Poor fuel miliage ??

[lincoln]

Hello,
I just replaced the enjectors on my 94 turbo diesel with rebuilt stk enjectors. The truck starts great has good power and a slightly rough idel. It was getting 15 mpg and sometimes 16-17 and 12 pulling 5K trailer. Now it gets noticably worse miliage. 12-13 empty and I mean babying it and 9-10 pulling trailer. I notice comming home at night there is a pretty good stream of smoke coming out,I can see from the headlights behind me. I can't find anyone around me that I trust to time it? Could this be a timing issue/ Thanks So Much

[OkieGringo]

Yes, timing will change when you install new injectors. New injectors, with new springs, will open later and cause timing to be retarded.
From my "library". OkieGringo
Retarded timing will cause white smoke, too advanced timing will give you black smoke. Remember advance is top of pump to pax side, retard is top of pump to drivers side, do not change timing when engine running, tighten all nuts before starting. 1/32" or pencil leads width is about 3* so 1/8" is about 12*, way to far at one time.
If it starts and runs really quiet I would suggest your timing is retarded slightly.
The following info was posted as a guide for retarded timing, remember do not move the injector pump engine running and always tighten the IP before starting.
*****
The marks on the pump to housing are only accurate if it is the original pump from the factory. Your timing is a few degrees retarded. Turn the injection pump 1/16" to the passenger side (measured at the pump to housing flange) That's about 4 deg.
If you don't see white/blue smoke on acceleration your within 3 to 4 degrees retarded (white smoke = more than 4 retarded) low power, poor milage and prolonged starter engagement. If you see black smoke with heavy combustion noise, you are 4 or more deg too advanced. Glow plug damage can occure and milage will suffer. You know you have it when it starts quickly and gets good milage.

If you want to see if the timing should be advanced you could hook up a 12v jumper to the timing advance when the engine is warm, if it idles better or runs stronger then you can do an advance 1/16", then try it again to see if more is required.

[lincoln]

are there just two nuts to loosen to move the pump? Thanks

[Powerstrokedogg]

3 the one your missing is probally the one under the high idle solenoid, i find it easier to remove the solenoid to get to it

[lincoln]

Thanks !!

[luckys420]

frdluvr, When you start it up first think in the morning do you get a black cloud of smoke? after its warm and in neutral, if you tap the fuel pedel do you get a puff of white smoke?

this is my situation I am curious to see if the timing helped you any.
thanks

[lincoln]

es sir ! And when pulling a horse trailer at night I could see a pretty good stream of smoke behind me in the headlight of trailing cars. I advanced the timing about 1/16 and it is a different truck. Very little smoke unless hard acceleration,and starts better.

[luckys420]

just bumped my timing a pencil lead width to the left. havent been able to get the milage yet, but it sure started easier, and was much, much quieter. also no white smoke out the exhaust.
without this forum I would have never even known!

[sbbamafan]

Have you had a chance to check it yet? I may have similar problem.

[luckys420]

pulled my trailer 60 miles today. after topping up to wheer the fule was visible. usually the tank would read 3/4 full after a trip this long. now the needle is touching the bottom of the full mark. didnt fill up to calculate but it is significant