Magnetic Muncie fill/drain plugs -- M22 only ?

[Wayne M.]

I know we might have discussed this before, but I couldn't find it in the archives.

So, when the 3925661 cast number maincases came into use during the 1970-74 period, with drain plug bosses drilled, were they ALL magnetic (probably 2nd design with LISLE on a diagonal), or was it only the M22's ?

[Stuart F.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

We used to get our magnetic plugs from AMC back in the late 50's. Why did it take Chevy so long to find their value?

Nice photos Wayne.

Stu Fox

[Keith L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

hmmm, my 661 M21 has a drain plug. I assumed a previous owner drilled it. I will look at it closer.

[Joe L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Keith------


All '661' main cases were drilled and tapped for a drain plug.

By the way, you are going to have a VERY interesting challenge facing you when you try to remove either the drain or fill plug from this case. If you can get them out without having to resort to drilling them out I'll be amazed.

[Joe L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

I know we might have discussed this before, but I couldn't find it in the archives.

So, when the 3925661 cast number maincases came into use during the 1970-74 period, with drain plug bosses drilled, were they ALL magnetic (probably 2nd design with LISLE on a diagonal), or was it only the M22's ?

Wayne-------


I have an NOS '661' main case that I used to build the M-22 transmission for the "ZL-1". It was supplied with magnetic drain and fill plugs.

[Grant W.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Just wondering does anyone know what is the correct head marking for a 68 M22 case 660.

Thanks, Grant

[Keith L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Keith------


All '661' main cases were drilled and tapped for a drain plug.

By the way, you are going to have a VERY interesting challenge facing you when you try to remove either the drain or fill plug from this case. If you can get them out without having to resort to drilling them out I'll be amazed.

Yea, I Like to have never got the speedo bullet out. He tore up the m21 and had it laying in a shed for years. At least he kept it since it is the original. Other than soaking with PB blaster any other suggestions?

[Stuart F.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

The last time I had mine changed, I took it to a local oil change place that had the proper gear lube. The guys down in the pit struggled and swore in Spanish a lot, but finally got the plug out w/o any damage. The smiles never left their faces, but I knew what they were going through and just played dumb while I sucked on my Coke.

Stu Fox

[Joe L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Yea, I Like to have never got the speedo bullet out. He tore up the m21 and had it laying in a shed for years. At least he kept it since it is the original. Other than soaking with PB blaster any other suggestions?

Keith------


Like I say, if you can get them out any other way besides drilling them out, I'll be amazed.

The only other thing that MIGHT work is heat. You'd need to try heating the area of the case SURROUNDING the plugs until it gets VERY hot. Then, before it completely cools, try turning the plugs out. However, I don't think this will actually work and there is a risk to it.

As far as any sort of penetrating oil, hot wax, Kroil, etc., forget it! You'll just be wasting your time.

[Keith L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Keith------


Like I say, if you can get them out any other way besides drilling them out, I'll be amazed.

The only other thing that MIGHT work is heat. You'd need to try heating the area of the case SURROUNDING the plugs until it gets VERY hot. Then, before it completely cools, try turning the plugs out. However, I don't think this will actually work and there is a risk to it.

As far as any sort of penetrating oil, hot wax, Kroil, etc., forget it! You'll just be wasting your time.

Hey Joe, are you amazed??
No heat. PB blaster and time. Lots of both.

[Joe L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Hey Joe, are you amazed??
No heat. PB blaster and time. Lots of both.

Keith------


Yes, I am amazed! I have never had any luck getting these out that easily (even if it wasn't really that easily).

[Keith L.]

Re: Magnetic Muncie fill/drain plugs -- M22 only ?

Actually the plugs were the easy part. Getting the gears out was tough since the tranny was siezed up. Nothing would turn or slide off the shaft.
I will admit,I have been soaking this thing with PB blaster for months.