What is the concern about the VW 1.9TD engine common crank pulley failure?
The 1.9TD engines have an issue with the bottom crank pulley coming off the engine during operation. This happens because the keyway at the nose of the crankshaft wears allowing the crank pulley to move and oscillate. This movement eventually leads to crank bolt failure causing your harmonic balancer and crank pulley to come off during engine operation. Because the VW diesel is an interference engine, this usually results in bent valves and expensive head and or piston repair. Should you decide to run a 1.9TD (AAZ) engine in your application, ACME highly recommends modification to your 1.9TD crankshaft by welding up the keyway and machining the end of the crank to a “D” shape. This will allow you to use a later model TDI crank pulley eliminating the possibility of a future failure. Contact ACME if you need a crankshaft modificaiton kit for your 1.9TD (AAZ) engine.
