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Smoke screw ?

52283 Views 23 Replies 16 Participants Last post by  randemelissa
I have a p7100 pump on my 12v. I have the fuel turned up a little on it and have a boost eblow. Now I just want black smoke?

My ? is (not sure what its called) but it tells the IP when there is boost and the injection pump with then give the engine the fuel it wants. When you take the 4 screws off the get to that nylon washer do you losen of tighen that bolt to trick the IP into thinking it has boost?

I know that it is a pretty dumb ? but U just not sure.
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Moved thread to 94-98 Powertrain section...

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Moved thread to 94-98 Powertrain section...

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This is another dumb ? How do you do that?

Its a 95 12v with a boost elbow 33psi and a fuel plate.
This is another dumb ? How do you do that?

Its a 95 12v with a boost elbow 33psi and a fuel plate.


Go to User CP in the left corner and edit signature from there :thumbsup
Go to User CP in the left corner and edit signature from there :thumbsup
Thanks. got it filled out.
3
your (not sure what its called) is and AFC. And no, removing those four screws gets you into the diapham and the washers. That nut just holds them in place and doesn't adjust anything.

The "smoke" screw (I prefer to call it the pre-boost screw) is under the little cover held on by two screws on the back of the part you took off. You loosen the jamb nut and adjust the screw in or out with an allen wrench. Tighten the jamb nut and reinstal the cover.

The screw doesn't exactly make the AFC think it has boost, but rather sets the "zero" position for the AFC arm. Tightening it also increases the pre-load on the starwheel, so take that into consideration when adjustng.



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Thankyou for your help. Is it hard to adjust. How do you adjust it. If you don't adjust it right what can happen?
Its easy to adjust and there really is no wrong way to do it. You just set it to the pre-boost smoke level you want. If you want more smoke, turn the screw in. If you want less turn the screw out.
correct me if im mistaken but turning the screw up with the AFC gutted will not increase smoke correct?
So the only things that I need are a wrench and an allen wrench?
So the only things that I need are a wrench and an allen wrench?
You need to get the tamper proof cover off first.:rof Easiest way is to take the AFC off of the pump and then remove the cover. It has a tamper proof screw on it.
When the cover is off, all you need is a 10mm wrech and a 3mm allen key to adjust.
correct me if im mistaken but turning the screw up with the AFC gutted will not increase smoke correct?
Correct




I hate the ten character rule :hateit:
You need to get the tamper proof cover off first.:rof Easiest way is to take the AFC off of the pump and then remove the cover. It has a tamper proof screw on it.
When the cover is off, all you need is a 10mm wrech and a 3mm allen key to adjust.
ok where is the smoke screw located on a 97 cummins pump
ok where is the smoke screw located on a 97 cummins pump
It's in the same place on all 12 valves.
Read the directions above.
whats the easiest way to get the tamperproof screw off?
some people have pretty good luck with cutting a slot into it and making it a slotted screw... me, i just smacked it with a hammer and chisel then once the chisel was kinda embedded in it twist it out and replace it with a normal screw... i would suggest the first one :hehe:
the one on the afc housing that holds it down to the pump is the worst once you get that off pull the afc and use a cutting wheel on a grinder and cut a slit that fits one of you bigger screwdrivers and the others come out pretty easy, to get the first one off i put an extension on the drill and used the "grabit" tool
I know theres a link on here somewhere that says you can use a long drill bit (i forget what size) and drill out the center of the breakoff screw a little bit. Then you can hammer a torq bit driver into it and just unscrew it out. Thats what i did on my pump and it works pretty good and its easy. :thumbsup:
i used 2 hacksaw blades side by side to make a wide slot, then used my impact screwdriver (you hit the end of it with a hammer and it gives a twisting motion at the same time to loosen it and prevent it from stripping the slot out), and i re used them and have had no issues.
I want my truck to smoke less LOL.
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