Help needed passing Emissions!

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gliderider06

gliderider06

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Hi folks! It's that time again when I need to get my 87 Ramcharger inspected again. It failed emissions testing again. Last year my Hc were through the roof and this year it's the Co readings. It is a stock rebuild 88-318 with 5,800 on the motor. I have an edelbrock 1406, (3,500mi on new carb) mounted atop a stock cast iron spread bore intake using an adapter. Airfilter is a stock housing and dual snorkels, with fresh air and K&N filter.
HEI ignition converted, stock distributor. Timing is at 18* initial, 34* total. New wires, plugs, cap, rotor, distributor. (Less than 1,000 miles on all of it.)
Exhaust is duals through stock manifolds, 2 catalytic converters and turbo muffs.
I am running 15-w40 diesel oil and it has about 1,500 miles on it. I plan on changing it again before re inspection just for sake of argument.
Any suggestions? I thought about, since I have new on another engine, an MSD distributor with vacuum advance and possibly adding an MSD 6A Box to it or the HEI setup currently on the truck.
If I continue to fail, I have to spend $200.00 in emissions related repairs in order to apply for a waiver, BUT it has to be within 30 days of the inspection failure. So, all the stuff already done in May does not count. The new engine, carb and ignition system means nothing.
Ideas?!
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Where is the timing set and what did you do to adjust the carb?

Generally make certain "everything" is in good shape, good plug wires and cap, plugs, do a compression / leak down and make sure the engine in good shape. Any evidence of leaking valve seals? Oil "puff" on startup?

Make sure float level on carb is not "high" and is dripping / dribbling/ "pullover" gas into throats. You can see by LOOKING at idle, down into the throats

Go look up some of the 74 specs. Set timing as retarded as it will run, TDC and make sure YOU DO NOT have a performance curve in the dist. Maybe just go buy a stock junkyard dist and get it "up to spec"
NO vacuum advance at idle, again, you want RETARDED and SSSSSLLLLLLLllllllooooowwww advance curve

Make sure it has a "hot" Tstat. Factory are 190-195-ish don't run a 180 and GET IT CLEAR UP TO TEMP before testing

Carb. Set idle "a bit" high and peak the idle mixture screws with a vacuum gauge, then "bump" them to the lean side (CW) just a tiny bit
 
Lean your fuel mixture a bit if you can. High HC and CO can come from too much fuel. You may want or have to back off the timing a bit as well.
 
The mere fact that any state expects an 87 anything to pass smog is bordering on preposterous. Can you buy replacement parts at the stealership? Uh, no............

When did Ma go with TB injection on those? Must have been close............
 
royslead said:
Lean your fuel mixture a bit if you can. High HC and CO can come from too much fuel. You may want or have to back off the timing a bit as well.
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Too lean will bring NOx, If they don't measure for that then its OK.

Do they hold you to an max idle? Sometimes kicking it up to 1000-1100 RPMS will help throughput.

Be sure you drive it 10 miles or so to get the Cats hot. They do take time to get to operating temp.
 
67Dart273 said:
Where is the timing set and what did you do to adjust the carb?

Generally make certain "everything" is in good shape, good plug wires and cap, plugs, do a compression / leak down and make sure the engine in good shape. Any evidence of leaking valve seals? Oil "puff" on startup?

Make sure float level on carb is not "high" and is dripping / dribbling/ "pullover" gas into throats. You can see by LOOKING at idle, down into the throats

Go look up some of the 74 specs. Set timing as retarded as it will run, TDC and make sure YOU DO NOT have a performance curve in the dist. Maybe just go buy a stock junkyard dist and get it "up to spec"
NO vacuum advance at idle, again, you want RETARDED and SSSSSLLLLLLLllllllooooowwww advance curve

Make sure it has a "hot" Tstat. Factory are 190-195-ish don't run a 180 and GET IT CLEAR UP TO TEMP before testing

Carb. Set idle "a bit" high and peak the idle mixture screws with a vacuum gauge, then "bump" them to the lean side (CW) just a tiny bit
Click to expand...
Everything is new. I have less than 6,000mi on stock rebuilt 318. The carb is stock jetting except for heavy step up springs. (Maybe lighter springs now I think of it to hold the metering rods down longer) The distributor is a new stock replacement. FSM calls for 08*BTDC, so I can stand to retard my timing and pull that vacuum line before retesting. I have a 180* tstat in place. I did keep shutting the engine off while waiting in line, so next time I'll keep it running. I have gas in the tank from May, soo... could it be an issue? I'll add fresh gas too.
Thanks! More for me to look at.
 
Put some methyl hydrate in your gas before you go test it works well
 
gliderider06 said:
Timing is at 18* initial
Click to expand...
That's pretty high for stock cam.
It may seem like the engine likes it in neutral, but in gear its probably too much advance.

Also going with more advance is longer burn time which favors leaner mixtures. But leaner may not burn as completely. its all balance.

I'd try for less timing. Maybe 12* at 700 rpm, then adjust mixture
 
Drop the timing down to 5*.
 
Cats dont like HC. They also work better with heat. Get them working and they will help clean up the other stuff - if they are three way thats even better. So again less timing at idle will help by increasing the heat in the cylinder walls and exhaust.

Here's a combustion byproducts chart that shows the relationship of AFR to left over HC and CO, etc when there are no cats.
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Early smog era engines without cats were set up to idle around 14 to 14.2:1 AFR.
By '87 with cats they may have wanted it a little leaner, but off the top of my head I don't know for sure.
 
gliderider06 said:
The carb is stock jetting except for heavy step up springs. (Maybe lighter springs now I think of it to hold the metering rods down longer)
Click to expand...
If the carb is setup properly, the step up is irrelavent to the idle mix.

gliderider06 said:
The distributor is a new stock replacement.
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Mmmmm...from a part store? If so then its generic and may but more likely may not actually have the same advance as the original.
gliderider06 said:
FSM calls for 08*BTDC, so I can stand to retard my timing and pull that vacuum line before retesting.
Click to expand...
OK. But my advice is to get there in a couple of steps. Each time reduce the initial 5 or 6 degrees, readjust the engine speed, adjust the idle mixture, then repeat. Too big of a jump and it may be difficult to keep it running.

Test your results by how the engine responds when you put it in gear or slip the clutch into first. If it dies then you'll have trouble at inspection!
 
Here is my story....1994 Dodge Ran 2500 5.9 with 330,000 on it.....every year I smog it I added a 50/50 mixture of e85 and regular gas....making sure the tank is near empty....every year it passes.....last year....i did not add the e85 to the tank and it failed the smog test.......I told the smog tech i would be back in a hour for a retest...drove down the gas station...added 5 gallons of e85 to the existing gas in the tank....drove around for 15 minutes to ensure the new mixture of fuel was getting to the engine....back to the smog station...hooked it up ....passed with no problem.....smog tech asked me what i did....told him.....went and added more gas to tank to dilute the mixture....

the sniffer will not see the e85 that is being burned...

been doing that for a number of years...
 
Mattax said:
That's pretty high for stock cam.
It may seem like the engine likes it in neutral, but in gear its probably too much advance.

Also going with more advance is longer burn time which favors leaner mixtures. But leaner may not burn as completely. its all balance.

I'd try for less timing. Maybe 12* at 700 rpm, then adjust mixture
Click to expand...
Makes sense. It has #302 heads on it so I suppose that is probably not liking the initial timing either. I have tuned it this way to get me the best MPG on the highway. What everyone is saying makes sense to me.
Thanks
 
70aarcuda said:
Here is my story....1994 Dodge Ran 2500 5.9 with 330,000 on it.....every year I smog it I added a 50/50 mixture of e85 and regular gas....making sure the tank is near empty....every year it passes.....last year....i did not add the e85 to the tank and it failed the smog test.......I told the smog tech i would be back in a hour for a retest...drove down the gas station...added 5 gallons of e85 to the existing gas in the tank....drove around for 15 minutes to ensure the new mixture of fuel was getting to the engine....back to the smog station...hooked it up ....passed with no problem.....smog tech asked me what i did....told him.....went and added more gas to tank to dilute the mixture....

the sniffer will not see the e85 that is being burned...

been doing that for a number of years...
Click to expand...
I need to find a station around here that sells e85 and dump some in. I heard gas line antifreeze has the same effect, but you need A lot of it.
I might try this with everything else
 
I still remember "the old days" when this stuff got ramped up. Before I got out of the Navy, NAS Miramar, San Diego, 1974, CA was requiring retrofits clear back to 55. you had to buy a retrofit kit, likely "the best" was made by Carter. This was a control box, tied in to a temp sensor with a solenoid valve which killed ALL vacuum advance until the engine got "too hot" (It turned on the advance to cool down the engine, not for performance)

In addition, the instructions told you to retard the SH*T out of the timing, lean down the carb (set on an analyzer) and then it had some add on idle screw caps with bright green RTV to show that is what you did.

A more simple kit DID NOT have vacuum advance. That kit permanently capped the advance hose with bright green plugs and caps, and same green caps on the carb. They burned down a LOT of engines
 
1987? I though they were going easy on the older stuff....I have an 86 Mustang in Pa and all it gets is gas cap test and visual that all the smog equipment is still there...
 
67Dart273 said:
I still remember "the old days" when this stuff got ramped up. Before I got out of the Navy, NAS Miramar, San Diego, 1974, CA was requiring retrofits clear back to 55. you had to buy a retrofit kit, likely "the best" was made by Carter. This was a control box, tied in to a temp sensor with a solenoid valve which killed ALL vacuum advance until the engine got "too hot" (It turned on the advance to cool down the engine, not for performance)

In addition, the instructions told you to retard the SH*T out of the timing, lean down the carb (set on an analyzer) and then it had some add on idle screw caps with bright green RTV to show that is what you did.

A more simple kit DID NOT have vacuum advance. That kit permanently capped the advance hose with bright green plugs and caps, and same green caps on the carb. They burned down a LOT of engines
Click to expand...
man, I bet the workaround on that was to get it inspected then swap the engine on Saturday, swap it back in a year...
 
Dartswinger70 said:
man, I bet the workaround on that was to get it inspected then swap the engine on Saturday, swap it back in a year...
Click to expand...
I only knew about this because of my part-time job at NAS Miramar auto hobby shop. Part of my job was to set up tuneups for guys on the tune-up machine. I/ we were not smog licensed. Several guys had come in with cars they had bought locally that had been "upgraded." I about sh*t when someone rolled in (this was early 70's) with a 55 chev with this junk installed. Many guys were not "smog savvy." So yeh, we "lost" a few of these
 
We still have to smog test vehicles '76 and newer here in Ca. I remember back when I had my repair shop that some smog equipment actually made more smog than if it was missing. A case in point was a late '60's Mustang with a 289 that came in the shop for a tuneup. The car ran perfect after the tuneup, and the emission specs were way below max allowed. The customer had to take it to a test only station to get a smog certificate. It failed the visual.....missing smog equipment. That particular year came in both a Ca. smog and non-Ca smog version, and the customer's car was the Ca version. No price limit on missing smog equipment, so, after spending hundreds of dollars rounding up all the smog gear (mainly the air pump, brackets, injection tubes, heat stove stuff, etc.) the cost of getting it installed and working, the smog specs went way up. We could barely get everything in specs at the same time and settings.....and it didn't run near as good either. It was totally ridiculous to make a great running engine that hardly polluted into one that didn't run near as good and polluted more, not to mention the extra cost to make it that way.
 
Dartswinger70 said:
1987? I though they were going easy on the older stuff....I have an 86 Mustang in Pa and all it gets is gas cap test and visual that all the smog equipment is still there...
Click to expand...
I wish! Shoot, they failed me last inspection B/C I didnt have cats on it, even though I passed the sniffer test. I was pissed. An extra $160.00 for nothing.
 
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