My Desmog Thread

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So I have to wonder if desmogging is illegal if the end result is better emissions. For instance if you go to a fuel injection system that vastly improves the em missions of your vehicle and you pass a smog test are you still in the wrong?
 
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Hey guys - question for you. I just finished my desmog with parts from JimC. All has gone fairly smoothly. I'm still awaiting a rebuilt carb and recurved dissy from him, but that may be month more. So in the meantime I'm doing what I can to get this running well.
Started up today, 5degrees F, and ran for about 10 minutes. It was a little rough. I've adjusted the timing. Then I noticed some loud muffler noises and looked down and saw the catalytic converter was red hot!
  1. What is causing the red hot cat? Just way too rich?
  2. Would it be beneficial to remove the cat? (Think I damaged it?)
  3. What is the ideal timing on a desmogged rig? 7 degrees?
  4. Why is it running so rich? Stock carb, with screw still capped from factory. (it was running rich before desmog, but I never noticed a red hot cat)
Thanks for all the help guys!!
Maybe I just need to wait for @FJ40Jim to work his magic on my carb...
 

FJ40Jim

The Cruiser Whisperer
 
 
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I just finished my desmog with parts from JimC.
Started up today, 5degrees F, and ran for about 10 minutes. It was a little rough. I've adjusted the timing. Then I noticed some loud muffler noises and looked down and saw the catalytic converter was red hot!
  1. What is causing the red hot cat? Just way too rich?
  2. Would it be beneficial to remove the cat? (Think I damaged it?)
  3. What is the ideal timing on a desmogged rig? 7 degrees?
  4. Why is it running so rich? Stock carb, with screw still capped from factory.
  1. Too much HC and too much O2. HC could be from running lean. O2 could be from AI or exh leak or lean.
  2. Possibly. A partially melted cat is restrictive and runs hot.
  3. Ideal timing yields highest torque at 2000rpm.
4.stock carb is jetted rich to ensure plenty of CO & HC to feed the fire in the cat. If the float level is up and/or air jets are restricted, it will be even more rich.
 

FJ40Jim

The Cruiser Whisperer
 
 
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So I have to wonder if desmogging is illegal if the end result is better emissions. For instance if you go to a fuel injection system that vastly improves the em missions of your vehicle and you pass a smog test are you still in the wrong?
You are conflating legal & illegal with right & wrong.
It is illegal to modify emission control equipment.
 
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  1. What is causing the red hot cat? Just way too rich?
  2. Would it be beneficial to remove the cat? (Think I damaged it?)
  3. What is the ideal timing on a desmogged rig? 7 degrees?
  4. Why is it running so rich? Stock carb, with screw still capped from factory. (it was running rich before desmog, but I never noticed a red hot cat)
  1. Potentially unburned fuel, if it was running a little rough it could be a misfire.
  2. You probably didn't damage it, up to you if you want to remove, pending state emission laws and your personal feelings about it.
  3. I'll Defer to Jim but yes I believe 7* BTDC
  4. Has the carb ever been rebuilt?
 
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Thanks for the ideas guys! This forum is great.

1 Was running a little rough...
2 Fortunately don't have to worry about emissions. Guess I could take it out and see if it makes any difference.
3 I'll go through the timing again
4. I rebuilt the carb. I'm not positive it's working exactly as it should though. I've got a spare that @FJ40Jim has. Just getting antsy to get it running right
 
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1911

chupacabra
 
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You are conflating legal & illegal with right & wrong.
It is illegal to modify emission control equipment.
"I am free, no matter what rules surround me. If I find them tolerable, I tolerate them; if I find them too obnoxious, I break them. I am free because I know that I alone am morally responsible for everything I do."
-Robert Heinlein
 
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Any advice on breaking the EGR cooler bolts loose? I have purchased an extraction socket set, but still can't seem to get them to budge. I don't want to break off the bolt head.



1917904
 

FJ40Jim

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If the bolt head breaks off, then the EGR cooler can be pried straight away from the block. Once cooler is removed, the broken bolt can be unthreaded w/ a visegrip.
 
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Ah! Thank you Jim, I very much appreciate it sir! After looking at the diagram of the EGR cooler, that thought did cross my mind. It looked like the bolt was only threaded in the block, not the actual cooler, and that it may indeed slide off, if the bolt head broke. Seems like the only case where breaking the bolt head off may be advantageous.
 
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FJ40Jim

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FWIW, the hole in the block is not through into the crankcase, so if the bolt breaks off and can't be removed, it can just be trimmed off flush with the threaded boss. Nothing is gonna leak around the bolt.
 
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Trying to desmog my 1985 FJ60. Both of my VCV valves are bad, as are every other VCV valve I can find on friend's parts rig, or in boxes of parts. So attempting to desmog without VCV valves since they are hard to find. Eventually maybe some electricly operated valves to serve the same function, but for now, EVAP system vented to atmosphere, Evap suction at carb base is plugged. Distributor ventilation hooked directly to air cleaner. Choke breaker hooked up as stock. Decel fuel cut switch is as stock.
Vacuum advance hooked to advancer port at carb base and to outer diaphragm on the distributor. PCV line TEE going to HIC is removed and PCV running to pipe on formerly EGR manifold port. HIC and HAI are not hooked to anything. All other carb ports are plugged. EGR, gone. AIR rail gone. Smog Pump replaced with idler pulley. Not exactly a Jim C approved installation but does anybody see any problems with this plan.
 
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Thanks so much Jim- The other question I had on the above installation....im using one of your rebuilt carbs, but with a stock, not recurved distributor. Ive been going back and forth with running the advance line to the outside or the inside diaphram on the vacuum advance. Initially I had the advance set at 7 degrees, with vac line to the inner primary advance port. It ran better when I ran the advancer line to the outer port. I then tried to advance timing to about 11 degrees and use the outer advance port, which it runs really well with no pinging, but I do get some dieseling on shutdown. Im thinking since I havent had a recurve that the outer secondary port on the dizzy helps limit total advance, but where would initial advance be best set at? What total advance number is best for a desmog?
 
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Has anyone here ever bypassed the air injection but keep the EGR intact? I'm currently in the process of replacing my smog pump with a used one purchased from another MUD member. A slightly leaking power steering pump is probably the culprit that destroyed the old air pump, and now I'm scared to put the used smog pump in and have it explode as well. My plan is to de vein the smog pump, install it, and cap off the air injection system until I can resolve the p/s pump leak but leave the rest of the emissions system intact. My rural county in CA, doesn't require yearly smog testing so there wont be any issue there but I don't want to scrap the whole system in case the rules change, plus the emissions system in my truck was functional up until the smog pump locked up.
 
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Has anyone here ever bypassed the air injection but keep the EGR intact? I'm currently in the process of replacing my smog pump with a used one purchased from another MUD member. A slightly leaking power steering pump is probably the culprit that destroyed the old air pump, and now I'm scared to put the used smog pump in and have it explode as well. My plan is to de vein the smog pump, install it, and cap off the air injection system until I can resolve the p/s pump leak but leave the rest of the emissions system intact. My rural county in CA, doesn't require yearly smog testing so there wont be any issue there but I don't want to scrap the whole system in case the rules change, plus the emissions system in my truck was functional up until the smog pump locked up.

Different vehicle but i've been running the 78 in my 2f like this for a while. When I bought it the smog pump didn't have a belt on it so just removed it. Left the air injection stuff until I could deal with it.
I believe it's fine as long as the check valve in your air injection manifold is working properly?

EGR is still all there
 
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