BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: dolson on July 08, 2011, 09:08:14 AM

Title: on trip and getting blue smoke
Post by: dolson on July 08, 2011, 09:08:14 AM
I left Tulsa for Wyoming and about half way I started getting quite a bit of blue smoke when coasting downhill at speed. when I get back on the power the smoke clears up.  engine seems to be running fine and not using oil.  I have gained alot of elevation, is this a factor.  we are leaving Buffalo, WY today for Burgess Junction on hwy 14 whick is another 3200' higher.  Is this the sign of a potential problem or nothing to be concerned about.  I will have limited internet access on the mountain but will check back whenever possible.

Any thoughts would be appreciated, thanks
Title: Re: on trip and getting blue smoke
Post by: rv_safetyman on July 08, 2011, 09:32:05 AM
Don, I am not an expert, but the blue smoke under low or no throttle conditions seems strange.  Blue/black smoke should be from excess fuel and a diesel under no throttle basically shuts off the fuel.

At altitude you should see more and more black smoke for the same throttle position.  You have less air for the mixture and no turbo to make up the difference.

On a gas engine under deceleration blue smoke would mean that you are pulling oil past the rings or valve guides.  I don't think that is the case with diesels.

No matter what, make sure you air cleaner is not clogged.  Maybe try to buy a new one.  Most folks say not to blow out the filter, as you could damage it.  Assuming it is not oil bath, you could pull the filter and gently strike it to get the dust off the outside. 

I blow my filter out with a 1/4 inch ID hose with no connector.  The keeps the air impingement down a bit .  Probably still not the thing to do, but I have opened up the tubing to the turbo and it does not have any dirt/dust.

Jim
Title: Re: on trip and getting blue smoke
Post by: luvrbus on July 08, 2011, 09:43:32 AM
 "You got Jakes" 2 strokes will have blue smoke if you are using the Jakes alot 

good luck
Title: Re: on trip and getting blue smoke
Post by: dolson on July 08, 2011, 10:00:04 AM
yes clifford I do have jakes but have not been using them at all yet, when I do fip on the jakes while coasting the blue smoke stops.  after giving it a good look. it appears I do have a leak on teh exhaust side of the turbo and there is some oil present and its dripping a little onto the valve cover below.  even though I have gained a lot of altitude I do not have much black smoke.
Title: Re: on trip and getting blue smoke
Post by: TomC on July 13, 2011, 06:51:17 AM
Just like on a gasoline engine, when you get blue smoke it means oil burning. On no fuel coasting it could mean the valve guides are getting worn letting oil into the combustion chamber making blue smoke.  It doesn't take much oil to make smoke.  Probably eventually will have to dip into the engine if it doesn't stop.  Make sure you're running single viscosity 40 weight oil.  Good Luck, TomC
Title: Re: on trip and getting blue smoke
Post by: Just Dallas on July 13, 2011, 07:03:58 AM
I've been working with Doug via email and photos.
It seems the hot side of the turbo is leaking oil. I have been looking for the original part number for the turbo on his 6V92 but my parts manual is too old.
He's about 500 miles from PC Industries in Afton, WY. and although they aren't my favorite company, are close enough to ship overnight.

There are no tags on the bearing housing giving the part or model number, so if anyone has the correct GM part number from their MCI 102C3 manual it would be appreciated if you could post it. His bus is a 92 102C3 with MUI and HT740.

Thanks for the help!
Title: Re: on trip and getting blue smoke
Post by: luvrbus on July 13, 2011, 07:18:25 AM
PC Industries won't have the TV 7511 Turbo Dallas they order theirs from some outfit in MO and are junk IMO he would be better off at Smiths DD and probably cheaper  or he could call Tom at Turbo Re-Source in Lake Havasu  928-505-4610 he will ship to him

good luck
Title: Re: on trip and getting blue smoke
Post by: Just Dallas on July 13, 2011, 08:27:29 AM
Thanks Clifford, I got some stuff from PCI and it worked well, and some other stuff that was just pure yellow runny crap.
I was trying to get him the best, fast, price, and I don't have any connections in Wyoming except for PCI.

The last time I broke down in Wyoming was 30 years ago in Rawlins with a Cummins shiny 290 that ate the injection pump during a snow storm when they had the freeway closed. Damn, it got cold at the truck stop!

Quote from: luvrbus on July 13, 2011, 07:18:25 AM
PC Industries won't have the TV 7511 Turbo Dallas they order theirs from some outfit in MO and are junk IMO he would be better off at Smiths DD and probably cheaper  or he could call Tom at Turbo Re-Source in Lake Havasu  928-505-4610 he will ship to him

good luck
Title: Re: on trip and getting blue smoke
Post by: luvrbus on July 13, 2011, 09:00:47 AM
Yep I know Dallas me and the wife spent 3 days at Little America for road closer lucky we had the bus when they close the road that place changes menus and a hamburger goes from 3 to 6 bucks that was in the late 80's

good luck
Title: Re: on trip and getting blue smoke
Post by: TomC on July 14, 2011, 06:22:47 AM
Well that would be good news-an oil leak on the hot side of the turbo is relatively cheap to fix, rather then something worn inside the engine.  Good Luck, TomC