Resetting Cam Chain TENSIONER
| 1 - Ratchet Clip |
| 2 - Groved Surface |
| 3 - Tensioner Piston |
The cam chain tensioner uses engine oil pressure to apply pressure to the cam chain tensioner arm and control cam chain slack. In the absence of oil pressure, such as engine start-up, the tensioner must still control chain slack until oil pressure rises. To achieve this an internal spring extends the tensioner piston from the tensioner body. To limit piston travel and account for normal cam chain wear, the piston has a groved surface with a ratchet clip that moves down the piston shaft from one grove to the next as the piston extends from the tensioner body. The groves in the piston surface are configured so as to allow the ratchet clip to move in one direction only and not allow the piston to retract back into the tensioner body. In order to reset the tensioner, the ratchet clip must be expanded so that the piston can be pushed back into the tensioner body.
WARNING use caution when the ratchet clip is expanded, the piston is free to eject from the tensioner. With spring force behind the tensioner and the ratchet clip open, the piston can become a projectile.
| 1 - Ratchet Clip |
| 2 - Snap-Ring Pliers |
The use of a bench vise may be required to compress the spring and push the piston back into the tensioner body.
- Working within the window opening of the tensioner body, spread the ratchet clip with the snap-ring pliers. The ratchet clip is now open, allowing free motion of the piston.
1 - Piston 2 - Tensioner Pin - While holding the ratchet clip open with the snap-ring pliers, push the piston into the tensioner body until the (special tool #8514A, Pins, Tensioner) can be inserted into the hole in the tensioner body which will hold the piston in the retracted position.