(21) Rotax m8 stop washer

🏎️ Full description: What is the purpose of this piece?

The m8 stop washer fills accurate mechanical functions for the Rotax Dd2 :

1. Maintaining the tightening torque: It acts as a mechanical brake. Once the nut tight at the torque, the washer prevents it from "turning" under the effect of high frequency vibrations of the engine.

2. Embase protection: It distributes the pressure of the nut on a wider surface and prevents the nut come from "digging" or mark the aluminum of the cylinder during tightening.

3. Thermal stability: Designed in a specific steel, it retains its pressure properties even when the cylinder reaches its maximum operating temperatures.

4. Specific Safety DD2: The DD2 engine having a particular architecture with its integrated gearbox, the maintenance of the cylinder must be irreproachable to prevent deformation of the seal plane.

💡 Michel's trick

"Do not make the classic mistake to go up your old whedings all crushed! A stop washer, it has some 'elasticity' or notches that eat with time. If it is flat like a crepe, it is no longer useless. My advice: to Every time you fall the cylinder for a piston, puts slices n ° 21 new. It costs three times nothing and it avits you to find a nut at the bottom of the tub in full race!"

🎓 TUTO: assembly and precautions

1. The direction of installation: Place the stop washer (No. 21) directly on the stud, against the cylinder base, before screwing the nut (n ° 22).

2. Cleanliness: Make sure there is no fat or oil on the washer. For it to "hang" well and do its brake job, surfaces must be dry.

3. Dynamometric tightening: Always use the couple recommended by Rotax (24 nm). The washer is calibrated to provide optimal resistance at this precise pressure.

4. Visual verification: During your controls between two sleeves, checks that the washer is always well plated. If you see a space, it's because the nut started moving.