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| Emissions Blues [message #130868] |
Sun, 19 June 2011 12:22  |
Chr$
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
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Senior Member |
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Failed Emissions this year. First pass failed both idle and cruise. I adjusted the idle level and mix a bit, passed that, but still fail cruise. The lockout tag on my secondaries is broken, so the upper secondary valve is probably opening, thus allowing some fuel to be drawn via the secondaries, richening out the mix. I am assuming this without actually being able to watch the carb on the Dyno at the Emissions testing station, as It appears that when I manually rev the throttle while looking at the carb, there is some fuel visible in the secondaries.
Any suggestions out there? I have to spend a considerable amount of $$ before they will waive me, and sending the carb out to be rebuilt by a pro has no guarantees, so I am leaning on TBI since I have to spend the money.
Anyone here have TBI and have an IM-240 Emissions Inspection every year?
If it is truly just the secondary lockout issue, anyone got a spare tag?
-Chr$: Perpetual SmartAss
Scottsdale, AZ
77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
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| Re: Emissions Blues [message #130880 is a reply to message #130868] |
Sun, 19 June 2011 12:56  |
roy1
Messages: 2126
Registered: July 2004
Location: Minden nevada
Karma: 6
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Senior Member |
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I don't know about Arizona but you should check and make sure they would let you change from a carburetor to F.I. with out some kind of special certification. Dump politics you know.
Roy
Roy Keen
Minden,NV
76 X Glenbrook
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| Re: Emissions Blues [message #130884 is a reply to message #130868] |
Sun, 19 June 2011 13:18 |
idrob
Messages: 645
Registered: January 2005
Location: Central Idaho
Karma: 0
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Senior Member |
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| Chr$ wrote on Sun, 19 June 2011 10:22 |
Failed Emissions this year. First pass failed both idle and cruise. I adjusted the idle level and mix a bit, passed that, but still fail cruise. The lockout tag on my secondaries is broken, so the upper secondary valve is probably opening, thus allowing some fuel to be drawn via the secondaries, richening out the mix. I am assuming this without actually being able to watch the carb on the Dyno at the Emissions testing station, as It appears that when I manually rev the throttle while looking at the carb, there is some fuel visible in the secondaries.
Any suggestions out there? I have to spend a considerable amount of $$ before they will waive me, and sending the carb out to be rebuilt by a pro has no guarantees, so I am leaning on TBI since I have to spend the money.
Anyone here have TBI and have an IM-240 Emissions Inspection every year?
If it is truly just the secondary lockout issue, anyone got a spare tag?
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Chris: a rebuilt carb from Dick P might be the least expensive solution, and a great carb to boot.
Rob Allen
former owner of '76 x-PB
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| Re: [GMCnet] Emissions Blues [message #130885 is a reply to message #130868] |
Sun, 19 June 2011 13:30 |
dan6
Messages: 10
Registered: June 2011
Karma: 0
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Junior Member |
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Chris,
have you considered registering it in a non-smog test county?
---- Chris Choffat <cchoffataz@yahoo.com> wrote:
>
>
> Failed Emissions this year. First pass failed both idle and cruise. I adjusted the idle level and mix a bit, passed that, but still fail cruise. The lockout tag on my secondaries is broken, so the upper secondary valve is probably opening, thus allowing some fuel to be drawn via the secondaries, richening out the mix. I am assuming this without actually being able to watch the carb on the Dyno at the Emissions testing station, as It appears that when I manually rev the throttle while looking at the carb, there is some fuel visible in the secondaries.
>
> Any suggestions out there? I have to spend a considerable amount of $$ before they will waive me, and sending the carb out to be rebuilt by a pro has no guarantees, so I am leaning on TBI since I have to spend the money.
>
> Anyone here have TBI and have an IM-240 Emissions Inspection every year?
>
> If it is truly just the secondary lockout issue, anyone got a spare tag?
> --
> -Chr$: Perpetual SmartAss
> 77 Ex-Kingsley 455, Power Drive, 3:21 FD, Quadra bag. The Engineer's Motorhome
> Scottsdale, AZ
>
> Photosite: Chrisc "It has Begun"
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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| Re: Emissions Blues [message #130911 is a reply to message #130868] |
Sun, 19 June 2011 16:26 |
Chr$
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
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Senior Member |
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Jim, your Fuelie is Port Fuel inj, isn't it? I was thinking of calling you... or your son.
Roy, They never do look under the hood, there are no catalytic converters, so they don't have to.
Dan, Regarding registering it in another county, yes, that is the backup plan, but I'd really rather it ran properly.
Rob, the only hangup I have on a rebuilt carb is will it pass or not? if not, I'm back to square 1 and have spent $300.
As it is, I already remove the air cleaner element and increase the idle a bit just before I get there. That helps a lot.
-Chr$: Perpetual SmartAss
Scottsdale, AZ
77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
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| Re: Emissions Blues [message #130941 is a reply to message #130911] |
Sun, 19 June 2011 19:17 |
roy1
Messages: 2126
Registered: July 2004
Location: Minden nevada
Karma: 6
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Senior Member |
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If you think it is the secondaries that is causing you to fail just temporally wire the secondary dump plate shut with bailing wire . It would have the same effect as replacing the missing tang. When I lived in So. cal they crawled all over the engine inspection time.
Roy
Roy Keen
Minden,NV
76 X Glenbrook
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| Re: Emissions Blues [message #130945 is a reply to message #130868] |
Sun, 19 June 2011 19:38 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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The lock out tang is not the problem. Once warm.... the only way to perform the test.... the choke is open and the tang moved out of the way making the secondary air valve able to open should it be called upon to do so by the throttle position of the secondaries. During the test you should only be on the primaries anyway unless they are laying into it. The thing to check is the vacuum pulloff and the 1" of hose the feeds it. The diaphragm goes bad in them and the vac hose can crack and look good but be bad on the back side. Truly a $.01 repair if that is it. Be sure the choke is wide open when warm and fast idle cam fully droping down. The heat tube could be rotted out to warm the choke. If no one has change the jets/ rods in the primary and the power valve is not stuck in the up position and the float is correct then the primary mixture should be OK. Set the idle mixtures to the lean side of best max RPM, and then lean each screw for a 25 RPM drop per side. If the timing is set right and advance working correctly it should pass.
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: [GMCnet] Emissions Blues [message #130966 is a reply to message #130911] |
Sun, 19 June 2011 21:15 |
dan6
Messages: 10
Registered: June 2011
Karma: 0
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Junior Member |
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Chris,
I had a 72 jeep cj when I moved here in '99 that could not pass. The emission station gave me a list of qualified repair shops that could do the same required tests to see if their repair worked. I had a shop in Mesa rebuild my carb, test it and it passed when I ran it through again.
IO don't know if that help is still available from emmissions now but certainly something to look into,
Dan
---- Chris Choffat <cchoffataz@yahoo.com> wrote:
>
>
> Jim, your Fuelie is Port Fuel inj, isn't it? I was thinking of calling you... or your son.
>
> Roy, They never do look under the hood, there are no catalytic converters, so they don't have to.
>
> Dan, Regarding registering it in another county, yes, that is the backup plan, but I'd really rather it ran properly.
>
> Rob, the only hangup I have on a rebuilt carb is will it pass or not? if not, I'm back to square 1 and have spent $300.
>
> As it is, I already remove the air cleaner element and increase the idle a bit just before I get there. That helps a lot.
> --
> -Chr$: Perpetual SmartAss
> 77 Ex-Kingsley 455, Power Drive, 3:21 FD, Quadra bag. The Engineer's Motorhome
> Scottsdale, AZ
>
> Photosite: Chrisc "It has Begun"
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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| Re: Emissions Blues [message #131028 is a reply to message #130868] |
Mon, 20 June 2011 05:50 |
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mike miller
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
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Senior Member |
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| Chr$ wrote on Sun, 19 June 2011 10:22 |
... The lockout tag on my secondaries is broken, so ...
... so I am leaning on TBI since I have to spend the money. ...
|
When I got my carb from Dick P, it did not have a secondary lock out tang. After talking with Dick, I had the impression that he removes them. He told me that if I was worried about it, I could remove the one from my core before returning it.
Based on Dick removing them, unless it is keeping something closed that should be opening, I do not think your tang is causing your problem.
Besides the other benefits, if installed with a computer controlled distributor, fuel injection can improve your mileage... slightly. (1... maybe 2 MPG.) If you are planning to keep your coach for a long time, or are going on a long trip or two, the system could pay for itself.... and help you pass emissions. (If they do not expect your engine to be stock.)
Note: At $4 gallon gas, the difference between 8 and 9 mpg is about $60 for every 1000 miles.
Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo'
http://m000035.blogspot.com
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