still bendin wrenches on my 92 comp. is 309 on the high side 291 on the low side seems low to me but cant find spec not in my sevice man

 

That compression does sound low.. Cummins does blow by tests on these engines as opposed to an actual compression test, but high 400's for compression psi is a good number.

 

x2

The Cummins blowby orifice tool is simply a tee with one .221" (15/64-in) outlet. Connect one end of the tee to the end of the blowby tube. Put a manometer on last tee outlet. That is your blowby tool. They sell them at the Cummins, but you can make your own for around $10. A simple manometer can be made by looping into a 6 feet of clear tubing into a 'U' with water in it half way. Mark the water level start the truck and measure how high the water level rises with a tape measure, multiply it by 2, convert it to LPMs.

Rough conversion is 1"= 27 lpm, add 3 lpm for each one inch (1/2'' of rise in the tube) of water

Cummins new 5.9 engine numbers are:
63 liters per minute(2.5" water rise) @ 2200rpm,
76 L/Min (3.5" rise) @ 2500rpm
85 L/Min (4.5" rise) @ 2800rpm.

Worn engine that needs rebuilding are roughly double i.e.
126 L/Min(10.5"rise) @ 2200rpm
152 L/Min(14.5"rise) @ 2500rpm
170 L/Min(17"rise) @ 2800 rpm

 

Thanks RS I made one today pulled 2" of water so I dont think my motor is "shot" tried pump timing to no avail this one sure is kickin my butt