Poor Mileage?

HammerDown

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Figured I'd ask here vs hijacking a thread.;Really

New BB injectors (2.5 years now) with maybe 8000 miles on them and I personally tested them to be good at install.
Baby Moose timed (few weeks ago) by "THE MAN" :hail:sly
Local mpg with a lot of easy local starts/stops = 10 :puke:

The only thing I can think of is 'maybe' an injector or few is ******* like a dog, but the engine is smooth as silk with no smoke unless the pedal is mashed :dunno

I'm not believing two gears jumped a tooth > sloppy loose timing chain in a old gasser yes, two gears, nope. Hmmm, maybe there's only 5 lbs of psi in each tire > or it's that old Pennzoil diesel oil I bought for $1 a qt. lol
 
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hesutton

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How's the speedo acting? Is it jumping around. Tires stock size or larger? If so, it (the odometer) my not be accurately measuring your distance for your MPG calculations. Any significat fuel leaks?

10MPG is certainly poor, something is up.

Heath
 

HammerDown

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Speedo is accurate >checked it with GPS.
Stock size tires
No fuel leaks

Maybe I need to switch out the winter to spring time air in the tires :Q
 

Diesel JD

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I remember that you used to always speak of relatively good fuel economy, to the point I was jealous. My latest fillup was 13.8mpg and that was on B100 (figure 5-10% mileage penalty) some slight fuel leaks and all in town(suburbia) driving. I don't consider that especially good but maybe I should stop complaining. Where did Mel set the timing....is it possible he made a mistake or something malfunctioned? 10 will not do, not even if diesel was $1.00 a gallon, which it isn't...
 

icanfixall

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My thoughts are a bad injecter. After 5000 miles the springs have taken enoughworking to have set. So pop testing them and shimming up the ones with sagging pressures in about the only thing I can suggest... Anyone can make a mistake on timing but I feel Mel is way beyond any kind of a common mistake. Did the mileage change when you had the timing set of has it been low for some time.... Hopefully fuel isn't leaking into the oil from the pump or the mechanical lift pump. Think back as to when the mileage dropped on you. Ask yourself what you did to the engine at that time.....
 

Agnem

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Sorry to hear this Ray. I thought for sure that number was going to come up for you, especially with the noted performance improvement. We can pop test those injectors some time if you want.
 

FORDF250HDXLT

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dont forget there is a lot more to do with fuel economy than just the engine.
jack up each tire,to check wheel bearings/brakes - insure a free spinning wheel.checking to insure the hubs are in the FREE setting,and while jacked up,insure the tire spins without rotating the axle.
tire pressure can really drain economy too.
with today's fuel prices,i'll be checking tire pressure weekly now.,rather than every other week/up to a month.
proper front end maintenance is key as well,such as ball joints/tire rods,etc. and keeping it all properly aligned.
insure the diffs,trans,t-case are properly flushed (use synthetics if affordable) on recommended intervals.

also insure the mechanical fan is disengaging.consider swapping out that old power/economy killing piece from yesteryear,for a more advanced dual electric setup.


14.63 MPG @ 44 tanks with my dually 4x4 dump setup (pretty much always hauling heavy.)

soon to see what injectors,proper timing(was retarded 2.5 degrees) and e-fans do to that number this year.:)
 
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badaceds650

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I think somewhere on here I thought you were saying you were running 255/75/16 which are taller then stock which would boost up your mileage a little bit from speedo being off but I could of been thinking it was someone else
 

HammerDown

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Thanks for the feedback fellas...yea this engine use to be in the mid/lower teens for local driving. Of course it's winter blend too.

Mel :hail set the Baby Moose timing from a low 5.5 to 9.5 and I wouldn't question his accuracy ;Really

Running stock size tires for a few years now, used 255/85R16 before.
All breaks are free, none dragging, hubs are free wheeling.
I'll double check tire psi

It could be a bad injector or few...I gave the borrowed tester back to the person I borrowed it from > and he ain't all that close by.

Where would I get shims and new copper washers anyhow? Crap...:frustrate
 

Compu Doc

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Not sure about the shims but the copper washers should come with a return line/injector install kit.
 

FORDF250HDXLT

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just curious.
was it your idea to go to 9.5 BTDC or Mels?
if possible,could you head back over and try 8.5?
just a suggestion.
if it was Mel recommendation to try 9.5,then disregard lol.as im sure he knows far,far more than i about timing.
 

Agnem

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Factory spec calls for + or - 2 degrees, so 9.5 is well within. With the crap fuel we get around here and Ray's truck being C6 powered, we were comfortable leaving it there. If anything I'd blame the fuel quality. The Moose Wagon gets about 2mpg worse in the winter than in the summer, and I believe it is the fuel blend behind the change. They don't post the cetane values so I believe they feel free to dilute it at will. That said however, I don't think fuel alone would cause Ray's low milage. Just not sure what else to blame it on, but possibly a tired torque converter. He does have quite a few miles on it.
 

Diesel JD

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More than likely the fuel economy would be worse with more retarded timing. I just got a matched set of injectors in mine and it's at -2.5 luminosity and it clatters pretty good there, but once I get all my leaks chased down I might advance it another degree or two to try to pick up some mileage.
 

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