All, this is my first post on this forum, but i'm hoping for some ideas on my issue. My pickup (2001 Silverado w/4.3L V6) was leaking coolant slowly on the outside of the engine. Nothing too major, but I decided to take the lower intake off and replace the gasket. There was never any oil/coolant mixing and no issues with oil pressure before the job. I went with a good quality Felpro gasket with the metal reinforcement. I took my time and was pretty methodical about the entire process. I got everything put back to together and fired up the engine and noticed after 15 seconds or so, that there was no oil pressure, so I shut the engine off. One of the initial steps i'd taken was to drain the oil from the pan and remove the filter. Once everything had been completed, I put the drain plug back on, filled a new filter with new oil half full, then added the remainder of the oil to the crankcase. After turning the engine off, I spun the oil filter back off to see if the pump had filled it up. No, the filter was still half full. While the intake was off, I was very careful about keeping junk and debris from falling into the engine by tucking clean t-shirts across the top, and stuffing each port with rags while I cleaned the mating surfaces for the gasket. I can't imagine anything fell down inside because i was stupidly paranoid about that happening. When i put the distributor back into place, it seemed to drop in normally and the bracket bolt is flush with the top of the intake. So, i'm fairly confident that the distributor shaft engaged that oil pump tooth (or whatever you call it). I pulled the distributor back out and stuck a scope down there and everything looks ok, but I did notice that the oil pump tooth had some wiggle to it. I'm wondering if the distributor pushed it to the side when it dropped down inside the engine. Does that sound plausible? Is it possible that the pump somehow lost it's prime? It sat for 3 weeks or so with an empty oil pan. Any other suggestions that I should try? I appreciate the time and help of anyone willing to respond. Thanks!
Seth

 

I can't remember the last time I pulled a distributor on a chevy, so I can't remember if the shaft is splined or slotted. I do remember there is a plastic coupling coupling that both set into. I'd suggest, remove the distributor, inspect the pump shaft with a flashlight, and with a long screwdriver align the pump shaft to match the distributor, if slotted. I'm thinking the distributor won't seat (set flat) if the shaft isn't aligned.

 

You are right, kevinkpk. The distributor is slotted not splined. Not on pre-2001 5.7 liter and other engines they are not.

 

You are correct, the distributor won’t sit properly without the distributor shaft engaging the oil pump shaft. When I initially reinstalled it, it was all the way down allowing the mounting bracket to sit flush with the mounting surface on the intake. It couldn’t go any further down. However there was still no oil pressure. I took a couple of photos and a video with my scope camera that I’ll upload when I get home so you can see the play in the oil pump shaft. When I scoped it, there were no nylon piece(s) visible.

 

What I would do, find a screwdriver that will reach the oil pump shaft (cheapo) cut the handle off it, chuck it into a drill. Slowly turn the pump , see if it will build any oil pressure.

 

Yeah that’s a good idea. Do you know if the oil pump shaft is visible with the pan removed? I didn’t really want to do that, but....

 

The oil pan? No. Reach it from the top. The pump is bolted to the block, there should be no reason to pull the pan unless the pump is bad.

 

Here are the pictures that i'd mentioned. I couldn't get the video to upload properly. I don't see the nylon part that was described.

 

I ended up buying an oil pump priming tool off Amazon. It’s basically a distributor shaft without the gears that attaches to a drill. I ran it on the drill for several minutes, spun the oil filter back off and it was filled with oil. Put the distributor back in, and it runs like a champ again, normal pressure. I guess the pump just lost its prime with the oil pan being empty for a few weeks. Anyway, thanks again for the help!

 

Good job and thanks for updating your repair - I had no idea such a tool was available.