Author Topic: Making smoke  (Read 2245 times)

Offline Utahclaimjumper

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Making smoke
« on: October 01, 2006, 04:25:21 PM »
Question....my 8V71 is 'A' timed, N65 brown tag injectors, and starts and runs great. Problem....no smoke... I can be (and have) at 10 thousand feet pulling a 10 percent grade, foot full in it, and no trace of smoke. I live at 5600 ft. and travel at higher altitudes mostly so power is down. I added a home brew propane injection system that works very well and that helps on grades but it bothers me that Im not making full power. I have reduced the return orifice to 60 thou. and made no difference......so whats up?? poor fuel pump maybe???>>>Dan
Utclmjmpr 
 EX 4106 (presently SOB)
Cedar City, Ut.
 72 VW Baja towed

Offline buswarrior

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Re: Making smoke
« Reply #1 on: October 01, 2006, 10:45:15 PM »
Well..

First, be careful what you wish for... maybe it is set up well. You don't get a huge cloud unless things are out of whack...

Second, perhaps the exhaust is not getting to where you will really see it?

I was rather curious that the whisp of smoke that I was beginning to see on mine vanished on the way home from Arcadia two years ago.... turns out the tailpipe was also left behind on the I95 somewhere.... so it wasn't being presented to the side of the back bumper.

For simplicity's sake, I'd check for full throttle travel, both the adjustments and more sinister causes. When I got my bus, one of the mounting points for the throttle linkage under the driver's floor was flexing due to corrosion weakening the cross member. Ran great on the flat, wouldn't climb very well. Propped a board under it, and ran like a trooper until I got it reinforced. Darn thing didn't even flex consistantly! Boy, did that ever mess with my head!

Fuel pressure check, before and after the filters will quickly answer that question.

happy coaching!
buswarrior

Frozen North, Greater Toronto Area

Offline ceieio

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Re: Making smoke
« Reply #2 on: October 03, 2006, 03:06:56 PM »
Dan - my bus works the same way.  I have no idea what is in the engine for injectors, and what the timing is.  I too spend lots of time above 4000 feet (seems that's where I like to hang).  Lots of slow hours on hills, but never any black smoke, regardless of altitude.  My exhaust is in good working order and all that as well.

I guess the good news is that this setup should make it a little harder for me to hurt my engine given that the power knob seems to be set on "Extra Whimpy".

Craig - MC7 Oregon
Craig MC7 - Oregon USA

Offline Beatenbo

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Re: Making smoke
« Reply #3 on: October 03, 2006, 08:02:33 PM »
Boy that's a twist! I've spent years to get a bus that didn't smoke ::)

Offline Utahclaimjumper

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Re: Making smoke
« Reply #4 on: October 03, 2006, 08:31:07 PM »
 Im really not looking for smoke, just that sweet spot just before strong smoke, so Ill know Im at as much power I can make under those conditions. I have an air throttle and its opening fully, Ive adjusted the rack right to snuff, so back to the drawing board I guess>>>Dan
Utclmjmpr 
 EX 4106 (presently SOB)
Cedar City, Ut.
 72 VW Baja towed