Tool
Shimano dynamo housings can be opened with a 32 mm headset spanner. However, the manufacturer also offers the special TL-DH10 ring spanner for this purpose.
Open axle
First open the axle on the non-contact side (left): Use a 15 or 17 mm cone spanner and 17 mm open-end spanner to loosen the lock. The right-hand bearing remains untouched.
Remove axle cone
Unscrew the lock nut and axle cone. The ball bearing is covered with a sealing ring: Carefully lever it out of its fit. Make a note of its installation position.
Open the housing
Now turn the wheel over, carefully thread the ring spanner over the contact lug on the right-hand side of the axle and place it on the hexagon of the dynamo cover.
Loosen the screw connection
Hold the impeller firmly and turn the spanner anti-clockwise. The housing cover, including the inner workings and axle, will now slowly rotate out of the hub sleeve.
Dismantle dynamo
Carefully pull the dynamo unit by the axle out of the housing. Take care not to lose any balls from the open bearing opposite.
Clean internal unit
Allow the dynamo unit to dry well if you discover moisture on it (hair dryer). Then spray the unit carefully with WD40 or spray wax as rust protection.
Clean the sleeve
Also wipe the inside of the hub dry if it is damp. Spray on a coat of spray wax or WD40 as rust protection.
Lubricate thread
Use assembly paste on the hub thread before assembly. This makes the cover turn more easily during installation and prevents it from corroding even after a long period of time.
Close housing
Insert the housing cover by turning it backwards in order to approach the start of the flat thread without tilting. Finally, tighten the cover to approx. 35 Nm.
Grease axle bearing
Fill the left-hand axle bearing with viscous bearing grease and press in the bearing cover in the correct position. Screw on the axle cone and nut and lock the axle without play.
Check barrel
Finally, allow the wheel to rotate in your hand as a test: There must be no axle play and the axle should not run rough due to excessive tension.
