Rubber oil pan plug
#1
Racer
Thread Starter
Rubber oil pan plug
Went to change oil in my new to me 81. Much to my surprise i found this rubber oil pan plug installed. Could not believe what I was looking at. Anyone ever seen this and have any idea how to remove it? I dont want to break it and have some of inside the pan.
Bubba at work again...
I plan to replace the pan if i cant repair and install over size plug. It currently does not leak but i will mot drive it with that rubber plug.
I plan to replace the pan if i cant repair and install over size plug. It currently does not leak but i will mot drive it with that rubber plug.
#2
Race Director
Member Since: Apr 2011
Location: North of Toronto - Ontario
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That's one of those repair plugs that works kind of like a bilge plug in boat. There is supposed to be a wingnut, washer and threaded shaft in it that pulls the back of the plug in tight. I've only seen a couple on really old stuff and they looked like that... the bolt broken/rusted off.
There's no way of removing it except prying it out, IIRC the inside is bulb shaped and larger than the hole so they really had to be forced in and then when tightened it puffed up even larger to help seal.
50/50 it'll tear and leave chunks inside but it's not likely to fall out either, been in there for awhile already
M
There's no way of removing it except prying it out, IIRC the inside is bulb shaped and larger than the hole so they really had to be forced in and then when tightened it puffed up even larger to help seal.
50/50 it'll tear and leave chunks inside but it's not likely to fall out either, been in there for awhile already
M
#3
Racer
Thread Starter
Thanks Mooser, I already have ordered a new pan and gasket. Cant take a chance i will leave debris in pan. Be a good time to change the oil pump too.
#5
Racer
Thread Starter
#6
Team Owner
FWIW, the god news is that because the engine sits so far back, in a Corvette chassis, the oil pan R&R isn't that big of a deal. You will have to disconnect the center link of the steering gear, so it drops down a couple of inches, giving you room to slide the pan out. However, you won't have to lift the engine.
If you're looking for stuff to do, "while you're in there", I'd change the rear mail seal....
If you're looking for stuff to do, "while you're in there", I'd change the rear mail seal....
#7
Racer
Thread Starter
FWIW, the god news is that because the engine sits so far back, in a Corvette chassis, the oil pan R&R isn't that big of a deal. You will have to disconnect the center link of the steering gear, so it drops down a couple of inches, giving you room to slide the pan out. However, you won't have to lift the engine.
If you're looking for stuff to do, "while you're in there", I'd change the rear mail seal....
If you're looking for stuff to do, "while you're in there", I'd change the rear mail seal....
#8
Would be less inclined to change the oil pump and more interested to see how the rod bearings look, especially for the two front cylinders as they are the furthest away from the oil pump.
#9
Le Mans Master
Same with the rear main- if it's not leaking now. (it probably will at some point, but it's just a pan gasket and a seal later)
#10
Team Owner
Something I just thought of, should you decide to change the oil pump....replace the OE oil pump driveshaft, the one with the fragile plastic collar, with one with a metal collar. Both Melling and Moroso make them.
#11
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Now's a good as time as any to start a frame off
M
M
#12
Team Owner
With respect to the oil pump, OK, maybe it doesn't need to be replaced, but if I was already in there, I'd inspect the plastic locating collar on the pump's driveshaft. They're known to get brittle over time, and sometimes break. A shaft with a metal collar will eliminate that possibility, and again, is a relatively quick task.
#13
GM Cert Corvette Tech
Pro Mechanic
Went to change oil in my new to me 81. Much to my surprise i found this rubber oil pan plug installed. Could not believe what I was looking at. Anyone ever seen this and have any idea how to remove it? I dont want to break it and have some of inside the pan.
Bubba at work again...
I plan to replace the pan if i cant repair and install over size plug. It currently does not leak but i will mot drive it with that rubber plug.
I plan to replace the pan if i cant repair and install over size plug. It currently does not leak but i will mot drive it with that rubber plug.
Last edited by Douglas Mariani; 04-24-2018 at 09:53 AM.
#14
Racer
Thread Starter
That's an old style oil pan plug repair. There was a "screw driver style tool to remove it. since you just bought the car check the car for something that looks like a screwdriver. You push it in and turn and it will come out. I saw many of them back in the day...
#16
Racer
Thread Starter
I yahoo'd the patent number - https://patents.google.com/patent/US3307731A/en
Harry invented it in 1967 -
Harry invented it in 1967 -
the info was appreciated, thanks
#17
Racer
Thread Starter
Finally had a chance to investigate today. Pulled out rubber plug with my hand with very little effort. Standard 1/2 x 20 was too small. I stepped up to the 1st oversize and cut new thteads, problem solved. Thanks everyone.
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#18
GM Cert Corvette Tech
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#19
Nam Labrat
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