:banghead: :banghead: The previous owner sheered off the drain plug on my M-21. I replaced the fill plug after I used a vacuum pump (brake bleeder pump) and removed all the old fluid then topped it off with fresh fluid. So tonight I decided to finish the job as I just bought new drill bits, easy out and tap kits. Well the drain plug is 5.5" inches from the right exhaust pipe and just aft of the header to pipe connection making any use of a standard drill impossible. Maybe with a angle drill head I could do it but even then it's tight. The exhaust system is in good shape but welded one piece so I can't remove it without cutting the exhaust in 2 and getting a welder. the tranny performs flawlessly and had been overhauled prior to service so I don't want to disturb it. Basically I'm screwed until I finally need a clutch job or when the exhaust starts rusting out then I can get at replacing that drain plug. The procedure for sucking out the fluid is painless and revatively fast but I doubt it's ability to get all the thicker goop out of the tranny during fluid changes.
Maybe it's time to consider getting those ceramic coated hookers and Walker chambered exhuast I've been dreaming about just so I can get at that plug.

:rolleyes:

okay here are the pics, taken with me reaching under car under the ground and blindly shooting up, took 20 pics just to get 3 good ones.

okay broken off drain plug, note kick-out from case for draining. Note also the threads still visible and look how small the plug is compared to pic-2.


Fill plug. Plug is much wider.

And here is the plugs, bigger one fill and smaller one I think will fit once I got the broken off one out.





[Modified by Cali,68,L-79, 7:57 PM 4/14/2004]

 

your transmission has a drain plug? (mine doesn't)... there is a muncie article around here somewhere that tells you when they first added drain plugs to these things. MJ

 

There's a small ripped up circular section in the exact spot where the drain plug was on my old 77. I can see it's threaded and that the surface of that plug is ripped and rough as if it had a 4-sided end that broke off, certainly not the finish one would get out of the factory. You say the 1968 Muncie's had no drain?

 

My 68 M21 doesn't have a drain plug. Is that the correct tranny or is it a replacement?

 

http://www.corvettemagazine.com/1999...2/munciep1.asp

 

I'll have to take a picture tonight and show you what I mean.

 

David, I assume you mean the fill plug on the passenger side of the transmission? The one that is a few inches up from the bottom of the case and is threaded in horizontally?

Shannon

 

The bottom plug must be drain while the top is fill. I'll take pics tonight.

 

My 69 M20 has the 2 plugs. Bottom for drain, top for fill.

 

TTT

Pics of broken off plug above.

 

David,

Here are two pics of my original '69 M-20 case. I don't think that it's a drain plug at all. It may be something related to how the case was cast and machined. I know for a fact that mine is not a plug, because I just rebuilt the tranny this time last year.

 

In photo 2, is that a stress crack along the front left quarter of the plug? Don't panic, it might just be where some oil has accumulated. But worth wiping clean and checking out.

Lowcountry Corvette
www.LowVette.com

 

An expert needs to confirm this, but I believe that the transmissions without the drain plug still had the casting with the place for the drain plug. It just wasn't drilled out. So Cali, I think in your pic there is no plug there, and never was. You can tap one if you want. :) MJ

 

That is consistent with my recollection - That's the place where the drain plug WOULD be if they put one there. :) MJ

 

Here is my late 69 M20. The stamped #s match the vin. Was this 2nd drain plug added, or original? It looks offset like the top one.


[Modified by lostpatrolman, 7:30 AM 4/15/2004]

 

sb69coupe. you may be right but I think that the factory was or may have had plans on making that a drain plug. Reason I say that is becuase there is a kick-out built off the bottom of the case which is consistent for a drain. I mean why would that piece stick way off the case otherwise and what purpose does that round hole (filled in) serve????? You had the tranny open so what's near that hole anything? Would drilling thru it and taping a drain in hurt anything down there?

 

LPM looks like the guys think your M20 came with a drain plug while my M21 did not. However my last m20 drain was not offset like yours, not sure why however if it works and doesn't leak no problem.