Desmog Help!

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Joined
Sep 5, 2002
Threads
42
Messages
1,689
Location
Bend, Oregon
Howdy all,
I have a '77 FJ55 that I just dropped an '81 FJ40 2F engine into. The donor 2F from the FJ40 had already been 'desmogged' and I am more familiar with older F engines and decided to keep this engine desmogged but want to make sure I do it the 'right' way. That's where you all come in, yet again. I have been using the 'search' method and have been educating myself a bit on the process but each thread/build I read is slightly different due to different years/setups I imagine. I was hoping to get some specific advice about my set up from everyone else. Please post up if you have advice.

The donor engine is in. The air rail has been capped off. The entire EGR setup has been removed. The smog pump has been disconnected along with hoses. The carb and dist. had been sent to Jim C. for a rebuild/desmog/bionification! I removed the VCV dealio. I have plugged some of the vacuum ports but I think I still need to disconnect more vacuum lines and plug more ports.


1. Anyone know which vacuum ports to plug, which ones to connect/leave?

2. Is there a 'computer' that needs to be disconnected to make this all work properly?

3. Anyone see anything I may be missing? Or that I did incorrectly?

I'll throw up some pics of what I have done thus far...

Pic 1- Some of the vacuum lines and accesories I am still not sure I should remove...
Pic 2- Can I remove this???
Pic 3- I believe I should be capping this port on the intake manifold, right?

Here is also a link to my other desmog thread in the 40/55 section...
https://forum.ih8mud.com/showthread.php?t=176281
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On the other side of the engine...

When I recieved my carb and dist. back from Jim C. they each had one port capped off. I assumed those were to be left as is. I connected the dist to the carb using vac line. I plugged the vac line into the remaining open port on the base of the carb and one of the ports on the dist. cap. This left me with two open ports still on the dist cap. One I believe I was supposed to cap off (larger one)-which I did. The other (smaller one) I believe I read it should have fresh/clean air. Instead of tapping into the air filter assembly I 'borrowed' an idea from Guyute (on Cascade Cruiser forum/Mud) about fabbing a seperate filter for it. So I did. Seems it would work well and looks slick.

Do I need to vent the charcoal canister also?

Here are some pics...
Pic 1- Pinky is pointing to larger port I capped off and the other finger is pointing to the port I vented seperately.
Pic 2- All the stuff I used for the seperate vac line and some vac lines/hoses I installed.
Pic 3- I connected the filter to the vac line and dist. and then mounted it to the radiator with a little something I found hiding in the shop.
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As well, here are some of the PO mods to the air filter assembly. Are these all supposed to be plugged? Anything else need to be plugged?

Also, there seems to be a vacuum-actuated valve on the end of the air filter housing (toward the grill/front of vehicle). There is no vac line hooked up to this valve which means it is closed to fresh air and currently sucks in 'engine bay' air from the bottom of the filter housing. Should I dismantle/remove the valve and pull fresh air all the time, leave it as is, or ???

Thanks for any help folks!
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Hey Lucy, questions listed in order from your first post. Hopefully, I can help without giving you too much false info.;p

  1. Not Sure
  2. Computer... AFAIK no, the computer should be fine left alone.
  3. Is your PCV hooked up? What is the loose hose with the VTV inline, in the first pics?
  4. Try using this desmog guide, I know its not the same year but it might help http://www.ih8mud.com/tech/smog/72706FJ60desmog.jpg
  5. Not sure
  6. I think that bolt just holds the shield in place, does the hole go all the way through?
  7. Pulling fresh air all the time will be fine, except in colder climates you could ice the carb.
 
I found some details about a bunch of the smog-related stuff on the driver's side of the engine bay. My freakin' Haynes manual ended up being the most help-strange. It had specific details for my rig's emissions as well as good diagrams, info/explanations, pictures, etc. about each part. Glad I found that.

I ended up removing the Vacuum Surge Tank and both VSV's (they were mounted to the top of the Vacuum Surge Tank) as well as all the vac hoses that were connected to them. I also removed the VCV's that were mounted on top of the thermo. housing. This left me with a few more vac ports to plug. I used some small rubber/plastic vac plugs to cap off the diaphram on the carb, the BVSV connected to the thermo. housing, and then I set up another mini-filter to the charcoal canister.

I then took it for a spin and it did seem a bit better. I think I have other issues I need to decipher now, but that is another thread.

Please post up advice/ideas still if you have any. Suggestions always welcome.

Pic 1- Here is the Vacuum Surge Tank, VSV's (bottom of pic) assorted vac lines, and I am pointing to the end of the charcoal canister I vented.
Pic 2- Pointing to the VCV's I wound up removing.
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Hey Lucy, questions listed in order from your first post. Hopefully, I can help without giving you too much false info.;p

  1. Not Sure
  2. Computer... AFAIK no, the computer should be fine left alone.
  3. Is your PCV hooked up? What is the loose hose with the VTV inline, in the first pics?
  4. Try using this desmog guide, I know its not the same year but it might help http://www.ih8mud.com/tech/smog/72706FJ60desmog.jpg
  5. Not sure
  6. I think that bolt just holds the shield in place, does the hole go all the way through?
  7. Pulling fresh air all the time will be fine, except in colder climates you could ice the carb.

Howdy Mike,

Thanks for the response/answers. I think I may have figured out a bit more of it. I'll wait until others chime in. I couldn't find the emission computer even with the Hanes manual stating where it should be as well as having a picture of what it looks like. I plan on double-checking my OEM manual to see if it shows where to find it. Oh, and that brass plug did cap a hole that went all the way through my intake. That spot had been where some vac lines from the VSV hooked up. Anyway, that's all plugged for now.

I am still researching. Let me know if you have any more ideas.

Thanks again, Carlos.
 
Well, we have had a few cold mornings around here and the truck has been running rough again.

The engine sputters and I have weak acceleration in 3rd/4th gear. I am guessing vacuum leaks/exhaust leak at the header. I still need to remove the emissions computer (I think...) and I think I know where to find it. It sounds like it may be hiding behind the driver side kick panel. I am going to look there and probably disconnect it to see if that helps at all. I guess I should re-tourque head bolts, carb bolts, intake manifold/header bolts, etc. I should probably re-adjust the valves as well.

It occurred to me that my newer long-range fuel tank may be messing with things as well. I have a hissing/ringing sound occassionally from the gas tank after I stop driving. It has the OEM cap that should relieve some pressure but may not be working properly. Does any of this sound like a blocked charcoal canister or anything. Any ideas or am I nuts?

Thanks for any advice folks. Still researching...
 
When Jim C rebuilt my 78's carb (origianally CA emissions) here's what he instructed me to do:

1. keep the dissy advance
2. keep the Outer Vent Control Valve solenoid on the charcoal canister
3. keep the VCV that captures the fumes from the charcoal cannister and directs it to the carb
3. disconnect the dam emissions computer

The two nipples on the dizzy:
The small one connects to the air cleaner directly above the dizzy creating a vacuum to keep moisture out
The large one connects to a nipple on the firewall and directs "dry" cabin air into the dizzy instead of dust/water.


The EGR port on the carb gets connected to the blue BVSV on the water pump housing and then the VCV to recapture the fumes from the charcoal canister.

The Advance port on the carb goes to the dizzy advance

The Choke Breaker is disconnected.

The Throttle Positioner is connected directly to the intake manifold w/o the VTV (blue/white)

Here's a photo

Let me know if you want additional photos - I can send them via PM or e-mail.
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Thanks Ming!

I am going to go and try this ASAP and I'll let folks know how it goes. I already removed some of the items but I can certainly slap 'em back on. Jim rebuilt my carb and re-curved my dist. with a desmog in mind but I did not receive any further 'instructions' and have been kinda' wingin' it.
 
FWIW - with the set-up prescribed by Jim C I passed Illinois emissions although I had to lean the carb a bit. Just goes to show that all the added on emissions junk from the 70's was minimally effective.

Lucy, the emissions computer is located near the clutch pedal on the firewall near the hood release handle. Just unplug the connector.
 
So I just spent some time under the hood trying to make some sense of this all. I made some progress. I have used the reference from Ming as a guide and have followed up each of his instructions/questions with an answer and sometimes a bunch more questions of my own. :)

Please give it a read and let me now if you have any other advice/answers. Thanks again everybody.


When Jim C rebuilt my 78's carb (origianally CA emissions) here's what he instructed me to do:

---Thanks again, MING. I also have had my carb and dist. tweaked by Jim C. Here are some of the steps I have taken and some more questions I now have...

1. keep the dissy advance ---DONE. My dist. is an '81 and has two ports coming from the vac advance. Jim C. sent it back with one port plugged with a red cap. I left that assuming I was suppossed to use the other port. Other port I connected to the base of the carb. There are two ports at the base of the carb and again Jim C. plugged one with a red cap so I used the other. I can't seem to figure out what the those ports on the base of the carb do or are called? Ideas???

2. keep the Outer Vent Control Valve solenoid on the charcoal canister ---Uh, I am not sure what/where this is. My manual goes to '77, is it a '78 thing or??? Help?

3. keep the VCV that captures the fumes from the charcoal cannister and directs it to the carb ---Hmm, do you mean VSV? I am trying to figure this one out also. Any clarification/better pics would help. I only know enough to be dangerous. From the pic and one of the manuals it appears you kept one of the VSV's on the fire wall. I think you have a vac line running from the VSV to the air cleaner and the other end of the VSV goes??? My '77 has some slightly different looking VSV's- then again I may be confused. Anyway, the VSV's where orig. mounted on top of a Vacuum Surge Tank- do I keep this? Also, where the vac line appears to tap into the air filter (from the VSV on the fender) are three ports total. Well, mine have been welded shut by a PO apparently. Anyone have any advice on this?

3. disconnect the dam emissions computer ---DONE. Mine looked slightly different than the one pictured in my manual but I am fairly certain I unplugged the right thing. I hope.

The two nipples on the dizzy:
The small one connects to the air cleaner directly above the dizzy creating a vacuum to keep moisture out ---DONE.

The large one connects to a nipple on the firewall and directs "dry" cabin air into the dizzy instead of dust/water. ---Almost DONE. I have it unplugged for now but plan on using the 'bling' mini filter idea there. I am not sure where it should meet with the firewall so someone else recommended this idea. I think it should work well and look slick. And its cheap.


The EGR port on the carb gets connected to the blue BVSV on the water pump housing and then the VCV to recapture the fumes from the charcoal canister. ---Where is the EGR port on the carb? Help?

The Advance port on the carb goes to the dizzy advance ---This may be done but I am not exactly sure. I assumed the not-plugged ports on the carb and dist advance should connect but that may be inncorrect.

The Choke Breaker is disconnected. ---The Choke Breaker Linkage? Really? Does this diable the choke? Or am I confused again?

The Throttle Positioner is connected directly to the intake manifold w/o the VTV (blue/white) ---Hmm, right now I have the TP capped. That is probably bad, eh? Where should this tap into the intake? on the left/top?Picture? :)

---OH SO MANY QUESTIONS!!! Thank you everyone for all the advice and help. I am so close.

Here's a photo

Let me know if you want additional photos - I can send them via PM or e-mail.
 
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Lucy,

Hopefully this will expand my first post on the desmog:

Jim C is more than willing to lead you through the desmog - he answered numerous PM on what to do for your specific year/configuration so you may want to go direct to the source.

My 55's are both CA emission versions of the 2F which means that they have unique carbs and dizzy. My dizzy only has an advance port where as your Federal dizzy has an advance port and a retard port. Jim plugged the retard port for you. My original CA emissions carb had three ports on the base - when Jim rebuilt and desmogged my carb I lost one of the ports. I also added some tags to the existing carb ports and asked Jim to indicate where each should go, which he did.

I would supliment your Haynes manual w/ an OEM 2F and emissions manual. The OEM manuals are well worth the $.

As far as your questions:

Outer Vent Control Valve - is/was located on top of the charcoal canister and switches the patch of fuel fumes to either the charcoal canister or to the carb (large port near the float bowl). It's actuated when you turn the ignition on. It has a two pronged electrical connector.

VCV vs. VSV - The OEM emissions manual defines the large solenoid "brick" on the DS firewall as the Vacuum Switching Valve. This is the switch that the "emissions computer" actuates. The VCV or Vacuum Control Valve is the round vacuum actuated valve that opens a path from the charcoal canister to the large port on the carb base. It's actuated by pulling vacuum at the EGR port on the carb then the blue BVSV valve in the thermostat housing opening (when it reaches temp) and is exhausted into the air cleaner. Fuel path is from charcoal canister to carb insulator while the activation path is from the EGR port vacuum source pulling clean air from the air cleaner.

Carb Ports - My OEM CA carb has only and EGR and Throttle Positioning Port while your OEM Fed carb has an extra port for the dizzy advance. Depending on how Jim rebuilt your carb you may now only have 2 ports - I don't know. Here's where the OEM emission manual is real handy.

Choke Breaker - my mistake. The OEM manual's Jinglish uses both interchangably.

I hope this helps a bit - I can take some photos if it would help more.
 
Ming- you sir, are a good egg. Thanks for taking the time to answer all of my questions as well as explain what all the emissions crap is supposed to do. I appreciate your time and detail. This is all begining to gel in my empty head. :)

I actually have a few of the OEM manuals except for the emissions one. SOR wants $50 for my year emissions manual (...the most expensive year of all the ones they sell! WTF!) so I have been trying to source one elsewhere-any ideas? The Haynes manual usually sits on the shelf buried under some parts. I have been completely shocked by it for this particular application- it has great diagrams/pictures and explanations of the smog stuff. Granted, I still don't trust the Hanes manual solely but it comes in handy once in a while. The OEM manuals of course rock. As for Jim C., I should PM/email him again. I know he can help me.

Still plugging away at this, gotta drive the damn Subaru to work again. I'll keep ya'all posted. Thanks again Ming. OINK! OINK!
 
Well, no response from Jim C. He must not like me. I'll keep trying.

1. Can someone take a pic of their charcoal canister and the Outer Vent Control Valve (OVCV) solenoid that is supposedly attached to the charcoal canister? I can't seem to locate one in my rig.

I guess any pics of 'properly' desmogged engines would help. I am using the desmog diagram found in Tech and the advice from Ming. Some of the items in the engine bay are attached properly but not others. I am still confused.
(But maybe that is inevitable.)
 
1. So, the Throttle Positioner (Choke Breaker) is connected directly to the intake manifold without the VTV (blue/white)? Right? Where/how on the intake manifold does the vac line connect. Any pics?

2. Where is the EGR port on the carb? Pics?

Better yet, does anybody have an emissions manual they would like to copy/sell/loan me for this process? Where else can I purchase an OEM emissions manual from beside Ebay and SOR? Do an of the Mud vendors carry OEM manuals? Just curious, I would rather support them.

Thanks again everybody.
 
Still waiting for the the OEM emissions manual, but for now...

I started the rig up after sitting for a week or so and noticed both a bit of black smoke as well as fluid spitting form the tailpipe. That kinda alarmed me a bit. She was also running a little rough when I last parked her in the garage and sounded the same today. Valves were also making more noise then when I first finished the install a month ago or so.

So, I removed the air filter assembly and re-tightened the carb. valvetrain, some of the intake/header, and head bolts. I also removed the plug I capped off the intake with and replaced it with the original fitting and ran a vac line from it to the TP (Throttle Positioner) on the carb as others have suggested. I also re-adjusted the valves, I found a few of the valves were more loose then they should have been. After I adjusted them and replaced all the hoses and the air filter I fired her up. The engine actually sounds better. I noticed a little white smoke but no black smoke really. The rattle in the valvetrain is basically gone-singer sewing machine like. I believe my EGR port may be plugged already. I took her for spin and she seemed more peppy, better reponse in the higher gears/speeds. I guess there seems to be a vibration somewhere that I need to track down-but that is another thread...

And pics...
Pic 1- Gunk from tailpipe. Fluid on floor and a bit of black smoke. (Black stains on plywood are actually from oil from another use)
Pic 2- Vac line from TP to intake, other vac. port capped. (Before I had the port on the intake plugged and the TP capped, Doh!)
Pic 3- Is this the EGR port on the carb? If so, Jim C. blocked mine off for me.

Any other advice?
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I'm glad i ran into this thread. I am in the middle of trying to figure this out myself. You seem to be doing a better job than I. Jim C. did both my carb and dissy for a desmog. Your photos are a big help, please keep them coming. I have the same engine...81 fj-40 2F. Between both of us maybe we can compile some comprehensive photos of what needs to be done for our year engine.
 
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