Restoration
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4-speed transmission
Continued from Page 1
Shift Stops
Well, how do you inhibit this wear from reoccurring? Make certain that your shifter is adjusted properly. Unfortunately most of the Competition Plus shifters installed in our Pontiac did not come with this capability: shifter stop bolts. Hurst gave the "shade tree" mechanic a head start that makes the addition of shift stops easily achieved. The shifter body has holes stamped front and rear in the proper place to be used as pilot holes. Just drill, tap and install a 3/8-inch bolt and jam nut and you have added the shift stops.


With the shift stops installed it is time to reassemble the shifter linkage and adjust the shifter. This includes the tightening up of the earlier identified shift rod rattle. When making your trip to the hardware store for the 3/8-inch bolts and jam nuts for the shifter stops, you will also need to pick up a few new lock nuts and hardened washers, both flat and spring wave. You should have noted in your disassembly of the shift rods from the transmission levers that a spring wave washer was used to take up some slack. Over the years the spring gives way and the "some slack" turns into a lot of slack. We found these new heavier spring wave washers in the metric section at our neighborhood Ace Hardware.

Reassembly
Install the levers back onto the transmission with the new lock nuts and hardened washers being careful to not over-tighten the nuts. With a standard length wrench, you can easily put 15-20 lb.-ft. of torque on these. Next install the shift rods to the levers using the new spring wave washers. Do not tighten these up just yet. That is done during the final adjustment process.


Now affix the other end of each shift rod to the shifter levers. Before you install the spring clips, add a hardened washer to take up the slop. After you install the spring clips, take needle-nose pliers and bend up the ends of the spring clips. This will ensure the spring clip stays in place. Put the shifter into Neutral and slide in your alignment tool.


With the shifter in Neutral and the transmission in Neutral, tighten the nuts where the shift rods attach to the transmission levers. Remove the alignment tool and firmly shift through the gears. Return to the Neutral position and you will see that your alignment tool falls right into place.

Ready, Set, Go
The final operation is to set the shift stops. This is easily done, but one would be surprised at the number of shifters (with adjustable stops) that are improperly adjusted. First, make certain the stops (bolts) are backed out. Place the transmission in 1st gear then firmly shift down into 2nd gear. Tighten the stop bolt until it touches. Then back the bolt out one complete turn and tighten the jam nut. Repeat the procedure for the other stop by placing the transmission into 3rd gear. You'll now have firm positive shifts.


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Photo Guide
muncie m-20 wide ratio 4-speed transmission
The Muncie M-20 wide ratio 4-speed transmission equipped with the Hurst Competition Plus shifter. The shift rods were loose. After inspecting the linkage, it was time for disassembly. Note that there are no shifter stops on this factory-installed shifter.

Here is the worn forward shift lever removed from the transmission. You can see the spread area caused by numerous hard 1-2 power shifts. This increased interior dimension can result in the transmission detents not returning to Neutral.
transmission repair
With the damaged area brazed to fill the spread/worn area, hand file the shift lever back to its original size. Take your time, file and test-fit the lever until you have it right and tight being careful to not remove too much of the material.
shift lever repair
File fit back to its original interior dimensions the shift lever is ready to be installed.
worn shift lever 4-speed trans
In some instances, where the shift lever is not too worn or elongated, the metal can be swelled back to size using a center punch and ball peen hammer.
competition plus shifter
The Competition Plus shifter has holes correctly located front and back on the shifter body, properly positioned and ready to be drilled and tapped for the installation of shifter stop bolts.
shifter repair and replacement
The final drill size for the 3/8x24 thread tap is 21/64. Securely clamp the shifter in a vise. First use a pilot drill and then the 21/64 drill. Go slow to ensure a clean circular hole for the thread tap.
4-speed transmission tech
Tap the drilled hole with the 3/8x24 thread tap making certain to lubricate the tap as you create the thread. After the hole is tapped, use some carb cleaner and compressed air to clean any remaining filing from the shifter before installing the stop bolts.
shifter stop bolts
The shifter stop bolts are 1-1/2-inch 3/8x24 thread bolts. A jam nut is utilized to lock the bolt in place after adjustment.
shifter stop bolts install
With the shifter stop bolts installed you have successfully upgraded your shifter. Time to reinstall the shifter, upgrade the fasteners and adjust thing right.

Here is the standard wave spring washer compared to the new heavier spring washer used in connecting the shift rods to the transmission shift levers. The new heavier wave spring washers eliminate the rod rattle.
transmission shift lever install
The transmission shift levers are first installed onto the side case with new, hardened washers and lock nuts. Next, the shift rods are attached to the levers utilizing the new wave spring washers and nuts.
shift lever in neutral
With the transmission in Neutral, the shifter is placed in Neutral with the alignment tool in place to assure position.
shift rods and shift lever
Secure the shift rods to the shifter levers. Adding hardened washers reduces the slop in the linkage. Make certain to bend up the end of each spring clip for good insurance.
set shifter bolt stops
With the linkage assembled, it's time to set the shifter bolt stops. The front bolt stop is for 2nd and 4th gears while the rear bolt stop is for 1st and 3rd gears. To adjust the stops, place the transmission firmly into gear. By hand, run the bolt up until it touches the shifter lever then back the bolt out one complete turn and tighten the jam nut. Repeat for the other stop.
shift rods attached to transmission levers
The shift rods are now firmly attached to the transmission levers and the shifter. With the shifter stop bolts adjusted you can be assured of minimal wear on the transmission shift levers. You're now officially a shifty character.


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