DZAUTO
Mar 21st, 08, 5:09 PM
Here is an example of something that I've mentioned several times when telling about rebuilding Muncies.
All pre-70 Muncies are built with a donut magnet glued to the bottom of the case. All Muncie cases have a lower boss for a drain plug, but the drain plug did not come standard until 1970 (pre-70 M-22s had drain plugs).
When I rebuild a Muncie, I pry out the donut magnet, drill and tap a hole in the lower boss for a drain plug and install a magnetic drain plug. Period!
In 40+yrs of rebuilding 4spds, I have only had ONE person tell me not to install a drain plug (it was the original Muncie in a totally numbers matching 68 435hp/427 Vette).
It is very rare for that donut magnet to come loose, but when it does, BYE-BYE Muncie!!!!!!!!
Almost everything in this Muncie was destroyed or damaged beyond repair.
The case is not worth trying to repair.
Cluster is junk.
Input has busted teeth.
The rear reverse idler gear has busted teeth.
The inside reverse idler gear has EVERY tooth sheared off.
Teeth on 1st gear are chewed (but none broken off).
Second and third gear teeth are pitted.
The midplate is junk.
The syncro splines are packed with powered metal particles.
The bearings are junk.
About all that is useable is the main shaft, snap rings, bearing cage for the rollers between input and main shafts, and reverse slider gear.
Below is a photo of a donut magnet that I removed from a Muncie sometime in the past. Those 2 masses are what is left of the magnet (and a mass of metal particles) that came loose in this Muncie and tore apart a perfectly good 69 M-20! The other piece is a brand new magnetic drain plug that I install in all rebuilds that don't have a magnetic drain plug.
The bottom photo is the guts piled in a pan and you can see the damaged gears/teeth.
So, when you rebuild your Muncie, or have it rebuilt, remove the donut magnet and install a screw-in magnetic drain plug.
http://i65.photobucket.com/albums/h219/DZAUTO/Driveline/100_1406.jpg
http://i65.photobucket.com/albums/h219/DZAUTO/Driveline/100_1407.jpg
Oh ya, if this sounds like I'm using scare tactics----------------------------I AM!!!
All pre-70 Muncies are built with a donut magnet glued to the bottom of the case. All Muncie cases have a lower boss for a drain plug, but the drain plug did not come standard until 1970 (pre-70 M-22s had drain plugs).
When I rebuild a Muncie, I pry out the donut magnet, drill and tap a hole in the lower boss for a drain plug and install a magnetic drain plug. Period!
In 40+yrs of rebuilding 4spds, I have only had ONE person tell me not to install a drain plug (it was the original Muncie in a totally numbers matching 68 435hp/427 Vette).
It is very rare for that donut magnet to come loose, but when it does, BYE-BYE Muncie!!!!!!!!
Almost everything in this Muncie was destroyed or damaged beyond repair.
The case is not worth trying to repair.
Cluster is junk.
Input has busted teeth.
The rear reverse idler gear has busted teeth.
The inside reverse idler gear has EVERY tooth sheared off.
Teeth on 1st gear are chewed (but none broken off).
Second and third gear teeth are pitted.
The midplate is junk.
The syncro splines are packed with powered metal particles.
The bearings are junk.
About all that is useable is the main shaft, snap rings, bearing cage for the rollers between input and main shafts, and reverse slider gear.
Below is a photo of a donut magnet that I removed from a Muncie sometime in the past. Those 2 masses are what is left of the magnet (and a mass of metal particles) that came loose in this Muncie and tore apart a perfectly good 69 M-20! The other piece is a brand new magnetic drain plug that I install in all rebuilds that don't have a magnetic drain plug.
The bottom photo is the guts piled in a pan and you can see the damaged gears/teeth.
So, when you rebuild your Muncie, or have it rebuilt, remove the donut magnet and install a screw-in magnetic drain plug.
http://i65.photobucket.com/albums/h219/DZAUTO/Driveline/100_1406.jpg
http://i65.photobucket.com/albums/h219/DZAUTO/Driveline/100_1407.jpg
Oh ya, if this sounds like I'm using scare tactics----------------------------I AM!!!