The Desmog Schematic shows which dissy fitting is usually used for vac advance.

#2, hoping to catch Jim C.'s attention here, since I bought his de-smog kit: Jim, in your email you mentioned two thermostat housing plugs; indeed there are two in the kit, but there are three vacuum switches on my thermostat housing - a pink one, a blue one, and a violet one. All three have two vacuum hoses each that disappear into the giant manifold and bag o' snakes. Can I get rid of all three? If not, which one remains? Here is a photo of the thermostat housing; the pink vacuum switch is on top and the blue and violet ones are low on the driver's side:

The Desmog Schematic shows that one BVSV remains to drive the evap purge.
In this case, the bottom one is broken, so use the middle one. Delete the top & bottom BVSV.

#3, when I took off the air injection rail, there are two (temperature?) senders in the top of the head. The one in the middle of the head, right across from the carb, was not connected to any wire and has not been for some time (terminal is dark and dirty). I can't find any obvious wire that goes there - anyone know what this sensor is supposed to be connected to? Here is a photo of it, in the bottom center of the picture:

That is the engine temp sensor for the emissions computer. It was not used after 1978, so the head on the engine has been replaced w/ an earlier one and the sensor was left in place to plug the hole.

#4 and final, What do I do with the metal line that runs from the charcoal canister on the passenger side all the way around to some valve or pot on the air injection system? I hope I can take it off and just plug the nipple on the charcoal canister; seems logical but I thought I 'd better check first.
The Desmog Schematic shows the canister purge VCV remains in place, driven by ported vac through the BVSV.
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
The Desmog Schematic shows which dissy fitting is usually used for vac advance.



The Desmog Schematic shows that one BVSV remains to drive the evap purge.
In this case, the bottom one is broken, so use the middle one. Delete the top & bottom BVSV.



That is the engine temp sensor for the emissions computer. It was not used after 1978, so the head on the engine has been replaced w/ an earlier one and the sensor was left in place to plug the hole.



The Desmog Schematic shows the canister purge VCV remains in place, driven by ported vac through the BVSV.
Thanks Jim, I am plotting out a large copy of the Sesmog Schematic as we speak, and will study it carefully.



what is the production date of your rig?
12/79 build date.
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
Joined
Aug 13, 2004
Messages
5,802
Location
Normandy Park Wa. ........now in San Diego Ca.
#1 If parting with what you remove....I am in need of a few parts

As you have done...remove air rail and plug. Also there is a nipple that stickes up fom the intake manifold infront ot the carb.-- remove...the hose (save I need) and remove the nipple and plug or just plug nipple... you can remove the ASV and associated parts from the drivers inner fender if desired. You will need to keep Smog pump or buy an aftermarket idler...
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
Though I don't think I'll ever need them again, I hate to get rid of the smog parts "just in case". I'm going to be moving to different state in a couple of years, and though it would be legal there right now I'm worried they might pass a new law between now and then and possibly not be grandfathered in since I'm not there yet, if that makes sense. If I decide otherwise you guys can have the stuff for free.
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
OK, all the air injection and EGR stuff is off and it's running good, but I'm still working on re-plumbing the remaining vacuum lines directly instead of using the stock bag o' snakes manifolds. A few more questions for Jim C. or anyone who knows:

1. My carb has two diaphragm pots on the driver's side rear, one at the top and another below it. This photo is not the greatest but you can see the bottom pot behind the brake master cylinder, near the bottom center of the picture:



The top one must be the choke breaker/throttle positioner, the bottom one must be the "Choke Opener" in the [URL="http://www.ih8mud.com/tech/smog/72706FJ60desmog.jpg"]Desmog Schematic , correct? The Desmog Schematic shows that the vacuum line for the Choke Opener just goes to the air cleaner housing, no vacuum? Just making sure - what actuates the Choke Opener if it's just connected to atmospheric pressure in the air cleaner?

2. This rectangular thing in the center of the photo:



has a vacuum line that goes straight to the air cleaner housing, again no vacuum just atmospheric pressure in the air cleaner housing. Should I leave it, or cap it off?

3. There are three vacuum ports at the carb base, on the engine side:



One of these (the front-most one, the farthest right one in the photo) is now where the distributor advance is connected. Does it matter which of the other two I use to connect the Choke Breaker? Since I have an 11/79 build truck, I gather from other desmog threads that I could also hook up the choke breaker to one of the three vacuum ports at the air horn at the top of the carb. I have three vacuum ports in my air horn:



Does it matter which one to use for the choke breaker, or is it preferable to use one at the carb base?

4. The Desmog Schematic shows the "Gas Filter" on the intake manifold with one vacuum line going to the VCV for the dizzy, but the other line plugged off, is that correct? Right now, both lines disappear into the bag o' snakes manifold.

Thanks again for your help, and sorry to bug you with so many questions.




[/URL]
 
Last edited:

FJ40Jim

The Cruiser Whisperer
 
 
Joined
Sep 26, 2003
Messages
10,578
Location
Lancaster, Ohio, USA
Remove the spaghetti pipe assembly, then just install the needed vac hoses.

The choke breaker (upper pot) connects to the center top fitting on front of carb. Other 2 frt fittings are capped.

The choke opener (lower pot) is not needed. Leave it open to atmosphere, or remove it, or connect it to the air cleaner.

Rectangle box is the HIC. Connect to air cleaner on top, and a port located on carb insulator base at the bottom. Note that it is larger than standard vac hose.

Check the other desmog drawing to see which fittings at carb base go where.
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
Thanks again Jim! Any comment on the "Fuel Filter" on the intake manifold hose routing? The Desmog Schematic shows only one line going to the dizzy VCV, and the other in a short loop (plugged off?).
 

FJ40Jim

The Cruiser Whisperer
 
 
Joined
Sep 26, 2003
Messages
10,578
Location
Lancaster, Ohio, USA
Thanks again Jim! Any comment on the "Fuel Filter" on the intake manifold hose routing?
It is an Engrish translation for "air vacuum filter". Air is a gas, therefore the vacuum fitting w/ a small filter, is a gas filter. Not fuel, not gasoline.

The Desmog Schematic shows only one line going to the dizzy VCV, and the other in a short loop (plugged off?).
Correct.
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
Final note: Desmog is now complete, hopefully to a high standard acceptable by Jim C. ! :) The only thing I haven't done yet is to replace the two non-used BVSV's on the thermostat housing with plugs, which I'm going to wait and do next time I have to drain any coolant.

I'm really happy with the results; exhaust temp (as measured through the floorboards/e-brake lever) is way down, and it accelerates and decelerates much smoother. Before the desmog, letting off the throttle was like throwing out an anchor. I'll be curious to see if there's any difference in fuel economy, I was getting 10.5-11 mpg previously. Either the smog stuff was not working well, or the PO had something hooked up wrong, but everything looked stock and unmolested as far as I could tell.

Big thanks to Jim C. of TLC Performance for the parts, instructions, and hand-holding and for the previous threads, diagrams, and resources on MUD. :cheers:
 

1911

chupacabra
 
Joined
Aug 11, 2006
Messages
5,481
Location
Parker County, Texas
post de-smog gas mileage

Like I said before, the de-smog has made my cruiser run much better. I've gained another 10 mph in comfortable highway speed, and on my first two complete new tanks of gas post de-smog I'm averaging 13.3 mpg, which is 21% better than my best previous mileage of 11 mpg. No more cooking my right foot on the highway either. :clap:
 
Joined
Jul 21, 2006
Messages
158
Location
Fayetteville, AR
Where did you end up getting the plugs for the BVSV's on the thermostat housing?

The previous owner of mine did a de-smog and one of the BVSV's is leaking coolant. Thanks.
 
Top Bottom