Need your input on my smog test results (1 Viewer)

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So I decided to finally take my 76 40 for a smog test this afternoon. Didn't pass... I did the pre-test inspection only figuring I wouldn't pass. Here are my results. What do you guys think I should tweak?

SAM_0306.JPG
 
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Hahaha. I gassed up before arriving there and left it on pass floor board. He didn't see it there, so he punched in that it was missing... Geez!
 
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You are failing both HC and CO. YOur main problem is CO, which comes from running rich. Too much fuel or not enough air. Check fuel level in bowl and excess fuel dripping out of bowl vents. The HC may come from running rich too. It is too rich to make it seem likely to be an air injection system fault, but that is another possibility. Clogged air filter is another one. Power valve stuck open is another.
 
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before you get too involved - get a laser temperature sensor, and point it at your cat.... those readings suggest that it's simply not working (it will be in the 150-250 range if it's not working; 400 or hotter range if it is).
 
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Ok. I will try adjusting it in the morning. Do you think adjusting the fuel alone might resolve the issue?

It may be more than an adjustment problem. The air/fuel ratio is way too rich and there are a number of possible causes. I would start by checking the fuel level in the bowl and the operation of the power valve. If you pull a vacuum on it, you should hear a click as it moves up and down.
 
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Hahaha... Trust me... It's tempting.

On a positive note, I don't know how true this is, but the smog tech was telling me he recently went to a seminar where they discussed a new push for a state bill that would push the exemption year up to 1981.
 
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It may be more than an adjustment problem. The air/fuel ratio is way too rich and there are a number of possible causes. I would start by checking the fuel level in the bowl and the operation of the power valve. If you pull a vacuum on it, you should hear a click as it moves up and down.

The plug wires, air filter, spark plugs, dist cap are all new. I will admit, it does smell pretty rich when idling. I recently swapped the head gasket and had the head redone.
 
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Here is something else to consider, not sure if it would help much on your car.

- Before taking a smog test ensure that you have fresh gas in the car as it will burn cleaner.

- Take the car on the freeway and get it warm, well into operating temperature. This may be more for cars with cats than those without but not sure.

If the car is cold or not up to full operating temperature the choke make be partially operating and thus you would be running rich. Some shops don't bother to bring the car up to normal operating temperature and if you check your printout there is no mention of it anywhere. If you fail a test it usually means more business for the tester.
 

Spike Strip

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The push to move the non-test status up to 81 and older has been kicking around a while, now. It's pushed by the aftermarket and classic-car parts makers to obviously keep more older cars on the road. We'll see how effective is their lobbying... It would make a lot of Calif Cruiser owners do cartwheels in the street if it passed.

Has the carb been rebuilt? Sounds like it might be time...

Also, getting the A/F mix right and putting a $100 CAT on the truck (even though it's not required) will go a long way to helping you pass. AI looks good. Better O2 percent than my 60.
 
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Fingers are crossed... Hopefully it goes thru

The carb has not been rebuilt. I'm going to tweak it a bit and give it another test. I supposed throwing a 100 dollar cat in there for some added support would be good too. I've been driving it around with an undated one day permit from the DMV. But, I don't know how much longer my buddies with the CHP will let that one fly... Lol.

My friend Mark might be getting a visit from me pretty soon to rebuild the carb...
 
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When you go back for your smog check you may consider going to Cory at:

Smog Service Station
23221 Peralta Dr Laguna Hills, CA 92653
+19494583721

He came recommended by a Toyota Master Mechanic who owns a 40 and has smogged my 40's for years along with several other club members 40's... He will try as best he can to pass them... Good luck, you will need it!
 
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Power valve stuck open is another.

When is the power valve supposed to be open? Open is with manifold vacuum is applied?

I thought I had a '76 emissions manual, but it turns out it is a CA supplement. I found that Man-a-Fre had one in their closeouts section, so it's on the way.

If anyone wants to know how to service their Thermal Reactor, I've got the manual for that. :)

the smog tech was telling me he recently went to a seminar where they discussed a new push for a state bill that would push the exemption year up to 1981.

He may be referring to SB 1224. It was pushed by SEMA and others. It failed by a 4-3 in 2012. Google shows no evidence of this coming back at this time.

putting a $100 CAT on the truck (even though it's not required) will go a long way to helping you pass.

I'm not sure that's legal. :confused:

I've been driving it around with an undated one day permit from the DMV.

LOL. I keep a matching, working pen at hand at all times. :) I've also got a folded-up bike rack that happens to cover my sins just a bit.
 
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Joined
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Orange County, CA
When you go back for your smog check you may consider going to Cory at:

Smog Service Station
23221 Peralta Dr Laguna Hills, CA 92653
+19494583721

He came recommended by a Toyota Master Mechanic who owns a 40 and has smogged my 40's for years along with several other club members 40's... He will try as best he can to pass them... Good luck, you will need it!

Thanks for the recommendation. I'll definitely need the luck.
 
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The plug wires, air filter, spark plugs, dist cap are all new. I will admit, it does smell pretty rich when idling. I recently swapped the head gasket and had the head redone.

You can't smell CO because it has no odor, so there is no easy way of telling if it is running rich. You can smell unburned hydrocarbons, but that isn't necessarily from running rich.

When is the power valve supposed to be open? Open is with manifold vacuum is applied?

On a stock '76, it is controlled electronically by the ECC. Weak manifold vaccum holds it closed and when you put the pedal to the metal, the VSV vents it to the atmosphere through a small vacuum buffer tank to slow the opening. On the strictly vacuum controlled versions, they open when manifold vacuum drops to about 3 inches of water.
 

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