Date: Tue, 6 Jun 2006 08:27:24 -0400 From: "James Rosenkranz" <fireglownospamsouth.net> Subject: Saab 900 Classic Timing chain issue
I have a 1989 Saab 900 16v NON-Turbo with 155K miles on it. Recently its begun to make some noises that appear to be related to the timing chain. I was hearing some random but frequent "pinging" noises when the engine was warm. The sort of sound you would get from striking an exhaust pipe with a screw driver. They sounded like they were coming from the area of the timing chain. Thinking it might be related to timing chain tension, I replaced the timing chain tensioner. The tensioner was extended 8-9mm. It is my understanding that 11-12mm would indicate a timing chain requiring replacement. With the new tensioner, I now have a loud, persistant rattling noise. This noise is more what I would think a noisy chain to sound like. I removed the new tensioner just to check the extention and make sure it was operating correctly. It measures 8-9mm as did the old tensioner. So, I need to understand what situation I am now faced with. Is the chain worn to the point it requires replacement? Are the guides worn? Is there life left in the chain in spite of the noise? Can the car be driven without fear of chain breakage or am I living on borrowed time? Advice much appreciated, jim