Changing a shifter seal and o ring on FMX trans

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1971 Mach I
OK Guys,

Being an engineer with a lot of time on my hands, I decided to change my leaky shifter seal on my FMX trans.  Using info I found on this site as well as bits and pieces from other sources, I created a manual using lots of my own pictures and discriptions.  Just in case I am ever stupid enough to do this again.

See attached, hope it can be of use to others.

Mac

Replacing the shifter seal.pdf

 

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OK Guys,

Being an engineer with a lot of time on my hands, I decided to change my leaky shifter seal on my FMX trans.  Using info I found on this site as well as bits and pieces from other sources, I created a manual using lots of my own pictures and discriptions.  Just in case I am ever stupid enough to do this again.

See attached, hope it can be of use to others.

Mac
Very Good tutorial on a common problem. Thanks for all the good work!!!!!!  You will help many.

 
Nice write up . FMX can be fiddly but are a good trans

 
OK Guys,

Being an engineer with a lot of time on my hands, I decided to change my leaky shifter seal on my FMX trans.  Using info I found on this site as well as bits and pieces from other sources, I created a manual using lots of my own pictures and discriptions.  Just in case I am ever stupid enough to do this again.

See attached, hope it can be of use to others.

Mac
Something that I discovered after posting this repair write up.  After trying to reinsert the detent sping and plunger into the trans housing many times plus using all the words that the Army taught me (along with a few new ones I made up) I stumbled onto a good solution.

Coat the detent spring with a light coating of grease, just enough to get it to stay in place once you reinsert it into the housing, the take a short (say 4" long) piece of fuel line, split the end about 1/4" back two places (180 deg apart) then position the detent plunger round nose side down into it.  Put a dab of grease on the flat end sticking out of the fuel line.  Now hold the torsion lever to one side and reinsert the plunger.  Move the fuel line to one side as you reposition the torsion lever under the plunger to keep it in place.  After reinstalling the manual shaft nut, I used the end of a 1/4"drive socket extension to get the plunger into the detent slots in the torsion lever.

Mac

 
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OK, since I was changing the seal and oring, I decided to cover all the bases and replace the oring on the dip stick tube just to play it safe.  For two day I soaked the junction where the tube went into the trans case, remove the one bolt on back of the head that held it in place.  Tugged, pulled, swore and repeated that process with no luck, so since the trans pans was still off, I took a block off wood and ball peen and tried to "persuade" the tube to come out.  Nothing!!  Finally after looking at the dog gone thing from below, I discoved this tube will never come out.  See attached pictures, when my trans was built, this tube was "staked" in place!   So it you decide to pull yours beware.

Mac



 
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