afc housing and smoek screw

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Jan 8, 2008 | 01:28 PM

97dodgeram2500

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From: VA

afc housing and smoek screw

can anyone tell me how to locate the afc housing and smoke screw. ive looked when i had very little free time and cant find em. i probally looked right over them. and if anyone had pictures that would awsome and hopefulyl help me find them easier.

Jan 8, 2008 | 02:50 PM

Lil Dog

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From: Red Deer, Alberta Canada

Couple places to look...

http://www.cumminsdatabase.com/read.php?id=182

http://www.dodgeram.org/tech/dsl/mor...ower_p7100.htm

Those might help you out a bit..

Mar 13, 2008 | 06:12 PM

capt.Ron

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From: Texas (DFW area)

Quote:

Originally Posted by Lil Dog

Couple places to look...

http://www.cumminsdatabase.com/read.php?id=182

http://www.dodgeram.org/tech/dsl/mor...ower_p7100.htm

Those might help you out a bit..

I read over those threads and couldn't find info as to the location of the smoke screw.
I read this and in the paragraph below it indicates that adding fuel and/or moving the start wheel could constitute adjusting the smoke screw

Quote:

We buy a truck and the previous owner moved the housing forward, cranked the starwheel fwd and didn't even know about the smoke screw...so it's in it's stock position. The thing smokes off the line like a freight train and bogs like crazy...then when 6 or 8 psi comes around, it surges with power and breaks all the tires loose....that darn turbo lag right? Now let's tune the afc.

Start by getting the access to the smoke screw...take the AFC off and remove the break off screw and smoke screw cover. Loosen the smoke screw lock nut and back out the screw several turns until it feels loose. Now screw it back in by hand until you can "JUST FEEL" the screw bottom out on the diaphram. Snug up the lock-nut a little and now set the AFC back to a middle position on the pump. Take out that hex plug on top of the AFC and bring the star wheel back from full forward about 3 full revolutions and put the plug back in. Now we have a starting point.

Now my housing nor my starwheel is full forward but my truck does often seem to have a lag then a belch of black smoke. Just wondering if I need to adjust the smoke screw, is it something else or what.
Oh I'm also wondering how to find that darn smoke screw.

Mar 13, 2008 | 10:44 PM

Lil Dog

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From: Red Deer, Alberta Canada

Smoke screw, or rather zero boost screw. Looking at the AFC from the drivers fender, its located directly on the back towards the firewall under a small tin cover. It looks like a small bump on the end of the diaphram housing.

When you just slide the housing forward, you back out this screw to reduce the off the line fueling.

Mar 13, 2008 | 11:04 PM

capt.Ron

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From: Texas (DFW area)

Quote:

Originally Posted by Lil Dog

Is this not the same thing as the throttle stop or do I have the 2 confused?

Mar 14, 2008 | 12:10 AM

Lil Dog

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From: Red Deer, Alberta Canada

No not the throttle stop. Higher than that. If you look at the pictures at the database, there is one called aneroid I believe. You get a cutaway of the diaphram and the AFC spring etc. Well under a small cutaway cap on the right side of the picture you get the zero boost screw...under the "indiana" sign. The pump there shows larger parts but its the same on our pumps.

Mar 14, 2008 | 03:34 PM

Tate

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From: Airdrie, Alberta

The smoke screw is basically a fine adjustment to the position of the AFC Housing. Instead of moving the housing forward, run the screw in the smoke screw, and the AFC foot will move forward. This also will increase the preload on the AFC spring, so you may want to loosen it off a bit to compensate.