So, the previous owner of my new truck had the IP resealed relatively recently. When he got that done he got the mechanic to turn up the pump quite a bit. I don't think he did a very good job because it smokes quite a bit, mostly after shifting when under a load. I have tried quite hard to reduced this (more revs before shifting, backed smoke screw out) but it still hasn't helped. I think I am getting to much fuel before the turbo lights. I want to back out the starwheel but I am afraid that I will undo all the work that the guy paid to have done in resealing the pump. Am I gonna create trouble by trying to open the AFC?

If this is alright, any tips on cracking those flathead screws on on top of the AFC? They are really on there.

 

There is no risk of breaking a seal there is no fuel where the starwheel is. Get a big screwdriver and a hammer lol...

 

No worries as Bill said. I've had luck using a long, wide blade screwdriver. The long shaft somehow helps.

I've since replaced the 4 bolts with stainless socket-head cap screws. Far easier to remove the AFC top now.

 

Same here. Allen head bolts are WAY easier to work with.

Attachment 37305

 

Ok I just backed it out 1.5 turns (CCW right?) and I feel like it smokes even more now? Should I bring it all the way down or up and count from there? Where is a known setting good for daily driving? I feel like I messed it up even more haha

 

If you can see where the pin has been riding on the cone, then that's where the starwheel is at. The bottom of the mark is where the pin sits at at no boost.

If its' not at the bottom of the ramp, bring the starwheel up until you think you're about there. The threads on the starwheel are pretty fine, so just turning it a turn and a half isn't going to do a whole lot.

Either turn the cone to a different spot, or clean off your previous mark and rub some axle grease where the pin hit on it's previous run. Take it out for another drive, and see how far it's down then. There will be a point where the spring will bind up and not be able to let the cone down any farther, so if you're looking to minimize smoke but still keep you max power, you're preferred setting will be right before that point.

 

Wow ok thanks, I'll tinker with it tomorrow and try and find that point.

 

You can run the starwheel up as far as you can until just before the spring bind. Usually that would bring it to about flush with the top of the bushing it's threaded onto. It'll increase the spring tension on the fuel pin. Thus, requiring more manifold/boost pressure to push the fuel pin down and not fueling as hard until that specific manifold pressure is applied.

 

I haven't actually done this, but it just kind of hit me:

If your fuel pin is working correctly, and comes out into the AFC bore when you hit the throttle with the engine off, then I would think you could just do this like that.

Pull the AFC top and clean and grease/paint/mark your fuel cone. Adjust your starwheel up and put the cone back in, but don't put the top on. Hold the throttle wide open(engine off), and push down on the fuel cone until it bottoms out.

Rinse and repeat until a happy balance is found. The only 2 things I can think of going wrong here is if maybe working the pin like that with the engine off may be a bad thing(someone with more knowledge of the intricacies if the VE pump will have to confirm that) and remembering that the AFC cap pushes down on the cone a bit so you'll be getting a slight false reading on where the pin's lowest point will be.

There is some webbing in the top of the cap that can be ground out as well, to let the cone come up a bit higher. Every little bit helps.

 

As long as the fuel pin/cone is in place, the AFC pin, which is what rides against the profile of the fuel pin/cone, cannot fall out.

 

You guys just keep on talking; I am a'learnin' too.

Before reading this, I never really did quite understand the star-wheel business.

It is beginning to make sense to me now.

If I am understanding right, once the ideal star-wheel position is attained, that is where it should reside, regardless of which ramp/cone setting is desired, right ??


Also, what purpose does that little bolt under the tamper-cap serve as in regards to star-wheel setting ??




Also, as regarding "paint-marking" the fuel-cone thingie, would not a jar of machinists Prussian Blue lay-out fluid be just the trick ??



Thanks.

 

That screw under the tamper-cap is the infamous smoke screw. That sets the no-boost fuel delivery rate.

 

I really didn't feel like pulling the AFC open again tonight but I didn't want to say I got nothing done so I switched my throttle rod over to the inside hole, and wow, what a difference! I took her for a test drive and smoked even worse on the shift into third goin up the hill but man I was flying. Had a great time.

I will give the AFC another shot tomorrow before school. I am really aiming to maximize fuel efficiency right now, I just started college and emptied my savings acct into this truck (no regrets there) and I would really like to see 20+ mpg. I think it's very possible right now I just have to get this smoke problem sorted out.

 

If I am understanding this, that "smoke screw" pushes the cone down and keeps it from coming higher, thus permitting the fuel pin to act the same as if boost had pushed the cone down the same, right ??

 

Yes, it affects how much fuel is pumped pre boost.