Bus Conversions and staying legal in California

windtrader · January 10, 2025, 04:06:55 PM

CARB, the Calif emissions police now regulate all heavy diesel vehicles in California. This includes our diesel powered bus conversions. If you own one in California, you already need to be registered and paid the fee to be in the CARB CTC program.

Your bus will be required to receive a pass on an emissions test called a snap or opacity test. Without this certificate, the DMW will hold registration as directed by CARB. If not already up to speed on this, here is a link to the next webinar about this program as it applies directly to bus conversions registered in CA.
https://content.govdelivery.com/accounts/CARB/bulletins/3c81f7d

All bus conversions NOT titled in California are free to visit here as usual as this applies to CA vehicles only.

muldoonman · January 10, 2025, 06:59:01 PM

Wonder how many 2 Strokes with miles would pass the snap or opacity test? My 1991 8V92TA with low miles was a clean runner but don't think it would even pass that test.

freds · January 10, 2025, 08:43:35 PM

Maybe with propane injection?

luvrbus · January 11, 2025, 06:47:27 AM

Snap tests are not much it has been in CA for years,the CHP did those on the side of the highway for years.They can pull a out of state RV over for to much smoke and give you a repair ticket. The ruling has people looking to buy throttle delays for the turbo 2 cycle engine they threw away years ago though,Az smog test all 2 cylcle DD in Maricopa County (Phoenix).The DDEC 2 cycle has no problem passing a snap test the ECM takes the right foot out of the picture

windtrader · January 11, 2025, 07:30:29 PM

Here is the opacity limits. Mine passed easily. Old buses are at 40%, I think I was around 7%. will post printout if I can find it.

luvrbus · January 12, 2025, 04:47:16 AM

Quote from: windtrader link=topic=37380.msg430711#msg430711 date =1736652629
Here is the opacity limits. Mine passed easily. Old buses are at 40%, I think I was around 7%. will post printout if I can find it.

Phoenix is at 50%,the tests are for revenue and tracking the old 2 strokes that fail are in need of help,the snap test is a no load test and the old engines do not smoke much with a no load,CARB will figure that out and require a dyno test.A few friends worried about it so I just closed the air gap on the governor for those it is not deleting or making changes it is legal it is a adjustment but they don't have any power till you reset the air gap

windtrader · January 12, 2025, 02:56:59 PM

Another way I heard that might work is just limiting the accelerator so it doesn't rev all the way up, so it is partial snap test. I have no idea if a tester needs to check all that out before running the test

luvrbus · January 12, 2025, 03:36:11 PM

Quote from: windtrader on January 12, 2025, 02:56:59 PM
Another way I heard that might work is just limiting the accelerator so it doesn't rev all the way up, so it is partial snap test. I have no idea if a tester needs to check all that out before running the test

They cannot check the air gap ,the N/A engines will pass the test fairly easy ,the turbo models can struggle with big injectors waiting for the turbo to spool up,that is why so many are hooking the throttle delay back up when it is working they won't take the (full) fast throttle causing the smoke

windtrader · January 14, 2025, 10:17:05 PM

Clifford,
so we are saying the same thing? air gap is how much throttle is open?

Iceni John · January 15, 2025, 09:36:31 AM

California has just now rescinded, or at least temporarily shelved, its plans to ban the future sale (and use??) of diesel trucks and railway locomotives in CA, due to expected pushback from the incoming Trump regime. Will this affect the present Clean Truck Check program or not? I don't know how much this change will affect our older bus conversions.

We live in interesting times...

John

luvrbus · January 15, 2025, 10:49:09 AM

Quote from: Iceni John on January 15, 2025, 09:36:31 AM
California has just now rescinded, or at least temporarily shelved, its plans to ban the future sale (and use??) of diesel trucks and railway locomotives in CA, due to expected pushback from the incoming Trump regime. Will this affect the present Clean Truck Check program or not? I don't know how much this change will affect our older bus conversions.

We live in interesting times...

John

They pulled the request because the EPA never would approve it (after 3 years) because it would have been nation wide not just CA

bs4104 · January 16, 2025, 07:50:08 AM

Don did you get a full year Compliance certificate from them?
Bruce

windtrader · January 16, 2025, 10:13:46 PM

Hi Bruce,

What I did as mandated was register the bus in the CTC (Clean Truck Check) database and forked over 30 bucks that I suspect will never be refunded.

That put me in compliance until the registration renewal time comes around and then a passing opacity/snap/acceleration test must be presented so DMV will issue the annual tag.

I'm not due for awhile so will just keep ears open on what transpires. I don't follow any social media that keeps up on the daily gyrations of CARB and the dance with the feds.

bs4104 · January 17, 2025, 08:56:46 AM

Has any one from Ca. been CARB tested? What was the out come? DMV is now holding up current year license now as of Jan 2025 renewals. Bruce

Dave5Cs · January 17, 2025, 09:03:27 AM

Read Windtrader above he has.