Author Topic: 6v92ta white smoke  (Read 9978 times)

Offline Jnbroadbent

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6v92ta white smoke
« on: March 18, 2013, 12:08:55 AM »
I posted this issue in my other thread but Id like to get more insight.

I know white smoke could be ANYTHING but maybe there are some tale tale signs I could look for. I'll also be getting an oil analysis but in the mean time...smoke smelled like fuel, it was thin for the first 10-15 mins but when we first accelerated it was thick smoke.

Its in a 102a3 I've been looking at owned by a large church. Has the reliabilt sticker on it. Can I call DD to find when the bus had a rebuild? It was owned by a charter compan not grey hound.

White smoke on start up, seemed to clear up after about 20-25 mins only going around the block once, didn't take it on the high way to really open it up. One of their mechanics decided to take it for a spin and ran out of fuel? System was re primed and all is well but maybe junk got by the filters. Shut it down for about 20 mins then restarted it to move it and more white smoke.

I know my 8v71 runs hard so I don't want to get something I can't rely on!

Thanks for any info.
Jon
1980 Mc9 w/ veg oil
8v71
Jacksonville Fl

Offline CrabbyMilton

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Re: 6v92ta white smoke
« Reply #1 on: March 18, 2013, 05:14:56 AM »
White smoke usually means you are burning oil. Either that or your engine just picked the new pope.

Offline 5B Steve

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Re: 6v92ta white smoke
« Reply #2 on: March 18, 2013, 06:17:01 AM »

   A low cetane fuel will also create white smoke.


  Steve 5B.....

Offline Geoff

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Re: 6v92ta white smoke
« Reply #3 on: March 18, 2013, 07:46:42 AM »
White smoke in 2-stroke detroits is unburned fuel (not water).  It could be from the injectors or low compression.  You need a Detroit Diesel compression tester to figure out what the problem is.  I would bet low compression.  The white smoke goes away as the engine warms up and the compression goes up.
Geoff
'82 RTS AZ

Offline TomC

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Re: 6v92ta white smoke
« Reply #4 on: March 18, 2013, 08:01:36 AM »
White smoke = non ignited fuel. Blue smoke = oil burning. Black smoke = too much fuel being ignited for the amount of air. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline chessie4905

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Re: 6v92ta white smoke
« Reply #5 on: March 18, 2013, 12:59:35 PM »
It could be from several starts without driving it. If you take it for a half hour run at highway speed and see if it clears up. I'm assuming the coolant level and oil level are normal. You could loosen the oil drain plug a couple of turns to see if any water comes out with the oil. Wait overnight without running the engine though before you check it.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline Sam 4106

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Re: 6v92ta white smoke
« Reply #6 on: March 18, 2013, 01:15:32 PM »
Jon,

Unless you absolutely HAVE to have that bus, you might be better off looking elsewhere. The recommendation in the past has been to avoid church buses. Lack of maintenance is often the problem with low budget church buses. It can cost a lot of money to bring a neglected bus up to a satisfactory level of maintenance. If you have to do engine work in addition to everything else that can need work it can be quite costly and demoralizing.

Good luck with your search, Sam

1976 MCI-8TA with 8V92 DDEC II and Allison HT740

Offline Taibob

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Re: 6v92ta white smoke
« Reply #7 on: March 18, 2013, 01:25:16 PM »
 
Came from a large church
white smoke
 Yeah, I would check out that "new pope" thing

just saying.
84 mci 9  8v71n N70 Jakes 740 auto 2 Slides    BC/AB Canada

Offline John316

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Re: 6v92ta white smoke
« Reply #8 on: March 18, 2013, 02:52:32 PM »
We could nail down where he is from....Detroit ::)

Now that scares you doesn't it ;D :o ;D
Sold - MCI 1995 DL3. DD S60 with a Allison B500.

Offline akroyaleagle

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Re: 6v92ta white smoke
« Reply #9 on: March 18, 2013, 03:59:17 PM »
If you start a DD in freezing weather without a block heater it will belch a lot of white smoke!

Warm it up on a run, then shut it down and try it while it is warm. My guess is, the problem will go away.

A lot of folks that don't live in cold areas will overthink this.

Probably a lot of truth about lack of maintenance by current owners though.
Joe Laird
'78 Eagle
Sioux Falls, South Dakota

Offline HB of CJ

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Holy Smoke?
« Reply #10 on: March 18, 2013, 05:01:59 PM »
"While the organ peeled potatoes"...

"and the choir rendered lard"...

"while the preacher was a preaching'...

'somebody set the church on fire"...

"Holy Smoke" the preacher shouted"...

"and in the rush he lost his hair"...

"Now his head resembles heaven"...

"for there is no parting there"!

the end.  HB of CJ (old coot) :) :) :)

Offline CrabbyMilton

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Re: 6v92ta white smoke
« Reply #11 on: March 19, 2013, 03:49:21 AM »
I have to remember that one. Thanks for the laugh.

Offline luvrbus

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Re: 6v92ta white smoke
« Reply #12 on: March 19, 2013, 07:23:25 AM »
You are not getting much help,most of the time low compression like Geoff said is the problem but injectors leaking can cause a problem with it smoking that bad take it to a dealer or run it hard for 50 miles see if it cleans up
Life is short drink the good wine first

Offline Lin

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Re: 6v92ta white smoke
« Reply #13 on: March 19, 2013, 02:25:39 PM »
Whatever the issue turns out to be, it is a warning for you.  You are looking at a bus and seeing a problem right off that the owner did not even care to look into.  This would seem to point to a complete lack of concern for maintenance.  It could be likely that there are other issues that they have ignored also.  I think that churches have a tendency to buy a bus, run it down, and sell it.  For their use, it is probably cheaper to buy another used bus than to fix the one they have.  Since you are going to convert the bus, you don't have that luxury.
You don't have to believe everything you think.

Offline TomC

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Re: 6v92ta white smoke
« Reply #14 on: March 20, 2013, 06:35:47 AM »
If the temp is above 50 degrees, the engine should cold start with no problems and no smoke. I just started my 8V-71 for the first time this year and it put out a bit of black smoke (big injectors) then no smoke at all. Started like it had been started yesterday-2 compression hits and running. Good luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

 

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