6.2 No oil pressure after pan removal/replace, help please

[neo]

Okay, I removed and re-installed the oil pan yesterday to put the girdle on, everything seemed to go great. Pan went on pretty easy, did not seem to have any hitches. Now, I can't get any oil pressure. Cranked and cranked with the IP disabled to prevent starting, guage did not budge. Then tried starting it twice, just for about 30 seconds of run time, still no pressure. Pulled filter (since I had changed it witht he new crank-case oil) and it is nto even full with the clean unused oil I charged it with prior to putting it on. Is there something I am missing? I drained the oil and put a bent welding rod up in the drain hole and it feels like the pick-up is there. Is there some way the pick-up could have ended up above the baffle, like bent or something? It is a 90-ish goodwrench replacement in an 89 burb. I really don't want to drop the pan again, but if that is what it takes. Anyone have any advice? Thank you very much in advance, and happy holidays!!

[murphyslaw]

i think ur gonna have to drop the pan again to check things out is sounds like the pick up got rotated up above the oil level. or it poped off the oil pump.

[neo]

Bummer. That is what I was afraid of. I was hoping it was something like it lost its prime. On my old rover v8, I have to pack the pump full of vasoline to get er to prime. Suppose I don't have to do this here? Do ya think I did any damage running it for a short bit w/o pressure? Should I pump some oil in somewhere to help prevent bearing damage? Thanks for the help!!

[neo]

Sorry to keep bumping this, but it is driving me completely crazy, so much so I can't sleep. I poked around through the drain plug and could swear I feel the pick-up at the bottom of the pan. I need a bore scope to see inside. But, WHEN I was trying to run/start to get pressure, I was a quart, maybe just a little more low on oil. Is it possible that the pump needed the complete pan full to get the oil high enough to pull a prime? I realize I am reaching but I am really reluctant to pull the pan unless I am very confident it is messed up when putting it back on. Also, is there some test I can make by pushing air either back down through one of the oil filter plugs into the pan, or pulling it up? Does the oil come from teh pump through the center hole in the filter or does it come ou through the outside and supply the bearings through the center? Is it possible to push oil into the galleys/bearings to help prevent any further damage? Can I pull out the vacuum pump (j-block) and run the pump with a drill or something? Or, am I completely screwed? I have to go to the inlaws for the next day and a half, so plenty of time to ponder, meanwhile we are borrowing a car from my parents to get to the inlaws. Yech. Thanks again for any and all help to my long winded ramblings.

[JeepSJ]

Try spinning the pump with a drill. Pull the vacuum pump and look down in the hole and you will see the pump drive shaft. IIRC it is a 5/16" hex. I used a socket on an extension (taped the socked on with duct tape - would suck to have the socket fall off) and spun the pump until I had pressure.

[arveetek]

Did you pull the oil pump or mess with it at all when installing the girdle? The oil pumps on these engines are self-priming. Once it's had oil, it'll always pump oil. Being a quart low or even lower wouldn't harm the pump. I've seen them pump when 5 quarts low.

Yes, you can remove the vacuum pump and drive the oil pump with an electric drill. With the vacuum pump removed, you won't get full oil pressure, as some of the oil will be allowed to drain back into the pan. The vacuum pump blocks off some of the oil passages forcing the oil into the rest of the engine. Still, you should be able to determine if it's pumping oil or not.

Are you sure your guage is working?

Casey

[neo]

Got it today. Read through the haynes manual over the last two days and found exactly as you described regarding the vacuum pump. Really made me feel better to hear it from you all. pulled the pump and ran the drill on it. after a few seconds it started pumping oil. It kept gurgling, and then simply pumped oil up through the vacuum pump bore. After the gurgling stopped, I drained almost all the oil to make certain the pick-up was at the bottom. Could not have had more than a quart or so. Continued to pump just fine. Replaced pump, filled her up with oil and violla! Good pressure again. I guess I did not let it run long enough or something. Thanks again for all the help!!

[arveetek]

Good to hear!

Casey

[britannic]

You did the right thing being cautious - doesn't take too long for a diesel to destroy it's internals with zero oil pressure! Glad all's well now... :)


Got it today. Read through the haynes manual over the last two days and found exactly as you described regarding the vacuum pump. Really made me feel better to hear it from you all. pulled the pump and ran the drill on it. after a few seconds it started pumping oil. It kept gurgling, and then simply pumped oil up through the vacuum pump bore. After the gurgling stopped, I drained almost all the oil to make certain the pick-up was at the bottom. Could not have had more than a quart or so. Continued to pump just fine. Replaced pump, filled her up with oil and violla! Good pressure again. I guess I did not let it run long enough or something. Thanks again for all the help!!