Exhaust Soot Inside Coach

RickK80Eagle10 · May 10, 2010, 01:16:55 PM

80 Eagle 10 with 6V-92 Turbo

Previous owner wired bus heater/ac blower to run all the time. It seems this spreads a light layer of exhaust soot throughout the coach at the vent opening areas. Can it also be coming up through the engine floor access panels in the hall and rear lounge as well? Likely causes on where to start looking and possible corrections will be much appreciated.

Secondly, does the bus heater/ac blower help reduce engine heat like it does when a car overheats and you turn on your heater or can I put this back on a switch instead? I have a house furnace and AC unit that runs off the 12KW Kubota Diesel Gen so don't have to use the bus heat if it would reduce the soot. Thank you.

fe2_o3 · May 10, 2010, 01:22:49 PM

Do you have an exhaust leak?...Cable

Van · May 10, 2010, 01:46:22 PM

It would have to be a bad leak to pull it into the rear bay. Rick is it possibly coming from your Generator? My return air is in the center of the bus on the floor (2 grates), with fresh air inlets on both sides above the bogies. you can shut off the coolant flow to the core(s) via 2 ball check valves, one on each side, lower rear of the engine. also could pull the relay(s) in the rear elec panel,should be two, one for each blower (L/R).

RickK80Eagle10 · May 10, 2010, 02:06:11 PM

Thanks, Van. I will start there.

Lin · May 10, 2010, 02:06:34 PM

Yes, running the OTR heat will help cool the engine.

Jerry32 · May 10, 2010, 03:07:22 PM

sound like engine is blowing a lot of black smoke to make that soot. And if so then not enough air or turbo leak etc

RickK80Eagle10 · May 10, 2010, 03:38:48 PM

The engine seems to run very smooth and I have seen no evidence of any excessive exhaust smoke (grey, black or white) while operating or idling. Where does the heat duct originate? Is it possible it is sucking in exhaust from an opening or hole in it's ducts and then blowing it through the coach? The rear lounge gets the most soot - being closest to the engine I assume. What did you mean by not enough air? I will have the turbo checked as well. Thanks, Jerry.

robertglines1 · May 10, 2010, 03:49:07 PM

Van would know better that I but does your system have a fresh air (outside air)intake on side of bus that could be sucking bad stuff in???I know MCI and prevost do...sometimes the mechanical dampers fail and leave them sucking outside air all the time..had this experience

buswarrior · May 10, 2010, 05:57:31 PM

Is it soot, or is it fine black dust?

Have you cleaned the HVAC out? Lots of water and some of your favorite cleaner spray on the coils you can reach, in through the filter door, etc.

I'd be hesitant to decide it was exhaust, unless you can find a hole to the outside where there is some.

happy coaching!
buswarrior

Lin · May 10, 2010, 06:06:47 PM

Are you smelling diesel exhaust on the road? It would seem that if you have enough exhaust intake to cause soot, you should be able to smell it. Do you have a carbon monoxide alarm in the area in question? Even if there were not enough CO to set off the alarm, a digital one would show an elevated reading. Are you sure that the soot is from exhaust? Any unfiltered air intake will bring in general road pollution. It would accumulate around the register just as dust does on a heat or AC register. Maybe the PO did indoor barbecues or burnt a lot of incense.