390 running rich need it to pass emissions

[RayLCC]

The 390 in this truck is supposed to be out of a Mercury Monterey. ( 65 I think he said. The engine is orange with the Mercury lightning valve covers.) It has a two barrel carb and is running very rich. The carb could probably use a rebuild but I'm on a temp tag and wont have the time or money to rebuild it before the tag expires and it has to get emissions tested to get plates. I'm going to get collector plates, so if I can get it to pass, I will have another five years before another e-test to get it running right. Is there any tricks I could do to get it to pass?
Thanks for the help.

[68swb]

i am a state inspector in tx. and "just playing around w/ the machine" if you take off the air breather it will lean it up. but i dont do that on any "e-test" b/c that is not legal. but a clean air filter [ or none ] will help.

[68F250]

How do you know it's running rich, can you smell it?

If the CO numbers are too high, try leaning out the idle mixture screws. Start with them a couple turns out (CCW) or to where you get the fastest idle speed and then turn them both in (CW) equally a little at a time until the rpm drops around 100 rpm but is still smooth.

If the HC is too high, you've got other problems like too much blowby.

[jor]

I'm trying to pass emissions as well (Arizona). Here's what I do:

* Timing at 5° BTDC (normally it's 8+)
* Very lean fuel
* New PCV valve
* Add one gallon of denatured alcohol to 1/2 tank fuel ($9 per gal)
* Set the idle a couple of hundred above normal (maybe 875 or so)

Good luck.
jor

[RayLCC]

Thanks for the tips, everyone. By denatured do you mean rubbing alcohol or something else? Where would I get that?

[jor]

"Denatured alcohol is ethyl alcohol (ethanol) to which a small percentage of methyl alcohol (methanol) has been added to render the mixture poisonous."

You can get "denatured alcolhol" at a hardware store. I'm going to do the emissions test Saturday so I just picked up a gallon. It is $10 per gallon. The guy at the hardware store (Ace) told me a lot of guys are buying MKE instead. It stands for methyl ketone or something. Anyhow, it is sold in 32 oz containers and he told me you add three ounces per gallon of gas so one can of this stuff to a half tank would be similar to a gallon of the denatured alcohol. I didn't notice the price.

Good luck.
jor

[jor]

I passed!!! (failed last week) I had lots of room to spare with 110 hydrocarbons and 3.31 carbon monoxide (450 and 5.00 standard, respectively). Anyhow, I'm good for another year. Feels great!

I used my standard setup:
* High idle (850-900)
* Lean mixture
* 1 gallon denatured alcohol
* Retarded timing (5° BTDC)

Great day! Good luck to all in the same boat.
jor

[NM5K]

I passed!!! (failed last week) I had lots of room to spare with 110 hydrocarbons and 3.31 carbon monoxide (450 and 5.00 standard, respectively). Anyhow, I'm good for another year. Feels great!


Congrats...I know the feeling...But with other
vehicles...I'm sooooooo glad I don't have to mess
with any emissions tests, being my trucks are
both over 25 years old. Thats a major incentive
to driving an older vehicle in this state. I went
through emissions hell with an old V6 monte
carlo I had. And the real problem was ignorant
emissions system mechanics. The problem lasted
about 3 years, with me spending about $6-700
bucks on emissions "repairs"... Sad part was...
They didn't really repair doodley...Just rebuilt or
changed perfectly good parts. *I* was the one to
finally find the *real* problem with the system.
The "air" hoses were connected backwards.
Being it had a new cat, after fixing that, it blew
about a "60" on HC test.
In that 3 years, I studied up on most of the emissions
systems, and can work on them no problem now.
I'm probably better than some of the clowns I see
doing it for a living. I'm serious...Some should go
back to working at taco bell, or wherever they
came from. Emissions testing is one heck of a
money making racket. They worry about cars
and lawnmowers, but let the refineries on the
east end of Houston belch puke 24/7. :/
MK