This question is for you diesel guys. Here in Arizona we are required to run our motorhomes through emissions testing annually. Until last year, I would always drive up onto a set of rollers and run the engine at a constant speed as indicated on the speedometer. Last time I went they changed it up. Instead of the rollers they wanted me to run the engine wide open in neutral. I refused to do it and instead, ran it up to the governed speed for this engine. What's the deal? Would it be OK to floor it in neutral as the attendant demanded? Thanks.
jor
For one or two seconds-- OK as long as not more than 200 RPM over governed RPM.
Longer-- I wouldn't personally do it. And, no idea what a no load test very high RPM test would show???
They do that test up here for all diesels. They put an opacimeter in the exhaust and do a "snap throttle" test where they floor it and measure the output during acceleration and at governed rpm. They hold it at rpm for a few seconds until the computer says stop. No other option here.
Before going in for that test, probably a good idea to do a couple of WOT 0-60 MPH runs to clear the soot out of the exhaust.
That's BS. I'd move to another state. 8)
FWIW: when I go to the specs for our C8.3 at Cummins QuickServe Online, it shows the data listed below. Sounds like what the smog cops want to see is called "HIGH IDLE". On my coach that is 2760 RPM. Don't think I would want to rev our engine to that speed, although theoretically it would not come apart. Don't care to test the theory...
ADVERTISED HP: 300 @ 2200 RPM
GOVERNED HP: 285 @ 2400 RPM
TORQUE PEAK (lb-ft): 820 @ 1300 RPM
HIGH IDLE: 2760 RPM
GOVERNOR BREAK RPM: 2450
You could relocate to Ajo, no testing needed, at least, we were not asked to re-test for the past three years. ^.^d
Different states, different laws. Cal. no motorhome smog testing required, at this time.
I have/had seen a lot of overfueled diesel pickups in Arizona. Black smoke from tailpipe. Also other interior west coast states.
Bob,
All the over fulled PUs should be pulled over and inspected on the spot. No waiting for a bi-annual smog inspection. They give all diesels a bad name.
Not just black smoke but a lot put out clouds of the stuff.
Pierce
I have never ran my engine up to the governor like the ask. I just rev it to about 1500 rpms for about 2 seconds at three times and it's done, they are just looking black smoke. However I agree it's a pain in the butt to have the inspection done ever year. They use to test motorcycles until Arizona realize no one rode motorcycles in 110 summer heat when pollution was high, motorhomes should be treated the same.
Steve
3208 Cat engines took up to 5 seconds to adjust after a hard throttle input. Normal to smoke for five seconds
Amazing that cali of all places doesn't test motorhomes. I thought they were getting to start emission testing household pets soon.
You are correct about a crazy loophole. All our weedeaters and lawnmowers have to have CARB stickers and no mater what year your diesel truck is, it must be CARB compliant. Maybe the people that write these rules own motorhomes.
I have to have an outside California address to buy the deck sealer for my crane and many things Home Depot sells won't ship to Ca.
I would imagine it's all over: up in WA, if you live in a lttle podunk county (like we did) there are no tests. But if your coach is registered in the Seattle area, testing. I don't know what the cut-off date is; in all the years we had SOB coaches, nobody ever asked! ^.^d
I go through it every two years. Commercial is every year. They only did the rollers for the cars and light trucks up here. I have not heard of one breaking during the test.
No more rollers in Ca for OBDll cars.
Do they test small breweries for their co2 emissions, it's a boatload number, I bet not. Same for the Napa valley wineries. And expect you to risk your engine because your in their target group. Does the local metal cutting shop that uses 6000 gallons of liquid nitrogen every 3 weeks to blow out the kerfs get a black eye?
We are living in Absurdistan. It's not just Ca. Driving from south Tx. to Austin at night the back way, the natural gas flares from oil wells in the Eagleford play lit the sky with flames and smoke. Millions, most likely Billions of BTUs of natural gas being flared off daily. Like driving through Mordor. The next day I was having the tailpipe on a 2 liter vehicle sniffed for emissions. The individual is an easy target while we gag on the excretions of unregulated industries.
Took the rig through Arizona emissions testing on the way back from our recent trip. They require the "snap acceleration" method on all heavy duty vehicles now. The instructions are to floor it three times in a row while they measure the opacity of the exhaust. I just hit it up to about 2300 revs on each go. No problem. The old 8.3 is a clean runnin' little guy with an opacity percentage of 2.2. The max is 40. It's actually easier than the old method which involves trying to maintain a constant speed with the drive wheels on rollers like a dyno.
jor
The purpose of the test is to test the "Puff Limiter". If it goes wrong the engine will put out a big puff of black smoke when the throttle is snapped open. Pretty pointless on the M11 as it's a clean engine. Mostly used for trucks. Don't go past the upper rev limit. If the examiner asks just show him the Cummins specs.
Keith
Up here in Payson, I sure see many beefed-up pickups that smoke ( lots!) upon a quick take-off!
As a libertine sort. I'm not one for "over" regulation. But, "rolling coal" should be a crime and carry a high fine.