Impact driver to get those easy to strip the head out screws.

Funny you should mention that I just used an old aircraft mechanic trick from 20 years in the trade and was tapping the screwdriver with a hammer while turning it and it it got him loose

Looks like rust on top of my fuel pin and my diaphragm looks like it's freaking stuck in there but I drive this thing all the time I can't imagine why there'd be dry rust on top of the fuel pin unless

https://cimg7.ibsrv.net/gimg/www.die...148f0b0edb.jpg
here's what it looks like

Stock fuel pin and it looks nasty but then also I thought these Springs were either supposed to be red or blue this one's red and blue

I took apart 2 pumps. Both had silver springs. One was a virgin Bosch remanufactured.the other had a fuel pin almost ground in half.

I bought a hammer driven impact driver. Put the bit in a 1/2" drive gun. Presto!

I took apart 2 pumps. Both had silver springs. One was a virgin Bosch remanufactured.the other had a fuel pin almost ground in half.

I bought a hammer driven impact driver. Put the bit in a 1/2" drive gun. Presto!

Spring had no pressure on it whatsoever so I marked the star wheel and the side of the inside of the bowl and backed the star wheel out 2 full turns. I cleaned up the fuel pin and will throw it back together and hop down the road and see what it does

Sadly I just discovered a small tear in the diaphragm. Couldn't see it before so I'm gonna have to try to find another one.
https://cimg8.ibsrv.net/gimg/www.die...e062b74561.jpg
I don't even know what symptoms this would display

Hey everyone, Ive gone and added the 366 spring, the THD fuel pin, and replaced all the seals in the top half of the AFC. Backed out the smoke screw all the way. Removed the nylon spacer. Adjusted the starwheel to with in 1/2 to 1 turn of losing lock from its keeper. Pre MY mods the pump when I got the truck was already advanced 1/8"(pushed up against the head). The smoke screw did have some pressure on the pin, the starwheel had 0 spring pressure, and the afc was leaking from the throttle shaft. With all that said, Pre mod I still had 19.2 to 20.28 mpg on average, and post mod im only getting 16 on average. I did install a tach, I try not to dog it. I shift between 1900 and 2100 on average, and I will usually shift into 5th around 40-45. I try to keep my cruising rpm between 1300 and 1820 ish depending on the gear. I have my idle set so that cold its at roughly 750 and warm its roughly 815-830. Im looking for any advice on how to get my mileage back or better than pre mod.

also, my driving is mostly 2 lane country road between 35 and 60 mph. sometimes up to 65 but rarely, and I try to cruise between 50-57, and even though I did remove the crimped keeper from the power screw, I marked the entire screw ahead of time and made note of the position of the fingers at the seam. When I reinstalled the scew post o ring replacement I used the marks, photos, and the removed keeper to measure and ensure that I am with in half a thread of the position it was at when I got the truck.

Im not sure if it would have a negative effect, but post mod I replaced the fuel filter..... this truck has 399k on it and I dont think that filter was ever changed. It was full of rust and what looked like sand. Like over flowing with it, yet I was still getting 19-20 mpg. put the new filter in it, and the whole engine runs smoother and quieter. Not sure if maybe the possible increase in available flow could be causing an issue. and yes I know this means I should drop my tank and clean it out, replace the float or sending unit ( im not sure if these trucks have a sending unit because we have the lift pump?), and or just replace the tank as a whole. Money and time are my biggest bottlenecks right now.

Shifting at 1900 is too earlier. The power band of a Cummins STARTS at 1800.
Does it smoke?
If so when? Low RPM, High RPM, Low boost, high boost?
When it smokes, it is wasting fuel and getting lower mpg.

when its cold it gets a faint white smoke, but when it warms up that goes away. If I accelerate gradually instead of just burying the pedal, it doesnt smoke at all, but if I bury it WOT it does smoke. I just dont get there in normal driving conditions. at WOT im usually at over 10 psi of boost.

When not towing or hauling, ie not needed all the power it offers, when would you reccomend I shift?

https://cimg4.ibsrv.net/gimg/www.die...7ea25aae1c.jpg
https://cimg5.ibsrv.net/gimg/www.die...e3071aee49.jpg

I try to shift so that when in the new higher gear I am close to 1800 when I get into it.