Mazda Repair Questions? Ask Mechanics for Answers ASAP
What year, model, and engine are you working on? I'll see if I can get you back on track. The chain is completely removed, or just removed from the cam gear?
Ok. I can get you some diagrams on how to put it back together, but this engine is a real bear to get the timing right on.
Mazda lists some very specific tools that are needed and a number of mechanics on the repair forums insist that it is absolutely necessary to use those tools.
To get the crank in TDC initially you will have to rotate it a little, then rotate the cams a little then rotate the crank a little and so forth until you get everything close. You won't be able to just turn the crank without it interfering with the valves unless you have pulled both of the cams.
From there you should be able to follow the repair diagram.
Here is a TSB from Mazda on how to get it set correctly. Mazda put it out because so many technicians were struggling with it.
Everything you need to know is in that bulletin. I'll opt out.
By the way, it doesn't matter how the sprocket goes on the end of the camshaft as long as it doesn't create slack between the two cam gears.
Tech Tip from Mazda: If the cam was not indexed before sprocket removal, the sprocket can go on in any position and still function properly. The important thing is to make sure that it doesn't get installed in a manner that would create any slack in the timing chain in between the two cam gears. Other than that, it doesn't matter how it is positioned on the end of the camshaft.