[Brighty]

If you get them all within a 5 bar zone that is pretty good. The engine will run better the closer you match them. Since your injectors have been used the internal spring has relaxed some. Not uncommon. After you get them back to specs they won't change much. Those little shims come in 30 different thicknesses so you could spend hours getting them right on the 245 bar mark. Your #1 was dead on the mark. #2 was pretty bad off the mark. The other 2 were sort of in the middle.

Thanks mate. Im still stumped how the shim I put in would not allow it to pop/spray at all then when I disassembled and removed, reassembled back to the way they were originally and retested they were pretty much at spec. (??)

What about the pump timing and concerns with that given the markings on top of the pistons?

 

[Blackduck596]

No shims certianly makes it hard to set without a lot of messing around.
The 1.8 would most likely come up fine with 2.0 in it.
Char may have handle on the thinest sizes Cummins supply but Precision do not have thin shims.
Are you 100% sure there were no shims stuck in the bodies?

 

[Brighty]

No shims certianly makes it hard to set without a lot of messing around.
The 1.8 would most likely come up fine with 2.0 in it.
Char may have handle on the thinest sizes Cummins supply but Precision do not have thin shims.
Are you 100% sure there were no shims stuck in the bodies?

Thanks Steve. I'm sure there were no shims in those other 3 which I found quite odd given the other had a 1.8mm shim.
I'm tempted to pull them apart again.
Still got me stumped why it wouldn't pop/spray with one single shim added the same size as you used. Just didnt make sense.

The other thing.... should I be concerned with the 2.0mm timing on the pump given the spray pattern on top of the pistons at the start of the thread? Can't afford for this to go wrong anymore or risk damage.

 

[char1355]

The standard Bosch shims range in thickness from 1.00mm to 1.98mm. You'd never want to start by using the thickest. The sizes are 1.00, 1.04, 1.08, 1.11, 1.14, 1.18, 1.20, 1.24, 1.28, 1.30, 1.34, 1.38, 1.40, 1.44, 1.48, 1.50, 1.54, 1.58, 1.60, 1.64, 1.68, 1.70, 1.74, 1.78, 1.80, 1.84, 1.88, 1.90, 1.94, and 1.98. Cummins part numbers run from 3905156 thru 3905186. Always start with the thinnest and see what effect it has. It is very strange that you'd have 3 injectors with no shims at all. Even with brand new ones there are usually shims to fine tune them to proper specs. Prices for these little devils ranges all over the board. Average is around $10 each. The Cummins store sells them for $9.55. If you have an injector that won't pop at all there is something wrong there.

 

[Blackduck596]

All my injectors (12) had 2 shims. The .6 was used with one of the others to get the required stack as Precisions and Cummins shims have nothing under 1. Think the smallest stack I pulled apart was 2.0 The spring seat is easy to put in upside down and will jam the needle.

 

[Brighty]

Ok guys, rig is up and running.... finally, YAY!!
Have timed the pump at 2.0mm as per data plate BUT.... even with the new HX30 Super on seems to be running extremely lean. Tiny puff of smoke at take off but other than that... nothing, no smoke even with WOT for the short bursts I could around town. EGT don't go over 300 degree celcius(570f)
Checked power screw and from bottomed out, was turned out one turn and locked off.
Smoke screw is all the way out.
Star wheel was level with top, basically all the way out. I screwed in 3 turns and didn't see much change... maybe just a little more poke but not worth stating it made a difference.
Does not have the standard mechanical lift pump, different setup in the conversion I have so, .... it HAS an elec lift pump which I don't believe is delivering anything over about 2-3psi post filter before IP(it is a new filter). Shitty fuel pressure gauge I put in didn't even move before I started engine(should show some movement as is should be priming with engine not running). So in saying this, will be looking to replace with another elec lift pump. (What psi/volume elec pump should I be aiming for?) Budget cant do FASS, but was looking at a Carter or Holley

I don't have any tuners nearby(nearest reputable cummins one is about 5hrs away) to look at the truck so I'm trying to tune myself so I melt a piston of the like.
Was thinking of adjusting back to 1.8mm timing and see what difference this makes. Thoughts?

To go back over the truck setup....

• CPL 592 with VE pump
• Timed to mark 'B' in IP gear
• ARP head studs
• 60lb valve springs
• O' ringed head(new head)
• Stage 2 colt cam
• 3200rpm spring and fuel pin
• HX30 Super(brand new) running about 18psi
• Injectors are Bosch 6x.010"
• FMIC, 2.5" pipework
• Ported & port matched exhaust manifold to head.

 

[Blackduck596]

What fuel pin is in the pump?
No smoke and low boost does suggest lacking fuel.
Where is your EGT gauge plumbed in?

 

[Brighty]

What fuel pin is in the pump?
No smoke and low boost does suggest lacking fuel.
Where is your EGT gauge plumbed in?

Fuel pin as below photo(unknown source as previous owner installed)
EGT gauge is about 80mm post turbo in exhaust pipe.

 

[Blackduck596]

OK, close to full travel. How much of a mark on the straight section of the pin? looks like it could do with some lube in there as well.
With the EGT post turbo the readings will be a lot lower than pre turbo which is what most use.

 

[Brighty]

OK, close to full travel. How much of a mark on the straight section of the pin? looks like it could do with some lube in there as well.
With the EGT post turbo the readings will be a lot lower than pre turbo which is what most use.

Thanks mate. No marks on the flat part of the pin as there was 3 x copper washers in there which would have replaced the original plastic ones.... I've now removed those and getting full travel into the depth of the groove.
I've found some more issues.... gov spring in the IP does not look anything like a 3200 spring(glad I bought a new one just in case.) and the slide pin was stuck and not moving in/out. Im unsure if the the O ring in there is the correct size or if the top cap that gets held in by the allen key nut squashes it to much, putting too much pressure on it thus not allowing it to slide.
Hopefully the photos below can give a better idea of what's doing with the slide pin, but need to fix this and I think I should be right.

 

[Blackduck596]

Slide pin along with the fuel pin likes lube, I put a little oil into the fuel pin tube to lube both.
Stuck pin maybe all your problems.
Green O ring would suggest it is correct.
Cheers Steve