dan123dbl

I've read the step by step directions, watched a few videos, and over all the process seemed very straight forward.

I started by putting the engine at TDC with the timing pin.

Removed the 12mm bolt at the back of the pump, inserted my adapter and my dial indicator. I pushed the dial in all the way, and then backed it out half way and tightened the set screw.

Began turning the engine over backwards (clockwise with the barring tool) and the dial indicator didn't move until the dampner moved about 1/3 of the way around, but it moved and I stopped rotating when the gauge stopped.

I set the gauge to 0, and turned the engine over normal direction (counter clockwise with the barring tool) back to TDC verified with the timing pin.

I was watching the gauge the whole time and it didn't move at all. I believe I've followed every step correctly and I can't figure out why I can't set my timing properly ..

I just wasted a good 3 hours repeating the same steps hoping for different results

jimbo486

All of the steps follow the service manual instructions.

Could the set screw that locks the dial's plunger tube have come loose and sprung back out?

dan123dbl

I thought that too, but I checked and re-set the gauge about 5 times at TDC each a different time after trying to find the plunger lift. - going from tdc rotating until the gauge stops, setting to 0, then going back to TDC.

I have my injection lines still attached and I'm using the longest adapter, so I guess I should try using the short adapter with all the lines off since I don't know of any other thing that could be causing an unreliable reading on the gauge..

jimbo486

I can't recall if I removed the high pressure lines or not from my pump when I timed it. I do recall using the short adapter so maybe I did remove the lines. It certainly gives you more room to work.

j_martin

If you have the dial indicator inserted so the rotation counter is at 2 or 3, then turn the crank a little bit and the needle doesn't move, either you have an extremely sticky dial indicator, or the timing gears are way off.

cougar

Try this, set the crank at TDC and set the dial indicator to read 1.25mm. That is the stock timing setting. Now turn the crank opposite of normal rotation. The dial indicator should bottom out at zero and then rise again as you continue to rotate. If you go below zero, the timing has been changed. Rotate the crank in normal rotation until you find the lowest reading on the dial indicator again and set to zero if necessary. Now continue to rotate to TCD. Set your lift (timing) to what you want and tighten down the pump. Kind of a backward approach, but it works. This is something I figured out years back:

Cummins engine VE pump timing: (verified)
1.25mm pump lift = 12.5° stock intercooled (1.4mm stock non intercooled)
2.4mm additional pump lift (advance) = 21° - 22°
M&H timing spacer increases to 6.4mm advance = 31° - 32°

1mm pump rotation = 1° timing (verified)
1 tooth on drive gear = 10° timing (verified)

1/8" bump is 4° - 5°

hope it helps

j_martin

The point is, the timing is set 1.25 mm up the slope of the cam. If when backing the crank up, it doesn't immediately go down, then it was on the low spot on the cam to start with. It sounds like the OP was backing it up till it started climbing the back side of the cam for #4. I think the timing gears are out of step.

If the engine runs, it's timed way late. If the OP turns the crank forward till it reads 1.25 mm more, he can then discern if he can move the pump far enough to compensate, else he has to take the cover off and re-clock the gears.

We could be looking at a missing key in the pump shaft to gear connection also.

dan123dbl

Turns out the set screw to hold the dial gauge in place was pushing on the gauge just enough to bind up the part that needs to move. It would move when the piston is pushing against it, but it wouldn't go in with it.

All I had to do was tighten the set screw very lightly, and it worked great.

Timing is now set to 1.25mm lift.

dan123dbl

So you were right jmartin. Very sticky gauge when the set screw is tightened.

Thanks everyone for the quick responses and suggestions, I appreciate it.

thrashingcows

Now I have another reason to meet up with you.....I'd like to verify my pump timing settings as well, since your now an expert.......

Glad you got sorted out.....hope you figure out what's going on and why you have no grunt and poor mpg's.

dan123dbl

Sounds like a plan!

Now that i've repeated the steps a dozen times I should be pretty fast at it

I'll run this tank through and see if I have any improvements. I took it for a quick test drive and it seems to have some low end power back.

jimbo486

With larger injectors and depending on the type of nozzle, you may consider upping your static timing to 1.4mm of plunger travel at TDC. Considering if you have some haze at an idle.

dan123dbl

Ive read 1/8th inch bump is equivalent to 1.4mm lift. I wanted to have a real baseline for stock timing and I'll bump it an 1/8th once I've driven it over a tank and compare

Do you think 7x10s are large enough to delay the injection event and retard the timing?

jimbo486

Not really enough of a delay in the injection event to retard the timing. I think the pop pressures being too high could play more of a role in delaying the injection and retarding the timing than injector size but that would probably be a negligible amount. I'm just speaking to the fact that they're larger injectors and that if you had any haze at idle, a small timing bump just might clean it up.

What type of nozzles do they have, SAC or VCOs? And what spray angle? For your engine, they should be 145*.

dan123dbl

They are sac and 145*. The pop pressures are a bit higher too bit I forget the number.