Oil Pan Plug Nut--What Should I Do?

[Not Jonathan]

Hope everyone is doing well,

Went to do an oil change and to my dismay, the nut for the oil pan plug fell off inside the pan. Does anyone have any ideas for what I should do? Seems that the only way is to pull the engine and either repair or replace the pan, hopefully with one that has a bung that is welded all the way around!

If anyone has any tips about dropping the pan without pulling the engine, let me know. Looks like the motor mounts are in the way, not to mention whatever difficulty the pickup may cause. Obviously the center link would have to be pulled, but I'm curious to see what you think.

Edit: 360 Small Block LA

 

[fasjac]

Are you talking about the drain plug/bolt fell back into the oil pan when taking it out to drain the oil ? I may be missing something here. And did it have some type universal plug?

 

[Not Jonathan]

Are you talking about the drain plug/bolt fell back into the oil pan when taking it out to drain the oil ? I may be missing something here. And did it have some type universal plug?

It's the stock center sump pan. Whatever fitting that has the thread has fallen off into the pan, so when I look through the drain hole I don't see any threads. I can stick my pinky in and feel the nut/threaded piece. As of now my plan is to try and support the engine on one motor mount and a jack with 2x6 on the pan, remove the passenger side mount, grind for more clearance, and attempt to drop the pan from the bottom. Hopefully an exhaust shop can either weld in a new bung or weld in the piece that has fallen.

 

[BuckeyeCuda]

At this point, I would just bite the bullet and replace the oil pan with a new, factory-style pan. Not very expensive and will have a new oil bolt plug. You will remove the pan anyways, so this will eliminate any rust or other deterioration on your original pan.

 

[challenger6pak]

It is not that bad of a job to remove the pan with the motor in place. Engine headers make it more difficult. Remove the center link and unbolt the pan. I would lower the pan as much as possible before any grinding or jacking of the motor. You may be surprised how little you have to do to get it loose.

 

[rogue]

might be able to grab it and extract it with a magnet.... new pan seems to be warranted though

 

[fasjac]

It's the stock center sump pan. Whatever fitting that has the thread has fallen off into the pan, so when I look through the drain hole I don't see any threads. I can stick my pinky in and feel the nut/threaded piece. As of now my plan is to try and support the engine on one motor mount and a jack with 2x6 on the pan, remove the passenger side mount, grind for more clearance, and attempt to drop the pan from the bottom. Hopefully an exhaust shop can either weld in a new bung or weld in the piece that has fallen.

 

[fasjac]

Oh, got it. Definitely time for a new pan. Even if you could fish out the old one and weld it back with no leaks etc.
I’ve never heard of that happening on an oil pan. Bizarre man, oh well, stuff happens.

 

[fasjac]

If you could fish it out with a magnet or thin grabber cable, parts stores usually carry a universal type oil pan plug. That may work if the edges of the broken pan aren’t too jagged. Only if you need to move the car though.

 

[Not Jonathan]

Thanks for the replies everyone. This is today's project so hopefully I'll be able to report back with some good news. It looks like a previous owner did some fabrication on the motor mounts that makes a tight fit to the oil pan. I've removed the passenger side and cleaned it up. After re-installing it, maybe I will have enough room to get at the bolts and drop the pan.

As for a new pan, does anybody have recommendations? I was looking at the summit stock replacement and the milodon "stock" replacement. I hesitate with those because I'd prefer to use the stock pickup--I have no idea if the pickup could even be changed in the car. Not to mention the summit pan has a similar looking nut on the inside and I'd hate to ever encounter this problem again!

 

[fasjac]

I use Milodon on my 500 stroker and like it. Summit has you covered. I have a couple stock bb pans but, no sb

 

[Not Jonathan]

Well here was the culprit! Was able to get the required clearance just from modifying the passenger side motor mount slightly. Still debating on whether I will try to refurb this pan or order one tonight from summit.

Would anybody happen to know if the oil pump can be lowered from the bottom of the engine while it is in the car, and then the pickup tube removed? I don't want to destroy any gasket that I can't replace from the bottom of the motor. Would it be worth picking up a new pump too while it's opened up? Appreciate the input.

 

[rogue]

not sure about the pickup as far as clearance... the oil pump bolts in from the bottom... it's driven by a shaft descending from an attached gear driven by the cam which also drives the distributor. might be a bit tricky to remove and re-install new

 

[Chryco Psycho]

Oil pump is easy to drop down , how was the oil pressure before , how many miles on it ? you can take it apart & inspect it .
If you decide to replace it get a Melling pump & do not get a high volume but high pressure is a good option

 

[Not Jonathan]

Oil pump is easy to drop down , how was the oil pressure before , how many miles on it ? you can take it apart & inspect it .
If you decide to replace it get a Melling pump & do not get a high volume but high pressure is a good option

I have no idea how many miles are on this motor. The second previous owner of my Challenger swapped in the 360 LA, so there's no telling if it's a high mileage truck motor, etc. The oil pressure is lack luster. On the bright side (I guess?) I cleared a bunch of stuff out of the pickup, so hopefully that will make a marginal improvement. I had an oil analysis done awhile ago that would indicate something being gravely wrong, but the car has always run nice. Maybe something is on its way out, but I must address that down the road. The analysis was high in lead and iron.

When dropping the pump, does the intermediate shaft have to be removed? What I'm understanding as of now is: properly pull the distributor, pull the intermediate shaft, drop oil pump from below. Is this correct?

Would you recommend that I check anything else from underneath while I have the pan off? Nothing looks out of the ordinary, no crazy play in the rods or anything. They do have little side to side play on the crank journal, but from what I understand this is normal.

 

[704406]

The oil pump just unbolts and you can remove it. you don't have to pull the distributor or intermediate drive shaft. Chryco psycho is correct high pressure pump, not high volume.
I'd buy a new pickup as well, you can't see half the screen to see if it's compromised or torn.
Do not use a gasket where the pump bolts to the rear main cap.
Prime the pump with clean oil before reinstalling it.

 

[Not Jonathan]

The oil pump just unbolts and you can remove it. you don't have to pull the distributor or intermediate drive shaft. Chryco psycho is correct high pressure pump, not high volume.
I'd buy a new pickup as well, you can't see half the screen to see if it's compromised or torn.
Do not use a gasket where the pump bolts to the rear main cap.
Prime the pump with clean oil before reinstalling it.

I referenced the service manual and found this image. Just to be very clear, the bolts holding the pump in can be undone and the pump can be dropped while everything else stays in, right? And then when re-installing, I just need to make sure the hex lines up with the shaft? The manual then says tighten to 30 ft-lbs.

Thanks again for walking me through this. This is my first time seeing the bottom end in person so I am trying to be extra careful!

 

[704406]

Thats correct. The shaft is 5/16 hex so its easy to engage the pump to the drive, make sure the pump is flush to the main cap when tightening the bolts.
I've been a mechanic since 1974 and I've never seen that piece come loose from a oil pan before, I guess there's a first time for everything!

 

[Not Jonathan]

Just to finish the thread off:

Dropped the oil pump and pickup and picked up the Melling replacement parts. When re-installing, I first slipped the hex shaft on, then rotated the pump so the bolt holes would line up, then slide the part around the shaft into its bore, then put in bolts to spec. Simple job, really appreciate all the help! I was shocked by how much junk was in the pickup, I think half of a valve cover grommet must have fallen inside the engine at some point. It was definitely a good call to replace those parts.

For reference, I attached the nut to the oil pan with pipe solder. After prepping the surfaces, I heated both with a torch and then fed the solder. I then re-heated the joint and let it cool a few times to make sure there was a good amount of surface contact. It seems that it will hold up, the advertised melting temp is 460 degrees F.

 

[moparman31]

the plate that is spotwelded to the pan is what your referring to as the nut. You need to pull the pan to replace it or use a leaking self tapping plug which is highly not recommended. You can unbolt the engine mounts lift the engine with a jack at the balancer and possibly slide out the pan. Seen it done 100s of times while working in the dealership