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High CO numbers failed smog test oregon

Posted: Thu Oct 12, 2017 4:29 pm
by 78 WIDETRAC
HC. 220 CO. 1 these are the numbers to be at or under.

My numbers we're HC 140 at idle 173 at 1/3rd throttle I don't know the exact rpm no tacometer. And the CO was at 5.0392 at idle and 4.9097. I'm truly tired of having this problem every time I go through smog in Portland

I have a brand new 2 bbl carb.

It runs smooth and has a solid 17" of vacuum. I'm pretty sure the timing is good but that's very hard to see. But I just timed it yesterday. And it seems to be good. Only odd thing is it has a slight bog.

1984 grand wagoneer. 360. T-18 manual trans. All smog gear intact except smog pump. It has the upgraded cat that does not have the air tube. Throw me an idea if you have any. Oh yeah fresh oil change. And I ran sea foam through the intake.

Re: High CO numbers failed smog test oregon

Posted: Thu Oct 12, 2017 4:44 pm
by babywag
carb too rich...
blown power valve be my first guess.

when asking about smog failures best post pic of test sheet w/ all numbers/info.

what do plugs look like?

Re: High CO numbers failed smog test oregon

Posted: Thu Oct 12, 2017 4:50 pm
by 78 WIDETRAC
I would love to post a pic but seriously struggle in that dept. I will pull plugs this weekend. They have been in for a while. Do you recommend a good plug? I run autolite 65's. Power valve? It is a brand new carb from guaranteed carbs. is there a vacuum test i could do to test it?

Re: High CO numbers failed smog test oregon

Posted: Thu Oct 12, 2017 7:20 pm
by babywag
I just use cheap copper plugs as well, have always worked fine for me.
What I meant is are they all black/sooty.

I can’t even count how many new bad power valves I’ve gotten or that failed shortly after a rebuild. They’re just junk & don’t last IMHO.
Repeated failures and having to frequently replace is a contributor to why I switched both of mine away from MC2150.
Pull vacuum line to power valve cover and see if smells of gas or has visible gas there.
Is choke opening fully?
If stock air cleaner? does it have an inner flap? if yes make sure it’s opening.

Re: High CO numbers failed smog test oregon

Posted: Fri Oct 13, 2017 7:00 am
by csuengr
The smog pump not hooked up isn't helping you. It might be hard to pass without it.

The power valve might be leaking, but if it were completely blown, your engine wouldn't run well.

The only way to get it to run leaner is to up the idle speed and use smaller jets.

Re: High CO numbers failed smog test oregon

Posted: Fri Oct 13, 2017 8:09 am
by letank
We need all the numbers associated with high CO, use one fo the free image hosting sites, except photobucket, or whatever it was called, I use google, I am sure others will chip in,

my favorite diagram

Image

Re: High CO numbers failed smog test oregon

Posted: Sat Oct 14, 2017 2:56 pm
by 78 WIDETRAC
Update
Thanks for the advise to all.
I was working out of town on friday.

Today I changed the plugs and ran it through the emissions station.

The Jeep dropped the readings in half almost.

Hydro carbons first test Idle 140 Second test (Today) 85 Max allowed 220 So thats great.

CO first test Idle 5.0392 Second test (Today) 2.5745 Max allowed 1

CO2 First test idle 11.3 Second test (Today) 13 Max allowed 6

I will try to post a pic of the plugs and test sheets.. I have to get one of the image hosting sites going.
Power valve seems good.

I feel like I may need to adjust the idle down I don't have a tac. It seems like its idling high. My guess is it is around 800-900 Rpm's

My Jeep has a manual trans and the carb was set for an auto trans so it should be lower since it doesn't drop some idle like a normal auto trans wagoneer.

Vac reading is 19 solid not moving at all, I run a vacuum gauge in my jeep. It runs great. no bog anymore. the station is closed until tuesday next week. I think the carb needs a qualified mechanic to adjust the air fuel ratios.

Re: High CO numbers failed smog test oregon

Posted: Fri Oct 20, 2017 8:37 am
by 78 WIDETRAC
Update:

I took it to a local garage. He said it all looks good just needs a carb adjustment.

$47.00 later and deq test and registration fees of $141.00. I'm good until 2019. If you are local I highly recommend this guy. Gary's Auto Repair on SE 91st and Stark.

Re: High CO numbers failed smog test oregon

Posted: Sat Oct 21, 2017 1:04 pm
by FSJ Guy
Awesome!! With a properly tuned carb and working emissions equipment, any FSJ will pass emissions.