RSTX-122958

Product information RSTX-122958

Timing Chain Tensioner / Timing Chain Extension Wear Indicator for M271

Special tool for checking the timing chain on all Mercedes M271.8 and M271.9 engines.
This timing chain tensioner for checking the timing chain extension allows for early diagnosis of chain extension without dismantling the engine.

Procedure:
- Remove the original chain tensioner; if necessary, remove the generator and the cover.
- Install the timing chain tensioner with 20 Nm, without the seal.
- Turn the engine 2 revolutions and determine the highest reading. This usually occurs at ignition OT 1 cylinder.
- To improve readability, we recommend fitting a rubber O-ring to the scale. This is shifted backward on the scale by sliding the measuring piston.

Test result:
A reading of 63 indicates a perfect chain drive, including rails, chain, and sprockets.
The timing chain must be replaced if the timing chain is extended or if the test value exceeds 75.

CAUTION:
The previously installed chain tensioner must not be reinstalled, as the pressure bolt is pressed into its end position during removal. Reinstallation would result in the timing chain being over-tightened. Please note that starting the engine is only permitted with the original Mercedes chain tensioner. The test tool must only be operated by hand and only in the direction of engine rotation. Failure to follow these instructions will cause the timing chain to be unintentionally skipped and the timing times to be adjusted, which may lead to engine damage!

Possibly required tightening torques:
Original chain tensioner: 40 Nm (replace sealing ring)
Measuring chain tensioner: 20 Nm (installation without sealing ring)

Suitable for chain tensioner comparison number; Mercedes Benz:
A2710500311, A2710500411, A2710500611, A2710500911

Suitable for the following engine codes:
M271

To be used as Mercedes:
W271589076300 / 271 589 07 63 00