question- first run after lots of work

[jethro]

OK- started the motor up after being down for about 2+ months. It was running pretty smooth and quiet with just a hint of
exhaust haze. Here is what I have done to it in the last 2-3 months since it last ran.

installed new flywheel and clutch (not there before)
New 2-nd gen fuel piston fuel pump (no snubber yet) - replaced rubber diaphragm one
New oil seals front and back
new pan gasket
New 60 over valve springs
new manton chrome-molly push rods
A1 head studs
New cummins head gasket ( 1 re-torque after 2 weeks but before first run)
injectors overhauled with 6 new injector nozzles- all springs were tested to be OK ( 5 out of 6 nozzles were crusted over)
re-clocked, cleaned and painted the H1C turbo (not connected to intake yet)
Installed new exhaust manifold (the bus one which puts turbo down and to rear)

So tonight I bled the fuel system out till fuel came out at the injectors- put lines back on.
Kicked in the starter and it started hitting on one cyl - after about 45 sec it started catching on more and then wen to
idle. I noticed right away that it was running kind of rough- kind of shaking on the engine stand. I let it run about 3 or 4 minutes total in about 3 starts. Oil pressure came up within about 5 sec of first catching- so that looked OK.
It LOOKS like there is something different going on in the cylinders- either differences in fuel or compression. (the shake)
All the valves seemed very nice and free when the head was off. I set the valve lash to .010 and .020 per book and came back another day and checked them all again.
I would think there would be a BIG change in the fuel situation going from crap injectors to brand new nozzles-
Do new nozzles take a little time to "break-in" - ????????
I am hoping they didn't accidently get a bigger nozzle mixed in with the stick ones !!!!!!!

I didn't want to run it too long before I asked for help- in case there is something really basic I am missing !!!!!
I have not installed a fuel pressure snubber just after the new 2-nd gen piston pump. Would that cause a shake ?

Also it seems like the mechanical sounds the engine makes are a little louder now (tighter valve springs?)

I only ran it about 2 -3 minutes or so- definitely not time to even come close to normal temp.

Not expecting any head gasket leaks-
running water system unpressurised- didn't see any bubbles. No fuel or oil leaks.

Should I just run it some more ?????? get it up to temp and see if anything changes ?

I will wait for feedback before I run again - don't want to mess up anything now !

Thanks- Tim

[fatty]

I'd bet it still had air in the fuel system.

[jethro]

could there still be air bubbles after 2 - 3 minutes of running ? little bubbles would certainly make it run funny - I would have thought that the air would be gone by then though- but then Im just a beginner at diesel though ! hope it is as simple as that !

I am going to check the valve lash in the mean time just to make sure everything is OK there.

Tim

[jethro]

OK !
Just tried it again- (started instantly- about 1 revolution)
ran jumpy for about 20 sec and then it smoothed out quite a bit. I ran it for about 10 minutes more till it got warmer
and it seemed to smooth out the rest of the way. (must have been air bubbles) I still have what seems like slightly louder mechanical noises from the
engine internals- I have heard that they are not an especially quiet engine - is that correct ? but seems a little louder than before- maybe getting more (normal) fuel because of new nozzles ?

Tim

[Remps]

I think it was probably working air out of the injectors. Whenever I've changed injectors it would always run a bit rough for 30 seconds or a minute.

[PToombs]

It will be loud, it's on the floor on a stand! The truck deflects and absorbs a lot of noise, I've noticed the same engine in a payloader is louder than the one in a truck, it's mounted higher and the doors open right on the side of it. That being said, the piston LP is going to be make more ticking noise than a stock one, and if the insulation isn't on the tappet cover you will get tons of noise from there.
Glad you got it going!

[jethro]

I ran it some more tonight. once it got warmer (thermo still not open yet) it smoothed out some more yet.
It has a little pressure coming out of the crankcase vent- but that slowly improved before when I first got the
engine on the stand and started running it. Hope it will do so again.
(do we know ho much its supposed to have to be called normal?)

Only problem I can see anywhere is I have a very slight seep coming out of the injection pump. Its coming out somewhere on the engine block side- getting about 1 drop about every 10 to 15 seconds. It seems to be coming out about midway front to back- have to get my inspection mirror in there and get a closer look. Appears to be several inches forward of injection line
nuts. Hope its not a seal in the pump going........

Tim

[PToombs]

If it's in the middle it's the o-ring on the cover on the back side of the KSB. If it's towards the lines more it may be the o-ring on the pressure head.
Hope it's the one on the cover, the other one is way harder to change.