I did a compression test on my engine as follows:
1-450 psi, 2-200 or 0 psi, 3-460 psi, 4-460 psi,
5-480 psi, 6-445 psi,
I must have a hole in the piston on number 2 cylinder?
So can I drop the pan in the truck?

 

Or you have a tight valve hanging open, or the cylinder walls are scored. Did you add motor oil to the number 2 and try again?
The pan can come off in the truck but its a pain. Usually the trans has to come out, you need to sneak in after the pan is loosened and remove the pick up tube bolts, loosen the motor mounts and jack the engine as high as you can get it. Not a pleasant job, but can be done.

 

I well recheck the # 2 adjustment and add oil prior to the compression test.

 

I haven't pulled the pan on a Cummins,but I just got done pulling the pan and replacing the oil pump on my 86 Mercedes 300 SDL. It was surprisingly easy, I have to give it to the Germans, there is about 3 or 4 inches behind the engine to the fire wall. The big pain was the 44 bolts that held on the main and mini oil pan...Mark

 

From my post about rolling in a new thrust bearing . . .
FWIW, a lot of guys were complaining that they had to practically pull the engine out of the bay to get the pan off. I found that by raising the transmission slightly I could get the pan to slip down under the flywheel housing, slide back, and out.

To remove the engine pan in a 4 wheel drive chassis:

Remove the fan shroud, fan, & fanclutch. Drain the radiator. Disconnect the intake hose @ the turbo, the aftercooler hose elbow @ the turbo, the aftercooler hose at the intake horn (if so equipped), the exhaust pipe at the turbo, the exhaust hanger at the bellhousing, the upper radiator hose at the radiator, and the lower radiator hose at the engine. Remove the nuts on the engine mounts under the crossmember. Remove the nuts holding the transmission to it's mounting plate. Unless you have a significant suspension lift, raise the front of the truck by the frame until the front axle reaches full droop. Raise the engine by the front lifting eye until the engine mount studs clear the crossmember. Jack up the transmission about 3/4 of an inch, and slide the engine & transmission assembly forward about an inch. Raise the front of the engine another until there is about an inch between the bottom of the engine mount studs & the top of the crossmember (while paying attention to the bellhousing contacting the seam in the cab).

 

I think the only proper way and fastest is to pull the engine. You can cut the cross member and weld heavy flanges on it so it can be bolted back up but the structural integrity would be lost. I use to jack the motor up and take all the bolts out of the pan and slide my hands in there and remove the oil pick up tube. Let the tube fall into the pan and slide it all out. After thinking twice, if my hoist ever failed I would have lost my hands for sure.

I think it all comes down to tools, do you spend an hour or two and remove the bumper, grill, front end/radiator. Pull the motor out and work on it that way? Or do you spend time trying to get the pan right and hopefully the seal is sealed in such a cramped spot. I've spent all day trying to get that darn pickup tube in and I was able too but I would feel more comfortable if the motor was out.

Check the valve clearance as well.

 

I removed the valve cover on # 2 cylinder and found that the intake push rod was off the tappet adjusting nut
and holding the intake valve in the open position.
Removed the rocker and push rods tubes.
Added oil to the cylinder and took a compression test.
The results were 0 psi.
Could it be either a bent valve or hole in the piston or both??

 

The valves have to open and close in order to build compression.

 

Hi Bruce, I would put it all together, adjust the valves and then check it.You may have gotten lucky...Mark

 

I felt the same. I pulled the motor on my Black crew cab last winter rather than fix a leaking oil pan in the truck. Gives me a chance the work safely and easily rather than cramped and risking my hands working under a 12v hanging on and engine hoist or some other rigged up set up.
The VE pump was re-sealed, rear main seal, tappet cover gasket and a new LPLP installed as well as I had great access and the parts on hand. It was easy and much more fun work.

 

Angry Johnny was right about the valves working to get air in.
Maybe368 you were right about trying it because luck might me on my side.
Well I did what both of you said and cranked it over getting 300 psi on the first few cranks
and then cranked it about 10 times and it went up to 450 psi
The engine runs smooth with my limited hearing at 725 rpm ,but I( still smoke less then before.
Do I retard or advance ?

 

What a coincidence! My cousin Andy and I pulled an OM617 from a rotted out 1983 300D last weekend to swap in to his 1986 Jeep Comanche. Had to remove the entire pan assembly so that a shop in Newville PA can remove the steel pan mounting area and weld in a new aluminum sump to clear the axle and steering linkage. It was a PITA upside down on an engine stand. Most of the bolts were easy pickins but a few were just tough to get to. I can't imagine doing that in the car would be fun. BTW: I pulled some parts off the car if you need any (headlights, grill, tail lights, under hood stuff.)

 

Is that the 5 cylinder? I may need some of those parts,I'll let you know when I get back there,currently in Mexico. the OM603 (I think) wasn't that bad, it was just 108 plus when I was doing it that was a real pita. It had blown a turbo (unobtanium) and it turned out that it sucked a woodruff key into the oil pump, that then knocked off a chunk of the oil pump, that was then sucked into the pickup and was acting like a flapper valve. Something had torn the filter screen out of the pickup. When I put an oil pressure gauge into the sender port I was getting between 3 and 40 psi, fluctuating between the two. I got a used oil pump off of Ebay and it is putting out 75 psi when cold and 65 psi when warmed up (with it throttled up).The car has 345000 miles on the clock, original motor and doesn't seem to be damaged by the carnage. The president may be mad at Mercedes, but they can sure build tough diesel engines. My buddy here puts the OM617 into old 4Runners. He has done 3 of them and they sell pretty quick...Mark edit: It is unbelievable that the engine survived that, the remaned turbo was 700 dollars, the replacement oil pump 70 bucks, not too bad...

 

Never tried one on a Cummins but you should look into doing a leak down test. It can tell you a lot about your engine and help you find where you're losing compression. I'm not sure what adapters you would need for the injector holes though. I did one on my /6 engine and found the misfire that had eluded me. #3 exhaust valve is leaking. I could hear it hissing through the tail pipe. The tester I have screws into the spark plug hole and uses shop air to pressurize the cylinder to 100psi.

 

Yeah Mark that's the 5 cylinder diesel. Pretty stout looking engine. About a year ago Andy and I pulled one from an '85 300D in a local U-pull-it (Stoneroads in Shamokin PA). I knew the car had been there for several years but I never got around to getting the engine out of it. I had business up that way and had some time to kill so I went to the JY about an hour before they closed. I saw that the car had been moved from the yard to the area where they prep stuff for the crusher and the engine was still in it. I talked to the guy running the place and he said he'd put off crushing it for a couple weeks so I could come get the engine. Said he hated dealing with those particular cars because the fuel tanks are a bugger to remove. 2 weeks later we went up and pulled the engine. The guy that ran the place was really helpful with the loader too. He charged me $150 for the engine, accessories and some Dodge truck parts out the door. Figured I couldn't beat that! Got the engine home, built a stand for it out of scrap metal, hooked up a couple batteries, fuel lines, looped the coolant lines and she fired up after somewhat of a fight. No too bad for an engine that had been sitting at least 3 years in the JY. Sounded OK. Needs tuned up but no horrible noises or bad smoke. 185K on the car odometer. I don't have a use for it yet but at least I saved it from the crusher!