Cummins ISL Valve Adjustment & other power issues

[chiplamb]

Dan Hunt and I were discussing doing valve adjustments on our M380s last night. Procedure looks to be straightforward (from a justanswer page):

- remove the cap or oil fill tube on the front cover

- Rotate the crankshaft to align the top dead center marks on the gear cover and the fuel pump gear.

- With the engine in this position, lash can be set on the following rocker arms: 1I, 1E, 2I, 3E, 4I, and 5E

- intake valve is 12 thousands and exhaust is 22 thousands

- rotate the crankshaft 360 degrees and set lash for rocker arms 2E, 3I, 4E, 5I, 6I, and 6E

We were also discussing M380s with different amounts of power, perceived or otherwise. I know from discussing with him that I need to go over my hoses and clamps from the turbo as he's regularly seeing 25+ and I see about 21-24 max. I also wonder about IP timing - as he's never had an IP change and I've had a few changes during Don's ownership, if there's the slightest possibility that the pump timing might be off one tooth if there's any way to see this through the TDC hole or any other way to find this out?

[Randy Dupree]

I think the jake brake changes those instructions some (a lot).

[chiplamb]

OK and that leads to another question both Hunt and I have, on the low setting, the jake shudders at low speed. No issue on high.

Correct instructions would be helpful!

[Thumbqdm]

Our engine brake, on the low setting, also causes some "shutter" as the coach approaches a stop. I'm not aware of my controller being modified to change the downshift gear selection. So I guess I'm assuming this in normal operation! Or not?

[Dc2x4drvr]

My engine brake shudders on low.
My Boost gauge runs as high as 25 on occasion.
The manual says the valve adjustment is ok till 150k.
When my valves were adjusted they also replaced the injector o rings.

[Bruce]

Although the ISL in my Dynasty is newer ( 08) my boost is way higher. As high as 35. When it is only reaching 25 I know something is amiss.

[Dc2x4drvr]

Your engine is newer, different injection, so, 35 psi is normal. The isl400
with CAPS normal turbo pressure is 23-25 psi.