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MG MGB Technical - Passing Emissions Test

I just received my notification to take my 79 MGB in for emission testing (Illinois). It doesn't have a cat. converter. It does have a road cam with the Weber 2 barrel. Is there anything I can do to help make this car pass the test? Will advancing the timing or putting alcohol/methanol (gas dryer) in the gas help? Appreciate the help.
Mike D.

I also have to smog my new '79... the guy I am buying my air pump from has recommended that I run the tank down to about 60% and refill with methanol... then adjust the idle so the car won't stall. He says this will reduce your emissons, sometimes all the way to zero! I haven't done it myself, but I am planning to try it soon.
Jeremy

Just a word of caution, it seems that I recall hearing that methanol eats rubber and aluminium fairly quickly. I think having it in there for a day wouldn't hurt, especially if it's mixed with gas. If it were me, I'd plan on using it all up after the test. Anybody else know about this?

-Jared
Jared Snider

Mike,
I also have a '79 B. I was having trouble passing the e-test a couple of months ago. I recieved two recommendations in regards to fuel alcohol mixtures that would help with passing.

1) Run the tank to nearly empty then add a mixture of 50/50 gasoline/methanol.

2) Run the tank to nearly empty then mix a pint of "Heet" red bottle (isopropl alcohol) with one gallon of gasoline. Add this to the gas tank, then take it in for the test. After the test you can immediatly fill the tank and that will dilute the mixture.

I used the second recommendation with great results.

Also:
I found it very helpful to purchase a gunson's exhaust gas analyzer, to check the CO prior to going for the test. I've had to struggle with the test every year for the past several years. I usually do ALL the recommendations prior to going in. This year I installed a new Cat. converter (the old one was a shell) and rebuilt the carb. Always use new spark plugs, check and/or adjust the timing, valve lash clearences (towards the loose side), new points and condensor would not hurt, as well as a fresh oil change.
In the past I have messed with metering needles as well. I don't have a weber carb so I can't make any suggestions there.

FWIW: This year I came up with unbelievable readings. I failed the first e-test with CO readings of 6.2 % and HC readings of 430 ppm. The subsequent test netted
CO readings of (would you believe) 0.0% and HC reading of 7 ppm.
Hope this helps. Let us know how you make out.
John
John F

This thread was discussed between 18/12/2001 and 21/12/2001

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