remove stuck oil pump drive gear LA 340 - SUCCESS!

[Dakota]

I tried to prime my oil system today, but never got past removing the drive gear under the distributor.  I've tried turning the gear clockwise with a screwdriver and can't get it to budge. I've put a wrench on the screwdriver to add a little leverage and that didn't work either.   I've tried rotating the crankshaft (clockwise) and then going back with the screwdriver and wrench - no good.  I've read some posts on other Mopar forums that talk about getting a hook of some kind under the gear but I'm having trouble understanding what that looks like.   Another option I read was to grab it from the center and outside edge with pliers and pull up - that looks like a great way to damage the gear and drop some pieces of metal into the oil pan.

I've primed the engine before so I'm not really sure what's changed.   

Suggestions?   Drop the oil pan?  Remove the intake manifold?   The gear is stuck and so am I.

[RJChallenger]

@Dakota . What happens if you try to rotate to drive gear counter clockwise?

[Dakota]

I tried going counter-clockwise with the screwdriver and the screwdriver/wrench.   Same result - very stuck.

[RJChallenger]

  I would think pulling the intake would give you better access to the gear. Dropping the oil pan would require removing the oil pump also. good luck

[Bullitt-]

I don't recall thinking mine was stuck but didn't see how to remove the gear.
I ended up inserting 2-flat blade screw drivers in the slot, kind of crossed them then pulled them together to wedge in the slot. I was then able to lift the gear with a twist.

[73_Cuda_4_Me]

The drive gear has to turn clockwise on the 340 to raise it up on camshaft gear... surprising that turning it with screwdriver and wrench wouldn't force the gear up with the screw force the gear interface would generate!

Is this a new rebuild that you are trying to prime? Is it the original oil pump and drive gear?

I'm wondering if the oil pump is locked up, not letting the drive gear turn while it raises up on camshaft gear?

Or maybe the hex shaft the drive gear has is twisted somehow where it goes into the oil pump?

[anlauto]

Yea, that's odd, I've never heard of them not coming up before

[jimynick]

I've seen where schmutz buildup on the shaft will make it hard for the shaft to lift through the bushing it runs in. As for a "hook" think more like a right angled piece of steel that's thin enough to get under the edge of the gear and yet strong enough for you to pull up on it. A chunk of say  3/4-1" wide 1/8" stock that you could bend and drill a hole for a slide hammer to connect to would probably be thick enough to give a couple of yanks on. Did you try holding reverse torque on the screwdriver slot while you rotate the engine on the starter? 

[Dakota]

Is this a new rebuild that you are trying to prime? Is it the original oil pump and drive gear?

The motor was rebuilt about 5 years ago but hasn't been run since.  The oil pump was new with the rebuild. I'm not sure about the gear shaft.  I've successfully run the oil pump with a hex shaft at least once or twice a year since I got the engine back.

I'm wondering if the oil pump is locked up, not letting the drive gear turn while it raises up on camshaft gear?

The gear will turn with the crankshaft, but it does seem to be bound up.   

Or maybe the hex shaft the drive gear has is twisted somehow where it goes into the oil pump?

It seems like like dropping the oil pan may be the best way to find out.   I don't have great access to the back of the engine, even with freakishly long arms. 

[Those]

I had the same issue. I had a 3 arm gear puller I was able to take apart and use 1 arm. Both ends had a hook so I was able to hook one end under the gear and tap up on the hook on the other end with a hammer.

[Dakota]

The oil pump gear is out.   I ended up dropping the oil pan and removing the oil pump (and the centerlink as well as the windage tray).

The pump came off easily.   With the pump removed, I was able to tap on the bottom of the gear shaft and pop it up.   Just for fun, I let it settle back in place, then tried to turn it out with a screw driver from the top - no go.  It seems to like staying solidly engaged with the gear on the back of the camshaft.  The gear teeth on the oil plump drive appear to be in excellent shape.

While I have easy access to everything, I'm going to play around with making a tool or a wire loop of some kind to see what I can do relatively easily to lift this gear out when I need to do it in the future.

Peaking around the inside of the engine, there was a good coating of break-in oil on everything.   I'm going to check the torque on the rod and main fasteners while I have access.

I have another set of pan gaskets to put into service.   The replacement pump gasket should be here by Friday.

[Chryco Psycho]

if it is a fresh rebuild the bushing maybe be tight & not sized right

[RUNCHARGER]

I hope the bushing didn't come out stuck on the drive.

[Dakota]

Best I can tell, there were no issues with the bushing.  It's still in the pump.  I was able to slide the gear shaft in and out of the bushing without issue.  There wasn't any sludge or anything else causing the shaft to stick. I'm going to try and check the shaft to make sure it's not bent.

[Dakota]

I had some limited success lifting the gear out with a magnetic pickup tool.  The magnet isn't quite strong enough to get the gear out completely, but at least I could get some movement from the top of the engine.   I've ordered a stronger "fishing magnet" to see if that will help let me pull the gear repeatedly.  The oil pump isn't going back in until I find something that works. 

More news when I have it.