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I have an 86 f250 with the 460, recently my state changed its emissions laws so it has to pass. It passed everything but co emissions. The previous owner deleted the emissions system from the truck, and im having a hard time finding everything it needs to pass.
I was wondering if anyone had installed catalytic converters on a factory catless system and if that would work to reduce the co emissions and get it to pass, I'm only allowed to produce 3.5ppm and it is currently making 11ppm.
Unfortunately, salvage yards can't sell catalytic converters, so you'll have to go to an exhaust shop and get an aftermarket one if your truck originally had one.
What rpm did it fail at? A cat may help it, but careful carb tuning may help it also. Your air to fuel ratio is too rich at whatever rpm it failed at. If it failed at idle, a simple idle mixture adjustment may solve it.
P.S. What state do you live in?
Unfortunately, salvage yards can't sell catalytic converters, so you'll have to go to an exhaust shop and get an aftermarket one if your truck originally had one.
I do not have any of the factory parts, the guy I got the truck from pulled the engine and "rebuilt" it. He replaced the intake and carb with aftermarket parts, as well as deleted the entire emissions system. The only readon the smog bracket is still there is for the alternator.
Factory the truck is catless, just thinking of ideas so I don't have to send this one to the junk yard
Google search say its estimated to reduce CO by 90%, so there is that(supply your own grain of salt there).
Additionally you could research/watch YouTube videos for the smog deletes and reverse engineer what is needed. When I looked up to find a system cross sheet I did come across a lot of thumb nails for the smog delete for the 86 460's.
Lastly, what ever route you decide I would piece mail the repairs. If there is no guarantee that even a intact system would pass then you need to do the waiver two -step and spend the $250-350 every cycle. I'm in MD and have always had this to deal with, was good to sniff out the hack shops when pricing out emissions repairs they always seemed to be the minimal amount for the waiver. Surprised it doesn't qualify for a waiver on age. Can you retag as a work around? I was able to get farm tags for a truck to remove the emissions requirement.
Sorry to only offer a series of work arounds vs actually fixing the problem, but that seems to be the best you can hope for when dealing with the state sometimes.
What rpm did it fail at? A cat may help it, but careful carb tuning may help it also. Your air to fuel ratio is too rich at whatever rpm it failed at. If it failed at idle, a simple idle mixture adjustment may solve it.
P.S. What state do you live in?
the test doesn't say what ram, though I'm guessing both. Definitely runs extremely rich at idle, state is utah. I do have a kit coming in with the rods springs and jets, hopefully a few swaps should bring it down some
I do have a kit coming in with the rods springs and jets, hopefully a few swaps should bring it down some
Before you swap parts and mess around with it, see if you can't adjust it first. More than one person has screwed themselves by shooting the 'parts cannon' at their trucks and made a bigger mess. If it's running extremely rich at idle, let's see if you can't address that first, without swapping in new parts (which may solve nothing). Dollars-to-doughnuts if you lean out the idle mixture you may solve all of your problems (and will have spent little-to-nothing).
x2 on addressing the rich condition at idle. You should get a vacuum gauge to set your idle mixture screws. Sometimes auto parts stores will rent them.
If the truck was cat less from the factory then you should be able to get it to pass with out one.
The air pump only pumps air into the EXH system and I believe it just thins out the readings.
I was able to get a 75 v8 can, no cat from factory, removed air pump and v2 Holley carb to pass smog back in the day.
Get the motor up to temp set the timing to factory or maybe 2* retard.
Adjust the idle mix screws lean. You adjust for best idle or vacuum then turn them in 1/4 turn each.
With the timing and idle mix set like that it will run like crap but that is ok as long as it will pass smog then go back and adjust for best running.
Oh I also changed the oil just before going as dirty oil can raise the CO reading.
Dave ----
Took it back again and the test aborted due to it backfiring, I have it as close to 14 on an afr gauge I can get it. Might be time to pull the motor and scrap the body
Took it back again and the test aborted due to it backfiring, I have it as close to 14 on an afr gauge I can get it. Might be time to pull the motor and scrap the body
Its not the body that is bad but the motor so why scrap the body?
What did you do before you took it back for a recheck?
Retard the timing, kick the idle speed up just a little, lean out the carb, change the oil, etc.?
When did it back fire? Did it back fire when driving it to the test site?
We need more info
Dave ----
Brought the idle screws in as far as it could handle and set the timing to about 6 degrees before tdc, I didn't change the oil as it hasn't been ran more than 50 miles on it. Didn't backfire while I was driving it, but revving it did cause it to backfire
Why did you decide on 6 degrees BTDC? Retarding the timing at idle can help it pass, but only because it slows the idle down so bad, you have to open the carb throttle stop adjustment screw some to get the idle back where it should be. This allows more air into the carb at idle. But it's all experimentation. If something you did is causing the backfiring, I would undo it.
Why did you decide on 6 degrees BTDC? Retarding the timing at idle can help it pass, but only because it slows the idle down so bad, you have to open the carb throttle stop adjustment screw some to get the idle back where it should be. This allows more air into the carb at idle. But it's all experimentation. If something you did is causing the backfiring, I would undo it.
True he should have set it to 6 BTDC, thing factory, reset the idle speed back to factory and turned the idle mix screws in maybe 1/4 each.
Not knowing if he turned up the idle speed after the timing adjustment and turning the mix screws in what sounds like a lot, is why the back fire, lean and retard timing.
Little changes with the mix screws should change the CO a lot at idle.
Now if they also check smog at say 2500 RPM and level is high then the main jets and power valve if you have one, would need adjusting to bring the smog levels in to pass.
Just to the left what is that? Would that be what RPM it was checked at?
Dave -----
