No oil pressure on my 340 :-(

[Rdchallenger]

I feel like I've been kicked in the gut. So close and now that light at the end is disappearing.

Primed oil pump with drill until it came out of the sending unit hole, did engine break in, changed oil, no knocking or pinging etc.

Oil pressure is now showing 0 psi, thought maybe the aftermarket sending unit or gauge went bad but they checked out,
Pulled the sending unit and cranked the engine all the way to start to see if oil would shoot out of sending unit hole but got nothing,
Pulled dist and there was oil on it,
Pulled valve cover and again cranked the engine to check if oil was getting to rockers and did not seem like it was.

What happened to my engine  .
Planning on pulling oil pan in the next day or two.

[anlauto]

I assume it had plenty of pressure during the engine break in ? Maybe you got a bad or wrong oil filter ?  Seems very odd you went from good pressure to zero after an oil change 

[B5fourspeed]

Remove the oil filter and see if there oil in it.Fill the oil filter 3/4 full then put it back on.Had the issue with my fresh 440.

[Dakota]

Disclaimer:   I'm no engine expert.   The stuff below is what I'd do if this happened to my 340 if the oil filter check mentioned above doesn't improve things.

If the engine is firing, that means the rotor in the distributor is turning which means the gear on the distributor is engaged with the cam shaft, which (in theory) means your oil pump would be turning too.

Long shots but easy to do: if you haven't already done so check to make sure your distributor is fully seated on the intake manifold, the distributor shaft is the right length, and that the gear on the distributor shaft isn't loose.

If you can eyeball the gear on the camshaft, see if the teeth are intact.

Only other  things I can think of are that something failed in your oil pump or your oil pump dropped down such that the distributor shaft is no longer engaged.  Either way it looks like your plan to drop the pan is the right thing to do. 

Good luck with it.

[Brads70]

Fram oil filter?

[Chryco Psycho]

Check the dist to make sure the drive tip is OK , it should be if it runs , then pull the oil pump drive , I have seen the tip break off , you might get it out of the pump with a good telescoping magnet if that is the issue .
I have also seen pumps that would not reprime after changing the oil so you could run a drill on it again to get the pump reprimed , could be that simple !
Don't use fram fiters  use WIX / Napa Gold

[Mr Cuda]

If the engine was assembled from a bare block, make sure the cam galley plug was installed.
I've seen machine shops miss installing it. You can check with distributor removed.

[jimynick]

There's a gallery plug that goes in the rear of the block vertically. Take out the oil pressure sensor and put a rod (old coat hanger) down it. I'm trying to remember the depth it should go and want to say somewhere in the 7" area. Maybe there's someond here who can give a better figure. If it didn't get re-installed the oil pressure will be virtually zilch.

[MoparLeo]

Follow Chryco's advice on this one.

[Rdchallenger]

Okay y'all here we go... changed oil filters and tried priming the engine to no success. At that point I pulled the oil pan and found metal chunks in the pan (see pics), dug a little further and found that the oil pump had failed where the driveshaft connects into it, and that the driveshaft looks to have been chewed up as was well.

You can also see where the oil pump itself cracked as well where the bolts go in. Here's the crazy part, the pump was not seized, took it apart and was able to move it freely.

So what would have caused this type of failure? Do the driveshafts come in different sizes and I had the incorrect one in? I'm not aware of any other sizes besides the standard Chrysler SB.

Definitely looking for solutions and brain storming possibly on this so that the same problem will not happen again. Feel free to throw some ideas at me please.

[Dakota]

Distributor shaft has too much runout?   

[MoparLeo]

I see a crack in the oil pump housing. I will go out on a limb and say the oil pump was loose and wobbled allowing the shaft to crack the input portion of the pump.

[jimynick]

I'd suggest that the oil pump never seated properly and was cocked in the hole. That'd also explain why the mounting flange on the pump has a crack, as it attempted to seat by hauling on the flange by the bolt. That'll also help to explain why the one side of the drive socket is chewed out. 

[anlauto]

What a mess

[jimynick]

What a mess

Yep, and with the silver "paint" showing in the oil, this thing needs to come right apart and get flushed, or some of those metal particles will cause a nice, big failure given time. What a giant PITA!