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It's all good, just jousting in a fun way. It's so bad here in Cali, particularly with the Fords. I would love to install EFI on my Bronco. I know it would pass tail pipe emissions, but they make you pass visual also.
Damn, I feel for you. I dread the day it starts here, or if I retire to an area where testing is strict. We actually went in the opposite direction in 2015. No more inspections! Before that, we had to get annual inspection stickers. It was a joke! Many folks, not me, would just go to a station and buy several stickers for every vehicle they had, then go home and put them on the windshields. Not me, but some folks.
Regardless can you post the test. We need to know where you are failing is it at idle or at high engine RPM''s these limits are not that hard to meet with an engine that is in any sort of reasonable condition.
If it is at idle, the idle air just needs adjusting. If it is at higher RPM the carb is over fueling on the main circuit. Regardless you are running rich and that explains the high HC (hydrocarbons) and CO Carbon Monixde.
So let us know where you failed.
2800ppm HC with a limit of 400ppm
9% CO with a limit of 4%
They tested at idle and at high RPM, and I failed both. I don't know which test the results are from though, they only gave me one
I would back up a bit. Basically you will need to perform a thorough Tune-Up. It's a lot more than just replacing ignition parts, though it will likely need that. A Ford shop manual will be your friend here.
Getting everything back on the beam with the factory specs in the shop manual is how this will work. Voltages, temperatures (thermostat for example) fuel pressure, idle mixture adjustments, jetting ... ignition timing etc etc. This stuff has to be measured and verified. Aftermarket parts look the same as factory approved parts, but there really are differences, and those differences are sometimes really difficult to find when troubleshooting.
The first thing you probably want to do is a cylinder compression test, by the book.
It will never pass smog if the engine needs an overhaul. See where I'm goin' with that?
Do you know if I should have a smog pump on this engine? I'm ordering a manual and plan to do the compression test this weekend. It smells like burnt oil, but it had a bad leak off of the valve cover onto the exhaust so it's hard to tell if that's the only source of smell. It runs and idles super well, with a slight roll to it. Based on other posts it seems like I need to do some carb/intake work.
Things that will drive up the HC would be an over rich carb. Could be jetting, wrong float height, other internal issues. In CA you'd have to go back to the 2bbl, you might be able to make the 4bbl work in TN if they don't see it as tampering. Ditto the manifold if you have a 4bbl manifold. If you have a 2bbl manifold with an adapter I would pull all that and go back to the OEM 2bbl setup.
PCV--if the valve is worn or stuck, you could be getting oil. Oil will drive the HC up, and probably CO. But because you don't have cats I'm not sure what CO standard they are working with. Focus on HC for now.
Clean oil--even if the PCV is working right, if you have fuel contaminated oil due to short trips or overfueling, you will get those fuel fumes sucked back into the engine which will raise HC.
Oil burner--If you are leaving a blue cloud due to rings, you stand little chance of cleaning up HC. Worn valve seals usually make the more visible smoke on start up and under deceleration, when vacuum is the highest. Usually the test doesn't run on deceleration afaik and from what I've seen when getting cars smogged here.
And yes, see post 11 about posting the initial results.
PCV valve is a good point, I have one in the RockAuto cart right now. When it comes to no cats, I'm worried I'm supposed to provide proof of that in order to get the adjusted limits, but I have no emissions sticker or OE door tag.
I also didn't know overfueling could cause this problem, I haven't filled it over 3/4, but could that issue be left over from the previous owner? I didn't think a '78 would have much EGR crap on it.
It only smokes at idle when it's getting a bit hot (it needs some coolant work), but from my understanding this is an early sign of worn rings, but not an indicator of a trash engine.
PCV valve is a good point, I have one in the RockAuto cart right now. When it comes to no cats, I'm worried I'm supposed to provide proof of that in order to get the adjusted limits, but I have no emissions sticker or OE door tag.
I also didn't know overfueling could cause this problem, I haven't filled it over 3/4, but could that issue be left over from the previous owner? I didn't think a '78 would have much EGR crap on it.
It only smokes at idle when it's getting a bit hot (it needs some coolant work), but from my understanding this is an early sign of worn rings, but not an indicator of a trash engine.
If you are smoking at idle due to worn rings you little hope of passing the test. And worn rings is a trash engine and will need a rebuild. Your next step should be a compression test if it is low you will have little hope of passing the test. As you won't be getting complete combustion you will have to lean the engine out so much it will present drivability issues but you will pass the test.
By "overfueling" I meant and should have said "running too rich" due to jetting, powervalve, float height etc.
Overfueling as you mean, overfilling the gas tank, can flood the EVAP system, which could cause it to run rich for a while along with other issues. This is probably not an issue here.
I don't know for a fact that it would have had a "smog pump" but I would assume so.
In those days the catalysts in use required extra oxygen (air) to be injected into the unit to reach the high temperatures necessary to burn off all that gasoline being wasted out the tailpipe.
They (factory/engineers) did a lot of things in that era to meet the federally mandated air pollution requirements that weren't necessarily very good engineering practices from an automotive standpoint. They tended to run hot or on the edge of boiling over, or had reduced power and/or towing capacity, reduced fuel economy and other problems due to de-tuning.
If the engine internally is in reasonably good shape - passes compression test - then you will have to set up the engine the way it was delivered from the factory to get it to pass smog. Ignition timing settings, and carburetor settings/adjustments. Until you know the engine is OK it's just getting off into the weeds. There are a lot of techniques and practices right before the test itself to help nudge things in the direction you want to go, don't worry about that yet.
That carb is too much, jets and all. If you want to use that carb after you pass smog get the Edlebrock Performer 400EGR. It has a removable 2bbl adapter so can reinstall your big holley. Get a Motorcraft 2150 knock off on eBay for less than 100 bucks new.
I've done some checking and it has the Edlebrock Performer 400 intake manifold and the Edlebrock Performer 1406 - 600 CFM 4 barrel carb.
Originally Posted by matthewq4b
Regardless can you post the test. We need to know where you are failing is it at idle or at high engine RPM''s these limits are not that hard to meet with an engine that is in any sort of reasonable condition.
If it is at idle, the idle air just needs adjusting. If it is at higher RPM the carb is over fueling on the main circuit. Regardless you are running rich and that explains the high HC (hydrocarbons) and CO Carbon Monixde.
So let us know where you failed.
It failed both at idle and at 2500 RPM
Originally Posted by 85e150
Things that will drive up the HC would be an over rich carb. Could be jetting, wrong float height, other internal issues. In CA you'd have to go back to the 2bbl, you might be able to make the 4bbl work in TN if they don't see it as tampering. Ditto the manifold if you have a 4bbl manifold. If you have a 2bbl manifold with an adapter I would pull all that and go back to the OEM 2bbl setup.
PCV--if the valve is worn or stuck, you could be getting oil. Oil will drive the HC up, and probably CO. But because you don't have cats I'm not sure what CO standard they are working with. Focus on HC for now.
Clean oil--even if the PCV is working right, if you have fuel contaminated oil due to short trips or overfueling, you will get those fuel fumes sucked back into the engine which will raise HC.
Oil burner--If you are leaving a blue cloud due to rings, you stand little chance of cleaning up HC. Worn valve seals usually make the more visible smoke on start up and under deceleration, when vacuum is the highest. Usually the test doesn't run on deceleration afaik and from what I've seen when getting cars smogged here.
And yes, see post 11 about posting the initial results.
I've replaced the PCV, and it only smokes lightly when it gets too hot, no smoking at idle or under normal conditions
Originally Posted by Tedster9
I don't know for a fact that it would have had a "smog pump" but I would assume so.
In those days the catalysts in use required extra oxygen (air) to be injected into the unit to reach the high temperatures necessary to burn off all that gasoline being wasted out the tailpipe.
They (factory/engineers) did a lot of things in that era to meet the federally mandated air pollution requirements that weren't necessarily very good engineering practices from an automotive standpoint. They tended to run hot or on the edge of boiling over, or had reduced power and/or towing capacity, reduced fuel economy and other problems due to de-tuning.
If the engine internally is in reasonably good shape - passes compression test - then you will have to set up the engine the way it was delivered from the factory to get it to pass smog. Ignition timing settings, and carburetor settings/adjustments. Until you know the engine is OK it's just getting off into the weeds. There are a lot of techniques and practices right before the test itself to help nudge things in the direction you want to go, don't worry about that yet.
I've done some checking and this truck does not have an EGR system of any kind. It has the PCV that hoses into the carb, a vacuum line from brake booster to intake manifold, and a vacuum line from the spark adjuster on the distributor to the carb. No where else does it have a vacuum line, and this is the stock setup. In '78 if you got it without emissions, it excluded the catalytic converters as well as the EGR system.
I was my understanding that F250's and above were non-catalyst engines, meaning because they were work trucks, in 1979 they did not have to meet emissions standards.
I've seen this on F-250 and F-350 valve covers
I was my understanding that F250's and above were non-catalyst engines, meaning because they were work trucks, in 1979 they did not have to meet emissions standards.
I've seen this on F-250 and F-350 valve covers
Ah thanks for the picture, my truck doesn't have factory covers so I have no emissions plate. Thankfully in TN they don't do an engine inspection, but they've told me I still have to pass the tailpipe test at idle and 3000 RPM. I know they didn't have to be compliant back in the day, but I'm not sure how to convince anyone of that fact. I've gotten antique plates for it while I fix it up, maybe I can show them this picture as proof that some stock trucks came like this.
