Failed emissions

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amaurer

amaurer

10 Year 15 Year
Joined
Sep 2, 2007
Threads
373
Messages
4,438
Location
Longmont, CO
BJ73 (rotary pump) failed emissions... I knew it was smokey, but I was surprised at how far off I am. Injectors are new (1 year), timing was checked and is spot on. Air filter is OK, I think. The big thing is that I'm at 5200' elevation, not much I can do about that. Opacity requirement is 40%:

40mph 71%
50mph 60%
60mph 55%

Thoughts?
 
What kind of smoke? If it's black from high altitude, perhaps dialing back the fuel a bit would help.
 
Yeah, its black. This truck was [black] smokey at lower altitudes too, its just always had darker exhaust than my inline-pumped 3B.

I'm not sure where the fuel screw is on the rotary pump though. I've read the FSM and it seems like it doesn't really have one? More like you just adjust the throttle stops.
 
A couple of easy changes may help to pass:

Remove air filter just for the test

Adjust the throttle stops to limit the throttle opening - ie, reduce fuel

Find a test station at the lowest altitude possible

There was a fuel additive to reduce smoke I have seen, but never used

I don't know this type if IP, but there should be someway to reduce fueling. Maybe a recalibration if your only using it above 5,000'

All I got
 
When ever my cruiser had problems with testing it was due to the testers driving style. Limit the fuel and you should be good. I use to limit my fuel so much they would get frustrated and couldn't do the road test fast enough and only do the high idle test. You could run a cetane additive as well.
 
Sorry for that, first time I had to have my HJ at 4100 rpm for three seconds was just a big mental heart-attack.
But after 4 years / 280.000 kilometres it still has no problem whatsoever with the European full throttle test (far below 2.0 max, 2.5 for turbo)
What I know of, to limit the particles:
-start engine and spray water in exhaust,also with high pressure=loads of black stuff removed
-use shell expensive diesel (makes land-rover test go from 4 to 2.0)
-use 30 % veggy oil or more= a lot less soot
-use 2 liter of atf in the diesel to clean inside
-use 2 liter of gas in diesel to clean inside
-rev the crap out of it to clean engine, lol is the word crap allowed nowadays :bounce::flush: :clap:
-make sure engine oil is new, fuel/air filter new.
-fill new filter with additive but that is a trick that lasts for a minute (but is done here)

If that does not help your engine needs a rebuild?

Good luck, If all specs are factory it should pass for many years.
 
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With boost compensator
 
Amaurer,

What changes did you do to pass? (assuming you did pass)

I just took my 3BII powered BJ75 in and failed opacity as well.

The tech typed in my VIN about six times and the machine kept giving him the middle finger (invalid VIN), not sure what he finally entered to get the machine to do the test. As this engine was never spec'd for our markets, can the Air Quality Board requirements even be met by this engine?

No speed test, just a few stomps on the throttle pedal with the sniffer in the tail pipe. I think the limit was .5 and I had .84 but I'm not sure and I don't have the paperwork with me.

I'd like to be systematic and change only one thing at a time until it passes, but I'm not sure how many times the test station will re-test.

I will be replacing this engine soon, so not sure how much time/energy I want to spend on it. But I am curious as to a fix...I have noticed this engine smokes worse than my last 3B, with the inline pump. If I accelerate (or try to) too fast, it smokes bad, if I'm easy off the line, it's barely noticeable.

Thanks,

Dan

P.S.

I don't think Biodiesel is available to the general public in Boise; I just did a quick search and only found it at two stores and you have to be a member...not sure what the membership requirements are, but I think the places that sell it are for commercial vehicles.
 
My buddy who runs one of Cat's biggest dealers suggest to their customers who must get opacity - smoke tests, to get the engine and exhaust good and hot on a highway speed run as close to the test as possible.

There are some additives that claim to reduce smoke, not sure of they work or not.
 
Thanks for the response.

I think my game plan is to run some Diesel Purge through it, clean the tail pipe, change my air filter & reduce the fuel supply...reading the fine print from the testing station, I get one free re-try.
 
You could remove the air filter just for the test!
 
doug720 said:
You could remove the air filter just for the test!
Click to expand...

If your air filter has enough restriction to make the difference, then you need a new (or bigger) air filter.

Hot engines burn cleaner than cold engines. Past that you need to either get more air in (adjust valves, clean intake etc) or reduce fuel.
 
Dougal said:
If your air filter has enough restriction to make the difference, then you need a new (or bigger) air filter.

Hot engines burn cleaner than cold engines. Past that you need to either get more air in (adjust valves, clean intake etc) or reduce fuel.
Click to expand...


But every little bit helps...and this is easy
 
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