TheSamba.com :: View topic

Tue Dec 09, 2003 11:52 am

Hi there, I'm new to the Aircooled scene and Im having some troubles with the dreaded BC aircare.
I own a 1978 Westy with a rebuilt 2 litre twin carb engine (I've been told that it's 72-74). It has failed BC air care twice in the past few weeks due to Co2 immissions (while driving, it passed at idle). I changed the oil, put in a fuel cleaner, filled up with high octane fuel and drove on the motorway for a while (to heat up the engine ) before my last test as I was told they would all help reduce my immissions....but alas... : (

I took it to a mechanic but he seem to think that it would be near impossible to pass with twin carbs. However the bus was aircared for the last last year. I bought it in June and it had 6 months remaining on the aircare, it runs well so I'm stumped.

Does anyone have any suggestions for a fix, or the name of a good mechanic in the Vancouver area that will be able to get me back on the road,
Many thanks,

Seamoose

Tue Dec 09, 2003 1:15 pm

That's a bummer that program is still in effect. I lived in Vancouver in the summer of 95 and had to air-care my bus in order to change to the local insurance zoning. When I went for the test it was largely a mystery to me. At the time I just thought it was easy to pass an old VW because the stardards were lax but I guess not. Having been through the smog system here in California with my bus perhaps I can provide some insight into your problem.

First, are they testing the emissions based on the limits the factory specified for keeping your bus in tune or is there a more general catagory that applies to VWs by age and vehicle weight? This is important because as VW went through the 70s the busses ran leaner and leaner to the point where the 79 CA model was running "head burning" lean with an O2 sensor monitoring the emissions.

For a 78 bus the CO volume needs to be 1.5% max. If you swap carbs on that engine it will run much richer than fuel injection so it's easy to see why you failed your test. Down here, based on the pass/fail tables the standards limit FI CO emissions to ~2% whereas carbs limits were higher around 5-6%.

My question for you is how rich to do you have to be before you fail? What did your report say? I think it's possible to get the engine to pass the test although it will probably run poorly and kill it if you continue to run it that way without readjusting it after the test and breaking the law.

Tue Dec 09, 2003 2:44 pm

Hmmm, down here in the states you are exempt if the vehicle is over 25 years old (glad I have a '72 :) ) or they will pass you if you can prove you spent a certain amount of money on repairs, regardless of the test results (used to be $100, I don't know what it is now. Here in Ohio it is done on a county-by-county basis, and I no longer live in a county with emissions testing...) Here's a story about it that I found pretty funny:

http://www.inertia.org/acvwjyro/echeck/advent.htm

Tue Dec 09, 2003 3:17 pm

It depends. Some places it's 25 years, other places like CA it's 30.

I just found all the info I was looking for at the Air care website. The information was quite surprising. At idle the standards are far less strict that CA but standards for the acceleration test on the dyno as stricter.

The idle test is based on vehicle weight and the other test based on engine displacement. And the tests are twice as often. Ug.

What did your report say?

Tue Dec 09, 2003 4:39 pm

That story is great!

Tue Dec 09, 2003 4:52 pm

Hey Guys, thanks very much for the research and input. I'm at work right now and don't have access to the aircare report but I'll post the details as soon as I get home.
Excuse my mechanical ignorance as its the first vehicle I've ever owned.
I'll gather as much info as I can for you experts and Im sure you can help me figure this out.

Tue Dec 09, 2003 7:15 pm

Ok here's the lowdown on my results from 2 weeks ago

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-
Driving Test----Allowable------Result
HC ppm------208--------133
CO %-----1.98-------3.82
NOx-----2382--------875
------------------------------------------------
Idle Test----Allowable------Result
HC ppm----424------------- 140
CO %----4.67------0.28

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-

and heres the results that it passed with for the previous owner in 2002

Driving Test----Allowable------Result
HC ppm--------208--------133
CO %-----------1.98-------3.82
NOx-------------2382-------875
------------------------------------------------
Idle Test----Allowable------Result
HC ppm------424----------140
CO %--------4.67----------0.28
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-

So she passed at idle but failed the driving test (which is at 40kph for 2 mins). As i said before I've been told that its got a rebuilt 72-74 2ltr twin carb engine, that I'm pretty sure has around 10,000 k's on it. I know the limits are lower for older vehicles so mabye I should ask them if they can test it with 74 limits (whether or not that will work I dunno). All advise is welcome that would help me b(ch)eat the system ; )

Sure I hope Zeek and Elmo have moved to Vancouver I could do with some comedy at the test centre.

Thanks again for the help

Tue Dec 09, 2003 8:13 pm

You posted the same results for both tests. If I were you, I'd talk to a local aircooled shop about this, as they should be familiar with the test protocols in place. Jeremy

Wed Dec 10, 2003 12:25 pm

I don't quite understand the numbers. Did you type it in correctly? 0.28% CO for idle is so ultra-lean the engine should be misfiring. Hard to argue when you're passing that one I guess but still...

I'd email John Connely at aircooled.net for his advice on how lean you can set your particular carbs.

Wed Dec 10, 2003 3:00 pm

Sorry about the mix up with my figures :roll:
I pasted them in from an excel sheet and botched it up
So here goes again

my results from 2 weeks ago
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-
Driving Test----Allowable------Result
HC ppm------208--------133
CO %-----1.98-------3.82 --->Fail
NOx-----2382--------875
------------------------------------------------
Idle Test----Allowable------Result
HC ppm----424------------- 130
CO %----4.67------0.10 (even lower and not a typo!!)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-

Results that it passed with for the previous owner in 2002
Driving Test----Allowable------Result
HC ppm--------208--------61
CO %-----------1.98-------0.57
NOx-------------2382-------1364
------------------------------------------------
Idle Test----Allowable------Result
HC ppm------424----------194
CO %--------4.67----------0.11
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=-

Thanks for the help ratwell :D I'll pass this info along to aircooled.net and try and find some one in Vancouver that can make the adjustments for me....Have a good one!

(O/_|_\O)

Wed Dec 10, 2003 3:21 pm

Good luck with it. Hopefully you can find a balance that will pass. Generally when %CO and HC ppm are low NOx goes high because of the increased combustion chamber heat. If you don't have any sort of EGR attached to combat it you may fail the NOx test.

Wed Dec 10, 2003 4:18 pm

Have you talked to the previous owner about this yet seamoose? Maybe they did some adjustment for the test, and forgot to tell you. Good Luck!

Wed Dec 10, 2003 7:07 pm

Might be some ideas you can use from here.... good luck!

http://www.recarbco.com/technical/smog/smoginfo.html