Oil pan drain "bung"

1959 - 1978, M151, M151A1, M151A2, Technical questions and discussions, regarding anything related to the M151.
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Balding Eagle
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Oil pan drain "bung"

Post by Balding Eagle » Fri Aug 20, 2021 12:57 pm

Hello fellow enthusiasts, I have a question and was wondering if anyone has ever experienced this problem...
I acquired a non-running project m151a1, started an oil change yesterday evening, was having trouble with the drain plug, it was pretty beat up and I was having trouble keeping a socket on it, decided to use an electric impact gun on it, it broke loose and I was able to drain the old oil, however, when I began to examine the drain plug, I realized the horror!!! Evidently my drain plug came out with the steel bung that was pressed? into the oil pan. How much trouble am I in? I need to put the bung in a vice and remove the drain plug out of it, maybe I can beat the threaded bung back into the gaping hole in my oil pan and presumably weld it back in?? Needing some advice.. and I'm not ready to pull the engine to replace my oil pan at this time. Thanks.


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Re: Oil pan drain

Post by Balding Eagle » Thu Sep 09, 2021 6:32 pm

Balding Eagle wrote:
Fri Aug 20, 2021 12:57 pm
Hello fellow enthusiasts, I have a question and was wondering if anyone has ever experienced this problem...
I acquired a non-running project m151a1, started an oil change yesterday evening, was having trouble with the drain plug, it was pretty beat up and I was having trouble keeping a socket on it, decided to use an electric impact gun on it, it broke loose and I was able to drain the old oil, however, when I began to examine the drain plug, I realized the horror!!! Evidently my drain plug came out with the steel bung that was pressed? into the oil pan. How much trouble am I in? I need to put the bung in a vice and remove the drain plug out of it, maybe I can beat the threaded bung back into the gaping hole in my oil pan and presumably weld it back in?? Needing some advice.. and I'm not ready to pull the engine to replace my oil pan at this time. Thanks.

steveperryman
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Re: Oil pan drain "bung"

Post by steveperryman » Fri Sep 10, 2021 7:41 am

Hi there...

Don't panic...

You can purchase, or fabricate a steel nut attached to a rubber grommet that overlaps the size of hole in the pan. , then the bolt (that also has a rubber grommet surrounding it) screws in and the 2 rubber grommets touch and compress upon each other and seals the opening.

There are a few ways to do this, I forget if the pan can be dropped without pulling the motor, if it can, the best thing to do is just replace the pan, there are lots available....


-Steve

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Re: Oil pan drain "bung"

Post by W. Winget » Fri Sep 10, 2021 8:31 am

I do not believe you cant pull the pan off with the engine in the vehicle, there's no clearance.
Measure the hole
Google "Rubber expansion plug" or hit a hardware store and buy one.
https://www.google.com/search?q=Rubber+expansion+plug
That should cover you until your ready to pull the pan and either weld the threaded portion back in, or just buy a used decent pan. If you were closer I would have one for you to just pick out of the pile of engines I have in the woods.
V/R W. Winget
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Re: Oil pan drain "bung"

Post by Rickf » Fri Sep 10, 2021 9:27 am

I think he is talking about a hole which is much bigger than those cheapie rubber deals are going to handle. No matter how you look at it you are either going to have to weld the original back in or replace the pan. Using an impact to remove a drain plug was not a very good choice of tools, you are working with sheet metal here. But you now know that so enough for that. Welding the original back in upside down into a pan with left over oil in it is not going to be a very good idea so either way the pan has to come off. You could jack up the engine enough to pull the pan but by the time you get that far you might as well pull the power-pak. I can have mine out in less than an hour by myself, it is not a hard job.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Oil pan drain "bung"

Post by svramselaar » Fri Sep 10, 2021 12:41 pm

hi

Rickf
you have the only best solution
weld it back with copper
1976 ? M 151 A2 AMG MUTT lost in acsedent
1978 M 416 A1 ( parkhurst ) trailer
1970 m151 A2 FORD BUDD tub
1957 Volvo sugga radio truck
M 274 mule HOME MADE MULE

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Re: Oil pan drain "bung"

Post by Rickf » Fri Sep 10, 2021 2:43 pm

Weld it with copper? I am thinking something may be lost in translation here. I have brazed with brass and I have welded with silicone bronze but I have never welded with copper. Never let it be said I have done it all though.
Personally if I absolutely had to weld it back in I would Mig weld it back with steel wire. Getting the close tolerances needed to braze it would be hard since it tore out, with Mig you can fill in the holes where needed. Depending on the damage I might just weld a patch over the hole after cutting it clean and then weld in a new plug made from a bolt, nut and washer with a gasket. Weld the nut to the inside of the pan over the hole you drilled for it. Then weld the washer to the bolt and put a gasket on it and wala, new drain plug.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Oil pan drain "bung"

Post by Balding Eagle » Wed Sep 22, 2021 11:05 am

Thank you all so much for the ideas and input. I went to O'Reilly Auto Parts and purchased an expanding freeze plug, stuck it in the hole and tightened it up. I filled engine with oil and its been holding oil without any leaks. I'm realizing that the repair plug will probably not last and is only a temporary solution. However, I have been able to run the engine for the first time since I purchased the mutt. On to my next project, the brakes ...


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