The following will walk you through a series of steps:
To unlocking a TKO that may have bounced into gear during shipping or has a synchro ring that has rattled tight to a gear.
During the Shipping process, a TKO transmission can get bounced around in its box. From time to time a shift rail can be bumped into gear on its own or a synchro ring pushed onto gear locking it tight. Without oil, the ring becomes locked. The following procedure will help diagnose the problem and several solutions to correct the issue.
Before diagnosing a potential problem… remove the shipping plug from the rear of the transmission by pulling with duckbill pliers.
Be careful not to accidentally grab the lip of the output shaft seal.
Grab the black rubber plug that is past the black output seal and pull a little on one side, then the other.
Checking for a bumped shift fork/rail.
Once the plug is removed, rotate the input shaft counter-clockwise. It should spin easily. Push the shifter forward into 3rd gear. Rotate the input shaft counter-clockwise. It should spin easily. Place the shifter into 4th gear. Rotate the input shaft counter-clockwise. It should spin easily.
Move the shifter into 1st and 2nd gear. Rotate the input shaft counter-clockwise. It should spin easily.
If you find the stub will not shift into any gear (try them all, usually with a lever installed for ease) then one of the shift rails has moved from the neutral position during shipping.
To confirm this the lever will only detent left or right and not move forward or backward.
Remove the middle silver 5-sided plate and inspect the shift-lug positions.
They should all be straight across from each other. If one of them is out of position using a screwdriver to reposition. It should click into the neutral position.
At this point, you would be able to shift into all gears.
Checking for a stuck synchro ring
A stuck Synchro ring will only allow you to rotate the input shaft in neutral and a single gear. If more than one blocking ring is stuck, the input shaft will not turn in neutral or any gear.
If only one blocking ring is stuck, you determine which one by shifting into each gear and rotating the input shaft. The input shaft will turn in the gear that has the stuck blocking ring.
This simple problem can be fixed in a couple of ways. With a shift lever installed temporarily for ease… move the lever in and out of all the gears you can, multiple times.
Usually, this frees up the stuck ring or rings. For a single stuck blocking ring, focus on shifting in and out of this gear multiple times.
Another way to free up stuck blocking rings is to shift the transmission into a gear the input shaft will not rotate in. Install the clutch disk on the splines and rotate back and forth to shock-load the gears. The blocking rings should pop loose.
On rare occasions, the synchro ring is locked on the gear so tight that the ring will need to be pushed off the gear.
By removing the two forward covers, locate the locked bronze synchro ring with the slide ring during the shifting procedure noted earlier.
With the transmission in neutral, use a small flat blade screwdriver and place it between the gear and the flat edge of the ring.
Give the screwdriver a twist and walk it around the ring to free it up. Clean all surfaces and seal with Ultra black or gray RTV sealant.
Before installing the bolts, make sure to remove any extra sealant on the end of the bolts to prevent damage to the case.
If the ring is not freeing up, please contact us for further guidance.
Let us know if you had to perform this procedure in case of any additional issue related to shipping or warranty.
As always, we’re here to help and can guide you thru the above process and any other related parts and installation issues.
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