'39 trans with Linc Od ???
- Thread starter Charlie ny
- Start date
40cpe
Well-known member
The picture of the modified side shift posted by Bob C utilizes the stock, internal lockout. That setup is stock Mercury (just assuming here) except for the shifter.
expaver made the shifter and can explain any other mods done to the unit.
CarlG
Well-known member
There's a '48 Lincoln 3-speed with OD on the swap meet right now.
http://www.fordbarn.com/forum/showthread.php?t=177148
http://www.fordbarn.com/forum/showthread.php?t=177148
V8COOPMAN
Well-known member
expavr
Well-known member
The only modifications to the Merc transmission are replacing the shift arms that connect to the shafts going into the trans and changing to lighter springs in the interlock sleeve assy. Other than that the trans is stock and is capable of functioning as designed.
expavr
Well-known member
"Wrong approach. How would you avoid having to worry about the mainshaft?"
Hoop
IMO the starting point for this mod IS the mainshaft. Based on Merc 42's response it sounds like that hurdle is not a problem. That leaves adapting the Lincoln O/D tailshaft to the 39 case. I see the following details that need to be addressed for that mod to happen: 1. Access to the idler and reverse idler shaft retainer pins needs to be maintained. 2. An interface with the rail and the 1st/reverse fork in the trans needs to be engineered if the reverse lockout feature is to be maintained. 3. The design of the points of attachment on the 39 trans case and the configuration of the adapter to insure the integrity of the unit needs to be addressed . My gut reaction says 1 and 3 are manageable. Number 2 making the rail and toploader 1st/reverse fork function as the OEM reverse lockout design will take some thought. Regarding 2 if the use of the OEM designed reverse lockout feature isn't too important, the rail could be cut down to avoid contact with the fork in the trans. This would necessitate manually taking the trans out of O/D with the pull and cable when reverse is needed. I do this now when I use reverse, so that step isn't a big deal. With the cut down rail anyone operating in O/D would need to be aware that if they shifted into reverse the vehicle would be in a free wheel condition and wouldn't move in reverse. I'm looking forward to the development of this modification by yourself or Charlie ny. It looks like another way to skin a cat to get the benefit of O/D.
Les Williams
Hoop
IMO the starting point for this mod IS the mainshaft. Based on Merc 42's response it sounds like that hurdle is not a problem. That leaves adapting the Lincoln O/D tailshaft to the 39 case. I see the following details that need to be addressed for that mod to happen: 1. Access to the idler and reverse idler shaft retainer pins needs to be maintained. 2. An interface with the rail and the 1st/reverse fork in the trans needs to be engineered if the reverse lockout feature is to be maintained. 3. The design of the points of attachment on the 39 trans case and the configuration of the adapter to insure the integrity of the unit needs to be addressed . My gut reaction says 1 and 3 are manageable. Number 2 making the rail and toploader 1st/reverse fork function as the OEM reverse lockout design will take some thought. Regarding 2 if the use of the OEM designed reverse lockout feature isn't too important, the rail could be cut down to avoid contact with the fork in the trans. This would necessitate manually taking the trans out of O/D with the pull and cable when reverse is needed. I do this now when I use reverse, so that step isn't a big deal. With the cut down rail anyone operating in O/D would need to be aware that if they shifted into reverse the vehicle would be in a free wheel condition and wouldn't move in reverse. I'm looking forward to the development of this modification by yourself or Charlie ny. It looks like another way to skin a cat to get the benefit of O/D.
Les Williams
Hoop
Well-known member
Les, I am currently digging through my pile of postponed projects. What I meant by "wrong approach" is that the object, I figured, should not be trying to modify a "39 transmission" to accept a certain OD unit. I saw going the easier route of using the entire OD transmission and substituting a modified top-loader case into which all of the OD transmission gears/mainshaft would, of course, fit.
Your concerns about the reverse lockout routing have me questioning my memory ... so I'l be digging out some "study material" from under the work bench.
You mentioned getting rid of distractions. I hope you realize that building a top-loader OD transmission was itself a distraction that diverted me away from other distractions. My hobby is working on one distraction after another.
I appreciate your good work and will post some thoughts if something doesn't fall on me.
Your concerns about the reverse lockout routing have me questioning my memory ... so I'l be digging out some "study material" from under the work bench.
You mentioned getting rid of distractions. I hope you realize that building a top-loader OD transmission was itself a distraction that diverted me away from other distractions. My hobby is working on one distraction after another.
I appreciate your good work and will post some thoughts if something doesn't fall on me.
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Hoop
Well-known member
Les, had a hard time finding an OD transmission that was relatively easy to get to. My wife reminded me that there was one stored underneath the bed in the guest bedroom.
(Be lost without her.)
Your No. 2 .... easy. The rod is located so that 1/rev fork will push it to the rear when reverse is engaged. The OD unit's fork is wide enough to contact the rod; the "39" shifter top fork will need a small tab welded on to widen it and reach the rod.
I see the challenge being cutting the adapter piece (plasma) and getting a good weld to the case. Surfacing the rear after welding would be a minimal clean-up as needed since the front/back dimensions of the cases are the same.
(Be lost without her.)
Your No. 2 .... easy. The rod is located so that 1/rev fork will push it to the rear when reverse is engaged. The OD unit's fork is wide enough to contact the rod; the "39" shifter top fork will need a small tab welded on to widen it and reach the rod.
I see the challenge being cutting the adapter piece (plasma) and getting a good weld to the case. Surfacing the rear after welding would be a minimal clean-up as needed since the front/back dimensions of the cases are the same.
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