Oil Vapor Separator and Smog Test

[rejogc]

I've just purchased a 77 spider and I'm getting it smogged here in California. CO% result is at Gross Polluter level. Here's the numbers:

15 mph / 2230 rpm %CO2=12.2, %O2=0.0, HC=185ppm, %CO=4.37, NO=534ppm
25 mph / 2374 rpm %CO2=11.8, %O2=0.0, HC=177ppm, %CO=5.04, NO=390ppm

I took it to a carburetor shop suspecting it was running rich. They cleaned out the air manifold which was blocked up with carbon build-up, replaced the check valve & tweaked the carburetor. They did nothing with the breather.

It looked good on their tester until the breather hose was connected to the air cleaner. Then little by little the %CO went up and up until it finally failed.

I'm focusing on cleaning the Oil Vapor Separator using the Crank Breather Kit from Vick Auto.

The carb guy believes the blow by is caused be the engine's old age. He thinks I should change to a heavier oil like 20-50 and add a can of Restore Engine Restorer. Then after a 100 miles or so, re-test. I'm kind of leary of additives.

Any thoughts anybody? What else could I do?

[rejogc]

I read a post saying the Oil Vapor Separator cleanup is a PITA so I'm skipping that for now. I'm gonna clean the PCV control valve in the carburetor to see if that'll do anything.

I changed my oil and added a can of Engine Restore. I had it retested at the carb shop and now the CO% is barely +/- in the Gross Polluter range instead of way in the Gross Polluter range like before. That's pretty cool stuff.

Thinking I'm gonna need a ring job at some time. Compression tested at 130+ lbs on 3 cylinders and 125 on another. I read somewhere in here that anything above 120 is good. Is that true?

Also read re-jetting the carb and retarding the timing by 3 degrees is the way to go. Can that get me down to reasonable CO% given how high it is now?

[So Cal Mark]

if the air pump is working, rejetting the carb should make it clean enough to pass. Does the car have a catalyst?

[majicwrench]

Mark certainly knows more about em testing than I do, but I dislike seeing folks mess with jets any more than they have too, when I did testing waaaaaaay back was always something else going on, unless of course, someone previously had installed bigger jets.
Not sure that retarding timing would have any benefit unless nox is way out.
Keith

[So Cal Mark]

Calif has tightened the standards, so the limits are now much lower than the limits Fiat designed to car to meet. For instance, most of the underhood tags specify 2.5% co settings. Calif standards are now 1.20% for that car. We change jets for the test, and change them back afterwards

[BEEK]

mark, can they require the vehicle to run cleaner than originaly designed? i would think that that would be able to be challanged at the state level

[So Cal Mark]

they keep tightening the standards every 3-6 months, gradually forcing older cars into scrappage

[rejogc]

Yes, this car has a catalytic converter the most recent PO installed. Before that the car had been sitting for 5 years or so. Besides a smog test, is there a way to check if the cat's in order?

The air manifold was cleaned out recently and new check valve installed. I just changed out the smog pump a few moments ago. For those interested the smog pump is used in many other GM vehicles. Mine was a re-manufactured Cardone 32-112. I got it from O'Reilly but it's pretty available.

I read a post here that rebuilding the carb is something a normal human can do (or even me, too). Can I re-jet with the rebuild or should I leave the whole thing to a pro?

[So Cal Mark]

you can easily check the catalyst if you have an infrared temp gun. Warm the cat up at 2000rpm for a couple of minutes, the outlet should be at least 100 degrees hotter than the inlet.

[majicwrench]

I would not recommend messing with the jets unless you know what you are doing. Am not sure the mechanic that recommended Engine Restore would be qualified either.
No reason to rebuild carb unless something wrong with it.
Keith