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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Gordie Allen on November 13, 2015, 02:57:07 PM

Title: Black smoke and no power
Post by: Gordie Allen on November 13, 2015, 02:57:07 PM
We were heading to California with our 4104 (third trip to CA). Got 20 miles from home and the power just suddenly went away. Like I shut it off. Engine didn't quit, just puked and blew grey smoke. It idles fine even on high idle. I can rev it 2-3 times with slight white smoke. If I rev it to 1500 rpm it holds for about two seconds and then just dies down blowing dark smoke. It doesn't quit, just won't hold rpm's. If I let it idle for 10 seconds it has normal throttle response for 2 seconds and then dies down again. Had it towed to a big shop and drove toad back home. Is this something simple like fuel supply, or is it likely to be something serious? Hoping to hear from the shop tomorrow. How bad is it?
Title: Re:
Post by: daddyoften on November 13, 2015, 03:01:14 PM
My first guess is it sounds like a possible turbo failure.  Check your air cleaner and make sure it's not plugged
Eric

Sent from my XT1254 using Tapatalk
Title: Re:
Post by: eagle19952 on November 13, 2015, 04:04:02 PM
Quote from: daddyoften on November 13, 2015, 03:01:14 PM
My first guess is it sounds like a possible turbo failure.  Check your air cleaner and make sure it's not plugged
Eric

Sent from my XT1254 using Tapatalk

yup....air or fuel filters first.
turbo next.
salted fuel...??
Title: Re: Black smoke and no power
Post by: RJ on November 13, 2015, 04:09:19 PM
Eric -

No turbo on Gordie's 4104, it's a normallly-aspirated inline 6-71.

Gordie -

I agree with Don - fuel filters first, as it sounds like it's not getting fuel.  Might also check some of the fuel lines for a collapsed hose.

FWIW & HTH. . .

;)
Title: Re:
Post by: daddyoften on November 13, 2015, 05:31:47 PM
Sorry, can't see signatures in tapatalk

White usually means lack of fuel, black is too much fuel or not enough air

Sent from my XT1254 using Tapatalk
Title: Re: Black smoke and no power
Post by: chessie4905 on November 13, 2015, 11:38:27 PM
Sounds like the flap on the intake closed. Check it and see if it needs reset. Usually only happens if you hit emergency stop, but some have reported it vibrated shut becaused it wasn't reset fully last time.
Title: Re: Black smoke and no power
Post by: OneLapper on November 14, 2015, 12:35:51 AM
Quote from: chessie4905 on November 13, 2015, 11:38:27 PM
Sounds like the flap on the intake closed. Check it and see if it needs reset. Usually only happens if you hit emergency stop, but some have reported it vibrated shut becaused it wasn't reset fully last time.

I agree with Chessie.  Sounds like the shutoff flap is doing it's job. 

Title: Re: Black smoke and no power
Post by: luvrbus on November 14, 2015, 12:44:54 AM
Gordie knows about the shut down it cost him one time  ::) sounds like the blower drive is stripped
Title: Re: Black smoke and no power
Post by: Scott Crosby on November 14, 2015, 01:24:51 AM
There is a blower drive gear on eBay that's in Michigan for $10.  Might be the correct one, that's what my IL671 looks like. http://www.ebay.com/itm/NOSTALGIA-Blower-Supercharger-SNOUT-DRIVE-7-3-4-SHAFT-7-8-COUPLER-671-6-71-/181767881427?hash=item2a5235c2d3:g:W6gAAOSwBLlVc5a~&vxp=mtr (http://www.ebay.com/itm/NOSTALGIA-Blower-Supercharger-SNOUT-DRIVE-7-3-4-SHAFT-7-8-COUPLER-671-6-71-/181767881427?hash=item2a5235c2d3:g:W6gAAOSwBLlVc5a~&vxp=mtr)
Title: Re: Black smoke and no power
Post by: Gordie Allen on November 14, 2015, 10:16:12 AM
OK,  I have a confession to make. Clifford was right. I had the bus towed two years ago because it just died. It was the emergency air shutoff flap. This time it didn't die, but I should have checked that the first thing. So I win the dumbest bus nut award. I drove over to the truck shop this morning. Told them what I thought was wrong. I went back, fixed the shutoff and told them thank you for their time. They didn't charge me anything, probably because they felt sorry for my mental deficiencies. I do appreciate everyone's input. This is my support group.
Title: Re: Black smoke and no power
Post by: Scott Crosby on November 14, 2015, 10:52:18 AM
Mine self deployed at near 70mph on the highway a few weeks ago...

It was spewing massive amounts of oil from the air box... I thought I had major damage until I noticed it slid off the catch.  It ripped a hole in my intake air hose coupler.  I left a strait line of oil on the highway for probably a mile and a good couple of quarts when I parked on the ground drained out of the air box.... I let it drain the oil out of the air box for a few min then started it right up and drove it home.  Since then it's got a few thousand miles and the blower seals seem fine.  No oil consumption or smoke.  The blower had new seals with only about 8 mo and a few thousand miles on them.  I've been carrying a blower rebuild kit just in case. 

It was running so rough and smoking and it wouldn't shut down with the fuel off lever so I went to flip the flapper and that's when I noticed it was tripped so I opened it up.... then the rpm shot up and I nearly pooped my panties.  I closed it again and it shut down.   If I had pressed the clutch in right away that would have helped with the oil sucking so for others that may experience a total loss of engine power with black smoke think about pressing in the clutch right away....  My flapper is now zip tied open.
Title: Re: Black smoke and no power
Post by: OneLapper on November 14, 2015, 11:10:43 AM
Don't think twice about it!   You've already had your "mishap" for this trip!  It's smooth sailing and rum smoothies for the rest of the ride.

Title: Re: Black smoke and no power
Post by: pabusnut on November 14, 2015, 11:24:14 AM
Gordie,

You can't possibly win the dumbest busnut award!

I know a guy who forgot to unhook his electric cord as he was moving his bus about 15 ft back from his garage, and ran over the cord with the front wheel which ripped it right out of the bus, and took the bay door to a 45 degree tilt with it!

Shortest, most expensive trip in history!! :'( :'(

Yes! it was yours truly!!! :) ;D  I did give Luke a good laugh when he found out why I needed the parts!

Steve Toomey
PAbusnut
(now a believer in pre-trip checklist---NO MATTER HOW SHORT THE TRIP IS!)
Title: Re: Black smoke and no power
Post by: HB of CJ on November 14, 2015, 12:05:04 PM
The infamous emergency trip lever event.  I will NOT tell you a short story when three nice houses got their roofs burned off in a city in the Southern CA central valley when a series of non fortunate events happened including an emergency trip lever being tripped non knowingly.  Put that responding fire engine on scene immediately out of service thus delaying water being put on the fire.

Then the fire went to heck from there.  Seems nobody knew the signs and symptoms of a tripped emergency air shutoff nor had any idea how to reset it.  Seems the new young guys could not even steer.  "No, we don't teach that any more in the fire academy".  Well, perhaps they should have.  The earlier generation were taught that stuff.  The new guys can't manually shift gears either.  Yikes!
Title: Re: Black smoke and no power
Post by: Scott Crosby on November 14, 2015, 12:32:21 PM
A shut down flapper can suck a lot of oil out of the blower....

Title: Re: Black smoke and no power
Post by: Dave5Cs on November 14, 2015, 12:37:24 PM
Look on Craig list, the majority of classic cars for sell at 25 grand and up are Automatics....... Uhhhhh. who wants a 57 chevy automatic.

Gordie thank goodness you did this because now I am no longer on the top of the idiot list, LOL
When we came back from the Q last year I forgot to put my S-10 LS pickup in Neutral after we stopped 200 miles from home and I dragged it about 400 feet squealing like a pig. I realized what it was and pulled over and put it in neutral. :'( It seemed fine until at the ranch the next day it started knocking in the lower end. I left it idling and had to go into the barn for something. When I came out it was no longer running. Motor barley turned over. When I stripped it down it was seized.  :oI pulled it apart and found spun bearings (mains and Rods). Being I had it for 6 years and only paid 500.00 for it decided to pull it to the wrecker for scrap.
Got me a nice little green 98 Jeep TJ now.  ;D

Dave
Title: Re: Black smoke and no power
Post by: Gordie Allen on November 15, 2015, 11:12:06 AM
Yeah, I'm working on departure check list, arrival check list, and bus on the side of the road list. ;D
Title: Re: Black smoke and no power
Post by: bigred on November 15, 2015, 11:35:15 AM
Does the 8V92 have an emergency shut down switch? If so ,where is it ??
Title: Re: Black smoke and no power
Post by: HB of CJ on November 15, 2015, 12:15:31 PM
Some help here please.  I think (think) the very early 8V92N MUI Detroits may have had the manual emergency air shutters.  I do not think the later ones did.  The fire screw up with the emergency shut down involved an old American LaFrance engine with the older DD MUI 8V71T engine.
Title: Re: Black smoke and no power
Post by: TedCalvert on November 15, 2015, 12:32:06 PM
Dave5Cs:

So, are you saying that dragging the toad, tires skidding, maybe turning the engine over with no oil pressure seized the bearings?
Thanks for sharing your misfortunes; we can all learn from it.

Ted.
Title: Re: Black smoke and no power
Post by: solodon on November 15, 2015, 03:47:44 PM
Not to be difficult, but it seems that most engines have oil  pumps that will turn if the engine is turning.  Generally connected in some fashion to the cam and/or crank.  If the engine turns the pump turns so it should have had some oil flowing.  Just saying.  Don
Title: Re: Black smoke and no power
Post by: kyle4501 on November 15, 2015, 04:06:42 PM
Quote from: solodon on November 15, 2015, 03:47:44 PM
Not to be difficult, but it seems that most engines have oil  pumps that will turn if the engine is turning.  Generally connected in some fashion to the cam and/or crank.  If the engine turns the pump turns so it should have had some oil flowing.  Just saying.  Don

If it was in reverse, wouldn't the motor turn backwards . . . .
Title: Re: Black smoke and no power
Post by: Dave5Cs on November 15, 2015, 04:36:45 PM
Was in 1st gear. don't know for sure that did it but it was in pretty good condition before that happened. Tires were screaming pretty good. didn't realize it coming out of the rest stop into traffic and the Bus engine accelerating until we got into 2 gear. Also lost my light box on the bus truck hookup and had to let it idle the rest of the way home for tail lights. So 6 of one ya know!...