Failed CA Smog BAD

[scarydriver]

Hey All,

So my truck just failed a smog check miserably. My HC numbers are off the charts:

Idle: Max 250 - Measured 323
2500 RPM: Max 200 - Measured 1020

I added a gallon of denatured alcohol to the 1/8 full tank before heading over there. I figured that would help me pass with flying colors... obviously not.

My 60 passed no problem a year ago when I bought it. The only thing that has changed since then is that I can't fully tension the belt on the smog pump because the bolt is stripping out the threads in the pump. Because of that, when it revs above 2000 RPM, the belt loses tension, and squeals like crazy.

1. If the belt is losing tension like that, could the pump not be turning enough to do its job?

2. If the pump is not doing its job at 2500 RPM for the test, could that cause my HC numbers to be as high as they are?

3. If not, where would be the best place to start looking? I think I have the emissions manual around somewhere, but it would be nice to narrow this problem down further before I start tearing into everything...

4. Or is the whole denatured alcohol thing just a practical joke that screwed me over?

Thanks for your help guys!
Neil

 

[D'Animal]

I believe the pump is only really doing something when you accelerate or decelerate. I am not a smog guy though.

 

[acarnes83]

I'm fairly certain your smog pump has nothing to do with it because my Chevy 350 doesn't have any emissions equipment save PCV and my HC number at 2500 RPM is only 169. 2 more cylinders, no emissions equipment (including no cats), and roughly 700 lower on HC.

I'm wondering if it might be the high concentration of alcohol in the fuel. Alcohol combusts at lower temperatures than gasoline due to the oxygen molecule that the compound contains. My thought is that the alcohol is combusting first and driving the cylinders while leaving a lot of your gasoline unburned (which would account for the extreme HC levels).

I would say drain your tank, fill it with premium, drive it for a while, and go test again.

 

[John Smith]

The denatured alcohol trick works. What is your timing set to?

 

[ToyotaDon]

Smog tech here, but not much experience with the 2F.

Smog pump helps the catalytic converter work more efficiently, and that system needs to be operating properly.

Alcohol may make the engine run leaner, which can contribute to higher HydroCarbons.

 

[scarydriver]

The denatured alcohol trick works. What is your timing set to?

7 BTDC

Smog tech here, but not much experience with the 2F.

Smog pump helps the catalytic converter work more efficiently, and that system needs to be operating properly.

Alcohol may make the engine run leaner, which can contribute to higher HydroCarbons.

So from what I've been reading online, it sounds like the denatured alcohol trick works great at lowering CO levels... but from what you're saying, it might not be the best for the HC levels...

Maybe I should just take it back after running a new tank of gas through it?

 

[Bosscamocruzr]

scary driver you are correct it helps lower co by running LEANER and this will INCREASE NOX. so this is not your issue.
i am a smog tech as well. my 60 did this same thing. make sure your carb is tuned properly i rebuilt mine. i ran mine through and still barly failed. i found my cat had failed from running rich to long (2years). these are what i would look at also make sure you have good compression.
what you must find is what is causing you to have unburnt fuel(HC). plugs timing fuel any of these could be the problem
toyotadon--- leaner increases cylinder temps witch increases nox formed at 2500 degrees.

 

[Cruiserdrew]

Does everything work in your truck? Are all the vacuum hoses routed correctly? Has your carb ever been rebuilt? My guess is no to all. This is usually the case in 60s.

I basically had to start over. New EGR, new vac hoses, carb rebuild and new cat. That was 3 smog tests ago and it just passed again this month with very low emissions. Even the tech commented that it ran clean for an old truck.

Unfortunately, everything kind of slowly degrades over time leading to a failure like this. You are running very rich, so start with a carb rebuild and work from there. My guess is you need a carb rebuild and a new catalytic converter. Also you mention your smog pump cant be tensioned right, so fix that as well. There are no short cut mechanic in a can type fixes.

 

[scarydriver]

Does everything work in your truck? Are all the vacuum hoses routed correctly? Has your carb ever been rebuilt? My guess is no to all. This is usually the case in 60s.

As far as I know, yes, and no.

When I first bought the 60 last summer, I had to go over the entire system to get it to pass smog. I traced every vacuum line and fixed the ones that were hooked up incorrectly. I also replaced the EGR modulator as that was screwing up the EGR system. After a bunch of work, I took it back and it passed with flying colors. The HC and NO numbers weren't even close to the max allowed.

Now, just a year later, my HC numbers are crazy high. Everything else is fine. The CO % is super low. It passed all of the functional checks so I'm assuming all the systems are working...

Maybe a carb rebuild is in order - I'm sure it could use it.

 

[Gurr]

Luckily the cops around here are pretty mellow about smog, as long as dmv fees are paid and you have insurance they usually let you off the hook. I drove around for 5 months with expired tags when I was trying to pass smog. Send me a message if you need some help.

 

[SYCruiser]

Have you run through the emissions test procedure? I found that I had no air going to the cat due to a faulty vacuum valve. Fixed that, and bang, SMOG passes again with flying colors. I am not a guru by any means, but I can tell you more of what I went through if you like.

 

[OyajiJon]

Neil, I sent you a PM earlier, but I think I've found a smog pump you can have. I don't know if it will help, but at least it will be right. Call that number I sent you, and we'll arrange a time to get the pump to you.

-Jon

 

[Gurr]

What's stripping exactly, I do know that the air system should be perfect when you bring it in to smog. I would probably try to pass it on regular gas before jumping to any conclusions though.

 

[michael.e]

Mine was running rich and would not pass. I had Chris at Aptos garage work on it for a while and he recommended I take it to a place in Watsonville. Turns out one of my valves is sticking and I have yet to fix it..

PM me if you want any additional info.

 

[ToyotaDon]

scary driver you are correct it helps lower co by running LEANER and this will INCREASE NOX. so this is not your issue.
i am a smog tech as well. my 60 did this same thing. make sure your carb is tuned properly i rebuilt mine. i ran mine through and still barly failed. i found my cat had failed from running rich to long (2years). these are what i would look at also make sure you have good compression.
what you must find is what is causing you to have unburnt fuel(HC). plugs timing fuel any of these could be the problem
toyotadon--- leaner increases cylinder temps witch increases nox formed at 2500 degrees.

The problem is, he is running a two-speed idle test, not the loaded-mode test on the dyno, so there's no NOX reading to be affected by the mixture.

Back in the days before NOX began to be measured, we only had to look at CO and HC. For those gasses and that test, leaner mixtures (or ignition issues) will cause more HC.

 

[2mbb]

What is your residual oxygen (O2) reading? This might give you some indication whether there is not enough air. If you have residual oxygen, then the problem might be your cat. If you are consuming all your oxygen, you may need more air, or you have too much HC entering the cat.

Go through all the checks in the emissions systems manual to make sure all systems are operating properly. Then consider a carb rebuild. Go from there...

 

[scarydriver]

Neil, I sent you a PM earlier, but I think I've found a smog pump you can have. I don't know if it will help, but at least it will be right. Call that number I sent you, and we'll arrange a time to get the pump to you.

-Jon

Hey Jon - I missed your PM, so I sent one to you with my number.

What's stripping exactly, I do know that the air system should be perfect when you bring it in to smog. I would probably try to pass it on regular gas before jumping to any conclusions though.

The bolt that threads into the tab at the top of the smog pump to tighten it down is stripping out the threads in that tab. (Not the pivot bolt, but the one that tightens it to the curved arm that tightens the belt) Thanks for the offer for help, I'll let you know!

Mine was running rich and would not pass. I had Chris at Aptos garage work on it for a while and he recommended I take it to a place in Watsonville. Turns out one of my valves is sticking and I have yet to fix it..

PM me if you want any additional info.

I sure hope it's nothing like that, but I appreciate the info!

What is your residual oxygen (O2) reading? This might give you some indication whether there is not enough air. If you have residual oxygen, then the problem might be your cat. If you are consuming all your oxygen, you may need more air, or you have too much HC entering the cat.

Go through all the checks in the emissions systems manual to make sure all systems are operating properly. Then consider a carb rebuild. Go from there...

O2: Idle - 7.6% and 2500 - 4.5%

I have no idea if those numbers are high or low, so if you have any insight, I'd love to hear it.

I'll definitely be going through the checks in the emissions manual.

Thanks for the help, everyone!
Neil

 

[2mbb]

Here are my previous results over the years, both the idle test and the dyno test. I have had passing smog tests with oxygen as high as yours so it's not abnormal. In 2002 I failed smog. I did a lot of stuff, the last thing I did before finally passing was change both the smog pump and the cat.

 

[OyajiJon]

Hey Jon - I missed your PM, so I sent one to you with my number.

Well, Neil, that would be because I'm an idiot and sent the PM to someone else from Santa Cruz who is named Neil and drives a 60 series Cruiser (MountainCruiser62). How many of you are there? ;p

Anyway, I'll give you a call. Other Neil, if you read this, you're probably wondering what the hell I'm smoking while offering you free parts. Sorry...

 

[scarydriver]

Here are my previous results over the years, both the idle test and the dyno test. I have had passing smog tests with oxygen as high as yours so it's not abnormal. In 2002 I failed smog. I did a lot of stuff, the last thing I did before finally passing was change both the smog pump and the cat.

That's a hell of a spreadsheet you've got there - nice work on keeping track of that stuff! I really hope I don't need a new cat ($$$), but it sounds like I'll have a new smog pump soon enough... I'm sure I'll be able to track the problem down soon.

Well, Neil, that would be because I'm an idiot and sent the PM to someone else from Santa Cruz who is named Neil and drives a 60 series Cruiser (MountainCruiser62). How many of you are there? ;p

Anyway, I'll give you a call. Other Neil, if you read this, you're probably wondering what the hell I'm smoking while offering you free parts. Sorry...

That's too funny... I've only seen a handful of other cruisers around here, and to have another owner named Neil as well... damn.