power adjustment screw

[DPKetchum]

Hey guy's whats the trick to getting to and making the power adjustment screw move. Tinkered with it 2 years ago and moved it half a turn. Now with new injectors I want to move it more!Never got all of the lock collar off and messed with it some today. It won't buge. Need to remove it etc and get rest of coller off but how in h--do you get to that point and how in the heck once out get it back in. Any tricks or suggestions?:{I guess i should also say that maybe it dosen't need moving,I installed new Bully Dog industrial injectors the other day and truck pulls hard now. Big differance then before. Idle speed actually went down some?pulls 20psi of boost max in a flash from hardly rolling to 80mph and top egt is 950. It dosen't smoke and to me pulls strong and smooth from off idle to 80. (unloaded)I know it can make more boost etc. What to do next??Thanks guy's.

 

[BushWakr - RIP]

DPKetchum,



The tamper cover on that screw should just pry off. It is a bit tough to get off sometimes, but it will give. It has a little spring clip inside that keeps hanging on making your life difficult.

When I got mine off the first thing I did was make a small punch mark on the small (6mm) end of the adjustment screw. I used a spring loaded center punch used in aircraft work. Whatever you use, just make a permanent mark for reference. ( Also make note of your RPM before you start this. It can also be used as a reference later. )

Then all you need to do is loosen the lock nut (13mm) and turn the screw in. On some pumps you may find that the lock nut can't be backed off more than a turn or so before it hits the tack welded tamper ring on the screw, which means you can only turn the screw IN one turn.

If you are determined to remove the lock collar then carefully loosen the locknut just enough to move the screw, back the screw out carefully and mark the position of the locknut before going any further.

That way you know roughly were to turn it back in to, when you reinstall it, without the lockcollar.

Is this making any sense???

BTW, the small hex end of the adjustment screw is a 6mm.

To remove the lock collar you will need to file or dremmel the tack weld on the thing.

Once that is off, position the locknut by using your reference mark, and screw the thing back in.

Snug the locknut, and start truck. Check idle RPM. If you were carefull when you marked the locknut position, and put it back right, and your RPM is the same... your good to go.

Often when the full fuel screw is adjusted inward past a certain point the idle will climb above pre-adjustment level.



One CTD'r told me he loosened off the locknut just enough that he could move the screw with his 6mm socket. Before moving anything he put some of that putty stuff you use to stick pictures/posters up on drywall, and wrapped that around the locknut/screw so it was "stuck" in place as he removed the screw.

I just counted how many turns the locknut backed out till it hit the lock collar, then reversed that process when finding my starting point prior to removal.



Ok, if you find that you adjust the fuel screw and your idle goes up you may need to adjust your low idle screw to bring it back down. Usually around 750-850 is good.



If your timing is set right (1. 45mm or 15*advance) you should tune the fuel to your personal preference.

Generally you want low/no smoke at idle, boost 25-27psi at WOT empty, and EGT's as low as you can get them, with 1250*F MAX

Remember when loaded and pulling hard you will see higher boost and higher EGT's so if you are hitting 1250*+ now, empty, you'll see more if you pull a hill loaded, and at WOT.



I'm sure I made this too complicated but I hope that it helps a bit.

If you have more questions, just ask...



Clear as mud, right...



Bob.

 

[DPKetchum]

OK,for sake of knowledge why did idle speed go down some with new injectors. Should I worry about using power adjustment screw or go into pump. If it makes 20psi easy unloaded should i be hunting for more?The differance injector swap did was. hardly beore would it pull maybe 19psi wot gutting it at end of pull high gear now it just zaps to 20 and hardly get 900 egt with 9600lbs behind it on incline,now it again mid speed up it's at 950. It pulls and rev's lots faster and it's smooth power. I was expecting more. Was I wrong in these thoughts. I did adjust high idle out 3 turns a few days before swap. It did'nt change much until injector swap and now it pulls boost and egt all the way to end of rpm's.

 

[BushWakr - RIP]

With your setup right now you have room to work with.

950*F EGT's is pretty good.

If you haven't set your AFC diaphram that is were I'd start.

Check out my pictures ( in "Bobs VE Gallery") you will see what the AFC diaphram/cone looks like.

Here's the link to follow. .



https://www.turbodieselregister.com/user_gallery/displayalbum.php?&albumid=453



Set it so it looks like the one in the picture, that is the deepest part of the cone should face to the front of the truck. That will allow for max fueling quickly. If you have smoke at start off or low boost smoke, adjust the smoke screw. It's labelled in the picture too.

Back it out till you're smoke reduces and tighten it up.

As you work with the pump pretty well all the affected parts are shown in that gallery of pics for reference.

Once you fine tune this adjustment you may want to tweak your governor a bit since you are running 4:10's.

bob.

 

[DPKetchum]

Ok i kinda understand what your saying and your pictures in the gallery are great. I have also ran a copy of Fritz's and Geno's garage pump adjusts. But i guess I'm a little cloudy on the tweek governor setting since I'm running 4:10 gear thing?