I just bought a 1998 Grizzly 600 that needed the engine put back together. I have the Yamaha service manual, but it doesn't give me the info that I am looking for. I am lining up the timing marks to install the timing chain. You are supposed to set the "I" mark on the crankshaft even with the pointer on the crankcase housing according to the service manual. The problem I am having is that the crankshaft has 3 "I" marks on it. I can't see any difference between the 3 marks and I don't know which one to use. I put a screwdriver in the spark plug hole to see when the piston was at TDC. It stops moving upward after the second mark, but before the third mark. The second and third marks are only about an inch apart. Does anyone have any experience with this? Any help would be much appreciated!

 

mine needs to be lined up with the third mark.

 

Maybe the timing section of the manual says what each mark stands for? In most cases the advance line is not labled but, you should be able to see a T and F. It should be | , F , T first for advance fire (higher rpm), second one for retarded (idle) fire, and third for top dead center

I would agree with Quadking250x. The Last mark is almost always TDC. Install the chain using the third mark and see if it lines up good.