Machine shop forgot oil plug?

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Tylinol

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So, I'm following the pre-flight check on assembling my '69 318, and I'm having trouble determining if the main bearing oil galley plug is actually installed - it looks like it's just the block metal and I can see into passages that run parallel to it. Here are a couple photos; the bottom is about 1-23/64" from the surface of the block.

oil1.jpeg


oil2.jpeg
 
How does one get those plugs out ? I dont recall ever removing one ... they were alway out after hot tank at machine shop .
 
It seems like you would tap it out through the distributor clamp bolt hole at the top of the block Edit: meant the oil pressure sender hole. Here's another photo; it's the best my crappy camera could do looking at it through the oil filter housing hole

1C16B16E-974C-4D0B-9A72-619832D510FF.jpeg
 
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I only have about 10 FSMs... lol
I guess U could have referenced one .
 
I don't see anything meaningful in the '69 FSM about the plug, just a general diagram of the oil flow
 
I thought that plug was accessed through the oil sending unit hole next to the distributor? It's been a while since I've done anything small block related......but I will add this.

This is just one more example of what's separated between machine shop responsibility and assembler's responsibility. I actually WANT my blocks completely BARE when I get them back, so that I can assure ME, MYSELF and I......all THREE OF US that all the prep work is done. IMO, when you start talking about bolting or pressing things onto or into a block, that's part of assembly and not really on the machine shop.....unless of course you hire them to do that.

The reason I make this point is because more often than not, machine shops are always and I mean ALWAYS biased in their knowledge about one particular make of engines over the rest and more often than not, that's NOT Chrysler products. Knowledge is always key.
 
I hired them (amongst the other machine and cleaning work) to remove and replace the cam bearings and freeze/oil plugs. I don't have a cam bearing tool so this made sense, but in retrospect I should have just done the plugs myself - I ended up having to pull most of them again anyway to actually flush the block out properly after I got it back.

It seems from the diagrams that if the plug weren't installed at all, I would be able to see from the oil pressure sender hole clear to the other side of the oil pump hole on the main bearing cap, yes? If so, then it seems there is, as krazykuda said, a plug installed possibly upside-down. I'm guessing that the protrusion of this upside-down plug into the oil filter hole as shown in my third photo would affect my oil volume since it obstructs the hole slightly?
 
Tylinol said:
I hired them (amongst the other machine and cleaning work) to remove and replace the cam bearings and freeze/oil plugs. I don't have a cam bearing tool so this made sense, but in retrospect I should have just done the plugs myself - I ended up having to pull most of them again anyway to actually flush the block out properly after I got it back.

It seems from the diagrams that if the plug weren't installed at all, I would be able to see from the oil pressure sender hole clear to the other side of the oil pump hole on the main bearing cap, yes? If so, then it seems there is, as krazykuda said, a plug installed possibly upside-down. I'm guessing that the protrusion of this upside-down plug into the oil filter hole as shown in my third photo would affect my oil volume since it obstructs the hole slightly?
Click to expand...

And see, "here you are" in the predicament of not knowing 100%. The only way "I" would be satisfied at this point, would be to knock "whatever" might be in there out and pressing in a correct plug, the correct way, because at this point, you cannot trust another way. Just one person's opinion.
 
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Tylinol said:
I'm guessing that the protrusion of this upside-down plug into the oil filter hole as shown in my third photo would affect my oil volume since it obstructs the hole slightly?
Click to expand...

Maybe splittin hairs......maybe not. Something to think about.......a LOT of people go to a lot of trouble smoothing out and enlarging oil passages for better and increased flow. Now here you have something stickin out where normally something isn't. Splittin hairs? Maybe. Maybe not.
 
This plug is seriously in there - I'm giving it big wallops with my 5lb sledge and it's not budging or even denting on the main bearing side. That much force without any movement is the point where I say STOP and double-check that there's nothing that I could break by continuing to hammer it - for instance, there's no possibility of anything but the plug being in between the sender hole and the opening on the main bearing cap?
 
Tylinol said:
This plug is seriously in there - I'm giving it big wallops with my 5lb sledge and it's not budging or even denting on the main bearing side. That much force without any movement is the point where I say STOP and double-check that there's nothing that I could break by continuing to hammer it - for instance, there's no possibility of anything but the plug being in between the sender hole and the opening on the main bearing cap?
Click to expand...

That sounds like the point I would decide there's not a plug in it at all.
 
Maybe get on the phone and ask the shop what they put in there.
 
I may end up needing to get a borescope to verify this - it's hard to see in there, but what it *looks* like is that there was block casting on the path between the oil sender hole and the main bearing cap hole. My hammering punctured this casting, and I can see what looks like a little bit of space between where the casting used to be and the plug (or whatever it is).

If that's the case, I'm guessing this is the original "plug", since there would be no way to remove it without puncturing that casting.
 
Tylinol said:
I may end up needing to get a borescope to verify this - it's hard to see in there, but what it *looks* like is that there was block casting on the path between the oil sender hole and the main bearing cap hole. My hammering punctured this casting, and I can see what looks like a little bit of space between where the casting used to be and the plug (or whatever it is).

If that's the case, I'm guessing this is the original "plug", since there would be no way to remove it without puncturing that casting.
Click to expand...

Something has to be there. Look at this diagram. If there was no plug, you could go all the way out the oil sender hole.

SMALL CHRYSLER OIL PLUG.jpg
 
Great diagram here, plug should be 2 5/16" deep in the main oil galley hole. ^^^

Screenshot_20210731-170742_Chrome.jpg


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Here are some pictures, the white cord is the path from the oil pump rear main galley to feed the oil filter canister.

Oil is then filtered and sent to the rest of the engine from there.

The galley plug needs to be in deep enough to allow the oil pump main bearing galley to access the oil filter feed galley.
(Not Block It)

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I am measuring 2 5/16" to the bottom of the plug cup from the main bearing cap face up. Finished picture here. ^^^^^

You can also see the oil galley port to the oil filter in this plug picture too.
 
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So, whatever it is that's in my block is 7-3/4" from the top of the block and 1-23/64" from the bottom. I think I can also see the ridge of the plug a little bit when I look down in the oil sender hole, but it's hard to tell. It really seems like there's an upside-down plug in there, but whatever's in there almost can't be aluminum - it didn't deform in the slightest with me walloping it with the hammer, hard enough that I eventually bent the rod I was using to reach it. Unfortunately the machine shop is closed till Monday, so I can't call them for any insight yet.

That said, I have a suspicion that this is the original plug. The flat surface looks different than anything I've seen in the kits. I don't think there's any way for me to hammer it out, so I may be stuck between leaving it (since it's only partially protruding to the oil filter gallery) or drilling it out and trying to collapse it (which carries its own risk). I'd feel better if I could determine for sure if it's an original plug, since the engine did run just fine for 50 years.
 
See if you can blow air pressure back from the oil filter feed port to the rear main galley.

See if it feels like there is enough flow there to supply full oil flow to the rest of the engine. (and you do not want the air pressure test exiting up through the oil pressure sending unit hole at the same time)

If not your machine shop can easily drill out whatever plug is in there .570ths drill hole, and properly plug it to the proper depth with the replacement stamped steel plug.

Good Luck with your project.

☆☆☆
 
The arrow (I think the part that looks ridged in the photo) is pointing to the oil bore; the top of the plug is the very bright white disc above that (my light is reflecting off it)
 
After looking closely it looks like it was installed with the cup side away from the oil flow and close to the passage possibly to smooth out the flow and might be a good idea. (?)
 
If you look at the diagram I posted, the oil galley shrinks down going towards the top. The plug is in that area. In short, I believe someone used an incorrect size plug and installed it in the part of the galley that necks down, instead of further down and away from the intersection of the galley going to the filter area. Did the shop do it? Is it something the factory did? Who knows? It looks like that passage going to the top where the sender is, is blocked, like the factory intended regardless.
 
Look. This is REAL simple. Block off the oil galley coming FROM the pump in the filter boss area with your thumb and apply air pressure to the hole in the block where the main cap bolts. If you get air escaping from anywhere EXCEPT trying to come out the hole you have blocked with your thumb, you need to do something. If not, send it.
 
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