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Need help passing emissions!!!
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Author:  74A1Swinger [ Thu Sep 20, 2012 3:15 pm ]
Post subject:  Need help passing emissions!!!
I'm having a problem passing emissions after I've done a major tune up on the engine, carb, etc. and I'm confussed as to how this can be. Mainly, it was a little worse after I did the tune up this time and the last time I did a full scale tune up was 2 years ago and it passed each of those 2 years. :?

It failed on the CO's both idling and Loaded the secound time and only on the CO's at idle on the first time. here's the following results:

First test!
Loaded HC: 247 Limit: 400 Pass
Idle HC: 354 " " Pass
Loaded CO: 4.38 Limit: 3.75 Fail
Idle CO: 4.95 Limit: 5.00 Pass

Secound test!
Loaded HC: 231 Limit: 400 Pass (down)
Idle HC: 379 " " Pass (up)
Loaded CO: 5.55 Limit: 3.75 Fail (up)
Idle CO: 7.02 Limit: 5.00 Fail (up)

What I do know that is wrong with the car is that the carb was replaced with one from a manual trans and mine is an auto.; when rebuilding the carb I used the kit for my cars exact model (Holley 1945). And the engine has bad valve seals or guides (?) which showed up on a vacuum test. Also to add injury, the exhaust system is both needing replacement and is 1/2" dia. too small for the engine (225 sl6), so it's restricting the pcv air flow and at high speeds is reversing it based on the massive amount of black oily gue that gets shot onto the air filter at high speeds along with oil leaks that pop up out of nowhere, but go away at speeds under 50mph.

Anyway, at this point I don't have a emissions tester to check my work so I feel like I'm working in the dark. I thought maybe I should just lean out the idle mixture and increase the idle, but I'm not sure that would do the trick and I might have to pay for another test.

So I'm not sure what's the easiest way to get the car to pass.

Here's a list of items replaced:

PCV vacuum hose (OSAC to distributor)
PCV breather cap
PCV valve
fuel filter
dist. p/u assembly
plugs
plug wires
rotor
air filter
dist. cap
spark plug tube seals
ign. coil
gumout engine, carb., and fuel line cleaner (burned up a full tank of gas)
oil chg. and filter

I'll appreciate any help I can get.
Author:  Doc [ Thu Sep 20, 2012 3:58 pm ]
Post subject: 
How is the idle quality? Super-smooth or rough?

You may need to pop-off the valve cover and adjust the valve lash, going to the loose side of the spec. (.012 intake & .023 exhaust, or a few thousands looser if you can... with-out a lot of loud "ticking")

After that, get the engine completly hot and adjust the idle mixture screw in slowly, untill the engine starts to miss, then back-out just enough to get it to smooth-out... bisically, get the idle mixture as lean as you can, with-out mis-fire. or very little mis-fire)

Be sure the engine is hot when you do the next test.
DD
Author:  74A1Swinger [ Thu Sep 20, 2012 4:48 pm ]
Post subject: 
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How is the idle quality? Super-smooth or rough?
Pretty-smooth, could be just a tad smoother. But it idles better now than ever.

Quote:
You may need to pop-off the valve cover and adjust the valve lash, going to the loose side of the spec. (.012 intake & .023 exhaust, or a few thousands looser if you can... with-out a lot of loud "ticking")
I haven't done anything with the valves they sound great though. What will this do exactly?

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After that, get the engine completly hot and adjust the idle mixture screw in slowly, untill the engine starts to miss, then back-out just enough to get it to smooth-out... bisically, get the idle mixture as lean as you can, with-out mis-fire. or very little mis-fire)
I've basically done this already. I set the mixture using a vacuum gauge. I brought the mixture screw out to the highest steady vacuum reading (20 in Hg) and turned it in in 1/16 increments till it started to stumble and backed it out slowly till it stopped. Before that, I set the timing, with the vacuum advance hose removed from the dist. and plugged the hose, to the highest vacuum reading without any pinging from the valves. This turned out to be 10 degrees btdc (I'm not really sure the reading of tdc on the gauge is really tdc on the #1 cylinder though, because at 2 degrees atdc the engine runs really rough). And of course I made sure the engine was completely warmed up(ssssizzling).

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Be sure the engine is hot when you do the next test.
DD
Author:  Doc [ Thu Sep 20, 2012 5:17 pm ]
Post subject: 
Increasing the valve lash setting as much as you can will increase idle vacuum readings and help smooth the idle more.

Basically, you are "tricking" the cam timing & engine so it "sees" the intake valve close sooner, which increases DCR and cylinder pressure.

More lash also shortens the overlap event time, so less of the intake charge will get "sucked-thru" into the exhaust, during overlap.
And you delay the exhaust valve opening point, giving the mixture more burn time, before cylinder "blow-down" happens. (exhaust valve opening event)
All this tends to reduce emissions.
So... if you have not checked valve lash recently, it's time to do so.
DD
Author:  74A1Swinger [ Thu Sep 20, 2012 5:40 pm ]
Post subject: 
Doc that is really cool you are a Guru! Thanks I never knew that. I've never adjusted the valve lash before, I know that sounds really green, but in the past I had a friend who was good at that so I just let him handle that. I have rebuilt a 67 Chevy 283 in the past with the help of some friends and got 100,000 miles out of it (besides just the usual automotive stuff).

As I recall it gets a little messy with the 225 because it has to be done while the engine is running? I'll have to look that up and go over it pretty good. Any tips?

Also while we're talking any ideas on how to cheaply check the mixture readings before I go back in to test?

74
Author:  SlantSixDan [ Thu Sep 20, 2012 5:52 pm ]
Post subject:  Re: Need help passing emissions!!!
Your numbers (all of them, even the 'pass' numbers) are higher-to-way-higher than they should be. Something's wrong and needs fixed -- don't resort to "tricks" like de-lashing the valves, de-adjusting the idle, or pouring in "emission test in a bottle" types of gunks until after you've fixed the real problem and it still won't pass (which almost certainly won't happen).

Your carburetor is almost certainly running way too rich for one reason or another. You may be able to repair it with another try, or it may be "terminal" and due for replacement with a new one (not a "remanufactured" one; those are junk). Or it may be strangled by an oil-soaked air filter; see below.

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.
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What I do know that is wrong with the car is that the carb was replaced with one from a manual trans and mine is an auto
That will not cause your problems.
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And the engine has bad valve seals or guides (?) which showed up on a vacuum test.
What test, exactly, did you do? What did you see?
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the exhaust system is both needing replacement and is 1/2" dia. too small for the engine
What makes you say it's too small? What size is it?
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so it's restricting the pcv air flow
No, it's not. The exhaust system, no matter how clogged or too small, cannot restrict PCV airflow.
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and at high speeds is reversing it
Your engine may be whipped/worn out, but if you did a vacuum test sensitive enough to pick up worn valve guides and it didn't show exhaust restriction, your exhaust system is not contributing materially to blowby.
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based on the massive amount of black oily gue that gets shot onto the air filter
Sounds like your engine is whipped/worn out or else the PCV system is not working correctly. This will not stop with a new exhaust system.
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So I'm not sure what's the easiest way to get the car to pass.
Wrong question. Fix the car so that it is running correctly and in good mechanical condition, then it will pass the test. The object is not to sneak past the test, the object is to get the car running right. That's why the car is periodically tested, to see if it's running right. Yours is not.
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PCV vacuum hose (OSAC to distributor)
There is no such hose. The PCV system is entirely separate from the distributor vacuum advance system.
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PCV valve
How certain are you that it's the correct one?
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dist. p/u assembly
Why?
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plugs
What spark plugs did you install, gapped how, and did you remove the metal ring washers from them before installing them?
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air filter
which is now useless if it's been soaked down with oil coming into the air cleaner assembly via the breather hose...this alone could easily strangle the engine enough to produce the numbers you blew on the emission test.
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ign. coil
Why?

What is your ignition timing setting? Have you checked for timing chain slack? Sounds like the engine is well overdue for a valve adjustment, too. Tune-up parts and technique suggestions are in this thread.

The very first thing you should do is get all three books described in this thread, as quickly as you can. You are starting from a near-total lack of knowledge and understanding of how your car works (and doesn't work), so all you can do at this point is spend (lose) money.
Author:  74A1Swinger [ Thu Sep 20, 2012 7:26 pm ]
Post subject: 
Hi Dan,

Good to hear from you again! I'm going to take some time to check out all the info and answer all of these questions you've raised. I didn't know really that the valve adjustment was delashing the valves. I guess I don't really want to do that, because it sounds just as bad as leaning out the idle mixture which would have a long term negative effect on the engine, and I plan on keeping and restoring my car (probably restomod), I'm just strapped for cash right now so I'm just trying to get by untill later date. I really was looking more for something simple that I may have missed that would result in being able to just pass the test.

I do plan on getting the books and doing it right, but right now having the car pass is the most important thing as I currently have no support network and live in an area wear personal transportation is the only way of being able to get around. Also that's how I came to own this car because it was inexpensive, but at the same time caught my eye because it had a lot of potential and the work I have done has made the car look and perform a lot better than when I purchased it. It's a pretty good looking car and even the engine looks pretty good, it just needs the right work done, but I have to also keep it up and running till I can afford to do that.

The tune up work I just did was over due and needed to be done, I just thought it would make more of a difference than it did. And I sure didn't expect it to perform worse, so your right, something is very definately wrong it's just that I haven't been able to figure that out at this point yet.

One question that jumped out at me is the one about what I listed as the PCV vacuum hose, :roll: sorry I guess I was in a rush there, it's just the vacuum hose that goes from the OSAC valve (which delays the change in ported vacuum from idle to part throttle) to the distributor vacuum advance. It was old and a little tough in one area and it needed to be replaced and it did make a difference in the car's performance, because I did that one a few days before the rest was started and you could definately tell the difference.

So, with that I'm going to get back to you tomorrow with the proper answers to your questions. Today was hectic, taking care of a loved one with cancer and I need to catch some zzzzzzzzzzzz's.

Thanks,
74
Author:  kesteb [ Thu Sep 20, 2012 9:52 pm ]
Post subject: 
What god for saken state do you live in that requires a 37 year old car to pass emissions.

Also would it be cheaper to pay the fine, then fix the non-compliance.
Author:  SlantSixDan [ Thu Sep 20, 2012 11:32 pm ]
Post subject: 
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What god for saken state do you live in that requires a 37 year old car to pass emissions.
There are plenty of states that do, and if the car's being driven regularly, that's reasonable and proper.
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Also would it be cheaper to pay the fine, then fix the non-compliance.
Not with gasoline at $4+/gallon, it isn't. A car blowing those filthy numbers is pissing gasoline money right out the tailpipe.

But thanks, Kesteb, that was a fun throwback for the kind of stinkin' thinkin' that used to be common 40 years ago before we knew better. How 'bout if next we have "It's safer not to wear a seatbelt because then in a crash I'll be thrown clear of the car!" Or wait, no, how 'bout "I dug about an 8" diameter by 18" deep hole in my back yard and filled it with gravel; when I change my oil I pour the old oil on the gravel and it's absorbed in the ground by the time the next oil change comes around". C'mon, it'll be fun...what others can we think of? "More doctors smoke Camels than any other brand"?
Author:  ESP47 [ Fri Sep 21, 2012 6:52 am ]
Post subject: 
I see no problem at all with doing a valve adjustment and setting it at the looser side of the spec. The spec is there for a reason and your car will run fine as long as it's in spec. This adjustment is one of the most important "to-do's" to get a better running slant six.
Author:  wjajr [ Fri Sep 21, 2012 7:25 am ]
Post subject: 
I love this stuff, ok, I’ll bite.

I think you meant to reference Chesterfield brand; “not a cough in the pack, doctors recommend themâ€￾, and “Schaefer is the one beer to have when you’re having more than oneâ€￾. That should cover oral habit department via Madison Avenue’s long tradition of truth in advertising.

I like the backyard gravel oil reclamation recycle method previously outlined; replacing vital natural resources to the earth for later generations to discover is only fair…
Author:  74A1Swinger [ Fri Sep 21, 2012 2:07 pm ]
Post subject:  Re: Need help passing emissions!!!
Quote:
don't resort to "tricks" like de-lashing the valves, de-adjusting the idle, or pouring in "emission test in a bottle" types of gunks until after you've fixed the real problem and it still won't pass (which almost certainly won't happen).
I wasn't trying to do any kind of trick or emission test in a bottle, and I wasn't using gunk or crap or whatever you want to call it, I was merely using the gumout product for what it was intended to be used for which is to remove carbon, varnish, rust, and other contaminants from the fuel, carb, and engine combustion chamber. Do you have a problem with gumout carb cleaners and their other products? I've used them in the past with great success within the confines of their intended use.
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Your carburetor may be strangled by an oil-soaked air filter; see below.
I stated that I replaced the air filter as part of a comprehensive tune up!


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What I do know that is wrong with the car is that the carb was replaced with one from a manual trans and mine is an auto
That will not cause your problems.
Thankyou! I had thought that maybe the internal pasages in the carb might be differently sized compared to the carb that is in the car now and that by rebuilding it with the stock rebuild parts they might have thrown that off, but now I know from your responce that a problem like that is "not the cause (of) your problems".
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And the engine has bad valve seals or guides (?) which showed up on a vacuum test.
What test, exactly, did you do? What did you see?
While doing some vacuum testing of the emissions system 8 months ago I had the gauge teed into manifold vacuum and at idle at that time it was lower than it is now (about 17 in Hg) and fluctuated rapidly in a range of about 3 in Hg. And as I increased the engine speed the needle would steady or smooth out.
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the exhaust system is both needing replacement and is 1/2" dia. too small for the engine
What makes you say it's too small? What size is it?
It's 1 3/4" in dia. on the exhaust pipe (from manifold to muffler) and 1 7/8" dia. on the tail pipe. Allpar.com says it should be 2 1/4 on both and that the factory purposely sent them out the door at 2" dia. to save money on each exhaust system.
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so it's restricting the pcv air flow
No, it's not. The exhaust system, no matter how clogged or too small, cannot restrict PCV airflow.
Well then, what could cause that and the following?
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and at high speeds is reversing it
Your engine may be whipped/worn out, but if you did a vacuum test sensitive enough to pick up worn valve guides and it didn't show exhaust restriction, your exhaust system is not contributing materially to blowby.


I did do the exhaust restriction test that is listed in the mighty vac owners manual and it failed the test!
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based on the massive amount of black oily gue that gets shot onto the air filter
Sounds like your engine is whipped/worn out or else the PCV system is not working correctly. This will not stop with a new exhaust system.
So what else can cause this aside from bad breather cap, pcv valve, or hoses?
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So I'm not sure what's the easiest way to get the car to pass.
Wrong question. Fix the car so that it is running correctly and in good mechanical condition, then it will pass the test. The object is not to sneak past the test, the object is to get the car running right. That's why the car is periodically tested, to see if it's running right. Yours is not.
I really wish you wouldn't put words in my mouth and subjectively construe what I say in a negative fashion, it makes you look bad and you have a lot of good knowlege that you can help others with and that's why I came to this site I'm not looking for some back yard butcher boy approach, nor am I a back yard butcher boy, so don't imply it please!

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PCV valve
How certain are you that it's the correct one?
absolutely!
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dist. p/u assembly
Why?
Because the old one was the original and was rusty.
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plugs
What spark plugs did you install, gapped how, and did you remove the metal ring washers from them before installing them?
Champion copper plus, old ones were Champion platnum plus (oops!), spark plug gauge not feeler gauge (.035) specs said with or without rings, but after while working on coil I read the info you posted and saw it's best without rings.
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air filter
which is now useless if it's been soaked down with oil coming into the air cleaner assembly via the breather hose...this alone could easily strangle the engine enough to produce the numbers you blew on the emission test.
No!!!! it most certainly is not useless!!! Because I didn't run it above 50, which is the point where it starts to do that.
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ign. coil
Why?
Covered in my first thread/subject to this site, this is my second.
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What is your ignition timing setting? Have you checked for timing chain slack? Sounds like the engine is well overdue for a valve adjustment, too.
Timing setting is in the first post at the beginning, I suggest you reread that. I have not checked the timing chain nor have I adjusted the valve lash (refer to first post again)


Quote:
The very first thing you should do is get all three books described in this thread, as quickly as you can. You are starting from a near-total lack of knowledge and understanding of how your car works (and doesn't work), so all you can do at this point is spend (lose) money.
This is a very pompus statement! I know that I don't know it all, that's why I asked for help, but I expect that help to come with out an attitude. I know I probably won't be racing cars at the track, but you don't have to talk down to me either. I guess I just expected a more professional responce thats all.[/quote]
Author:  SlantSixDan [ Fri Sep 21, 2012 2:35 pm ]
Post subject:  Re: Need help passing emissions!!!
There is no fluid you can use that will remove rust. Pour-in additives like you used can clean up minor amounts of gum and varnish. If there's significant crud in the system, it has to be taken apart and cleaned manually. Your car has a problem that needs to be fixed, and my comment was advice not to use one of the "Pass emissions or your money back!" types of additives instead of fixing the problem.

There is also no such thing as "pinging from the valves".
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It's 1 3/4" in dia. on the exhaust pipe (from manifold to muffler) and 1 7/8" dia. on the tail pipe.
That is the factory-specified size.
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Allpar.com says it should be 2 1/4
Nope. A-bodies with slant-6 engines never left the factory with 2¼" exhaust systems front to back. The only \6 A-bodies to have a 2¼" headpipe (manifold to muffler) was the '76 Feather Duster/Dart Lite.
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the factory purposely sent them out the door at 2" dia. to save money on each exhaust system.
The factory used 1-7/8" pipe (not 2") to save money, yes. A larger headpipe (at least) will increase exhaust flow, yes. Your system is not, however, "too small". It's just not optimally large. A fine distinction, but a real one. Zillions of Darts and Valiants ran just fine (and many still do) with the factory exhaust system spec. Yours may be extra-restrictive due to a blockage in the muffler, that happens and should be fixed.

Other causes of improper PCV function, aside from incorrect PCV valve, include incorrect vacuum hose routing...incorrect carb base gasket blocking vacuum to the PCV hose.

PCV and exhaust system fixes will not compensate for a worn-out engine.

I reject your complaints about my manners. You're starting from very unclear understanding of how your car works. I'm trying to help, and I'm reacting to what you're typing (e.g., "what's the easiest way to pass the test"). If that's not what you meant, then you'll have better results typing what you mean. Pointing you at those books is not "pompous". You are not being mocked or derided, you're being pointed in a productive direction. There is no shame in ignorance; it's easily fixed. The shame is in willfully maintained ignorance. You get to choose whether you're going to educate yourself or not. If you refuse to help yourself by learning about your car, you cannot reasonably expect others to be very interested in helping you.
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I guess I just expected a more professional responce thats all.
Professional consultants charge money. Giving advice on this forum pays $0.00 per hour or per post. Those of us who try to help you do so voluntarily. That being the case, the attitude adjustment needed is on your end—a modicum of gratitude is more than warranted—but that's another decision for you to make. I'm sorry you find my assistance disagreeable; I certainly don't want to make you feel bad, so I'll move on to helping others. Best of success making your car run right.

User 74A1Swinger is <IGNORED>
Author:  sandy in BC [ Fri Sep 21, 2012 3:16 pm ]
Post subject: 
Jeeze Dan.....you are getting all pissy again.
Author:  Eric W [ Fri Sep 21, 2012 4:37 pm ]
Post subject: 
Lean out the carb. Run the tank almost empty. Put a small bottle of rubbing alcohol in the tank. Go pass the test. :mrgreen:
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