Consise clear instructions on fuel adjust

[dmetalmiki]

I have spent hours with the .M.s which are simply vague in the extreme just pictures and hints absalutely no instructions.
I find the same in help forums.
How to turn DOWN the fuel on the 5 ton LDS 465 engine.
A big headache later and all and every answer is for turn up the fuel, On a deuce!.
Many answers (NOT one I would ever give!) are somehat like this.
a)"the adjustment is on the pump (yes!)
b)Undo the first nut DO NOT TURN THE SCREW or the ? will snap) (err ok!)
c)Undo the second nut and TURN??? the SCEW? one or two flats!!??? (Thought you said DO NOT TURN THE SCREW!)
And...WHICH WAY???? in out up down..this type of advice drives me nuts and just gives me a headache.
d)Then there is the picture of 'how to' Hmm, OK..JUST a picture nothing else! Great!
I will, or someone with understandable concise grammar will, (hopefully) step in and answer these questions without innuendo or 'guesswork'. or pictures with NO information on.
How to adjust the injection pump fuel down OR up. On the code 'B' (C,D,E,)and 'F'? fuel pumps. on the L.D.S series engines.
(yes the deuces may be the same procedure.)
A) Free the first lock nut?
B) DO NOT allow the screw to turn?. So, HOW do you PREVENT it from turning?
C) Turn the Inner nut (Which way to lean = less smoke. or which way to richen the mixture? = more smoke.
I am Guessing the second nut (NOT the screw?) moves in or out to change the rate. NOT the mixture as that screw contacts the levers linked to the governor mechanism? But, Then what is securing the SCREW or enabling it to 'Move in or Out?. I am guessing again that the Governor mechanism is pushing? that screw out, OR, or pulling that screw in?..and the NUT lets it 'Go In' when Undone or or Pulls it out when tightened.

Logic tells me that the inner Nut could be 'Affixed' to that screw which when turned creates the 'adjustment, in Weak = no smoke or out rich = smoke. And the first nut is a lock nut only.?
Obviously the first nut can't be affixed to the screw as it would not allow adjustment.

BUT, By way of 'common sense' (and looking at the schematic) both nuts can be undone, and the adjustment is by way of that SCREW being turned in or out to create adjustment by way of the 'movable plate' inside. As advised NOT to do! and thus NOT allowing the SCREW to turn and break or loose the 'linkage' going to the servo piston.

Interpretation, factual concise instruction, and or advices and corrections where necessary greatly appreciated.
And I am sorry for "Imposing" headaches! on anyone ploughing through all this to apply the 'fix'. But at least it will make perfectly clear how to carry out the adjustment, with the correct do's and dont's to ALL UN-sundry, old, young, experienced, inexperienced, or, just plain curious!.

Ref. TM-2910-226-34. Page Para. 1-30. Fig. 10-28 and 1-29.

 

[M543A2]

Five tons and deuces are the same. adjustment is in front of and below the fuel compensator and may have a seal or cap on it. remove this if applicable. grind down an open end wrench to a little less than the thickness of one of the nuts. this allows you to HOLD the back nut while loosening the front nut (lock nut) DO NOT allow the screw to turn (use pliers and a piece of cardboard etc if you have to, I never have). after backing off the front nut proceed to adjust fuel as follows. with engine warm and running, adjust one full turn at a time TIGHTEN back nut for MORE fuel, LOOSEN for LESS. after each turn manually pull accelerator linkage at pump to full stop and observe smoke. Then lock nuts back together when satisfied. we have run all of our 4+ trucks with the pumps set at FULL fuel (stop when you just feel the screw bottom out in the housing) even when pulling 56,000 lbs with a deuce at 60+ mph up hill and down for several years just the same way my step dad did for his whole tour in 'Nam grossing 80,000 lbs hauling jet fuel with NO engine damage on a 5 ton. There are some older deuce engines out there with early style head gaskets that you cannot turn up much and never an engine that does not have "TD" (thick deck) cast into it near the I.D. tag How I get away with it is to cut the pipe short enough that I can observe if there is fire in the exhaust, install A boost gauge, connect a vernier style adjustable throttle cable to the shutoff with a piece of chain so the normal shutoff over-rides it. pulling out the shutoff incrementally does the SAME THING as cutting down the fuel at the the fuel screw!I then set the shut-off control so that on the floor the deuce will only pull 15lb boost if i am pulling a heavy trailer to keep the governor from over heating things. I do not let it pull for more than 15seconds at full fuel (30psi) with cool down periods of a couple of minutes I have power timed all of these engines and set their redlines at 3100 to allow for full fuel when I shift at 2800 rpm following the advice of super stock tractor pullers who can make power and not blow engines.. Turning up a late deuce or a "TD" 5 ton DOES NOT blow them up the loose nut behind the wheel does by not understanding that temperature does not destroy engines HEAT does and that is all a matter of how long/ how far you hold down on the fuel! Tractor pullers have demonstrated that these engines can make around way over 600 hp hp for SHORT periods with cool downs. if they don't smoke they don't start right at all. They are dirty engines by nature and even say on the engine tag "exempt from ALL federal emissions regulations due to reason of national defense" show anyone this if they give you flak about smoke! It is YOUR truck and I want YOU to do what you want to make YOU happy! for myself I would only turn down a five ton if it made over 20 psi boost max and someone else was driving it or I was going to sell it. hope this helps. I have learned to say about some of these things "I have witnesses and experience and you can believe me or not , I won't get offended, but I don't care either, and I am NOT going to get into arguments over things because I respect other's rights to an opinion. I am NOT attempting to tell them how to use their trucks. if you are in the least uncomfortable with any of this DON'T do it.

 

[jbayer]

spelling

I'll try to help. I don't have a five ton, but do have 2.5, and have adjusted the fuel. Same procedure though.
so, first, here's a picture.
Down is just opposite of up.

1. cut safety wire if there.
2. Hold the nut closest to the cover with a thin wrench.
3. loosen outer nut.
4. Mark the inner nut for reference, like with a sharpie marker.
5. turn the inner nut counter-clockwise to turn fuel down. (less threads exposed=less fuel, more threads exposed=more fuel)
Factory would be about .15" of threads exposed .
6. So counter-clockwise 2-3 flats on inner nut, hold inner nut with a wrench, and tighten outer jam nut.
Don't let the threaded part turn. This would most likely only happen if the inner nut was frozen to the threaded shaft.
**If no nuts on outside (No FDC)then you open the little cover do the same procedure inside.(see pic)
Repeat until desired fueling level is reached.

 

[Floridianson]

It's not a screw but more of a stud attached to a guide plate. Most of the time the OP breaks off the stud because the wrench was in contact with both nuts and they twisted it off. As said above just make sure the two wrenches are very thin and hold the inner nut from turning when turning the outer jam nut. You can leave the jam nut loose till you find the adjustment you want then tighten the jam when the tune up is done. It's not made of glass so don't panic.

 

[dmetalmiki]

Thank you the three of you. Combined, all the information with the pictures IS >understandable concise grammar without innuendo or 'guesswork'. or pictures with NO information on.<
This combined post should be a sticky so that Anyone especially 'Newbies' can visit, read, inwardly digest, and apply.
On the subject of 'Inwardly Digest' You three members may (Ordered) "MARCH!" to 'The table'
and collect a..Cookie. And Thank you.
Other post'ees take note. Correct precise descriptive text (Easily Understood) with Excellent confirming pictures and explanations.

 

[Floridianson]

Glad you got it figured. As said the stud /wedge plate is spring loaded so you can leave the jam nut loose and take the truck for a tune up ride. Then when you find the amount of fuel you are comfortable with / EGT's then tighten up the jam nut and have fun. Also the pic that has no FDC the jam nut is the one to the rear of the IP and the forward nut will add or decrease the fuel.

 

[bennym45]

D.M said me to thank you, (All) as we are now good to go. To the shows. The fuel is not adjusted. (after I told "If it isn't broken don't fix it"). we will try it on the road first. After all what's a bit of smoke.