fishhead Posted February 12, 2007 Share Posted February 12, 2007 Hi I was lining up the timing marks on the crankshaft to prepare to change the timing belt. I was using a socket and breaker bar to turn the crank bolt clockwise. I went about 1 degree past TDC, so I turned the crankshaft back just the tiniest little bit. Something went "BOING" in the area of the driver side camshaft. Then when I was loosening the cam pulley bolt it was turning a bit either way as I struggled to break it loose, it was at TDC, and again I heard that "BOING" sound. Like if you take a little metal ruler and hold it on the edge of a desk and "twang" it. So - what is that?? Any ideas? thanks FishHead ej22e 96 legacy ob Quote Link to comment Share on other sites More sharing options...
idosubaru Posted February 12, 2007 Share Posted February 12, 2007 it made this with or without the belt installed? the cam shafts are spring loaded by the lifters and cam lobes, so the forces cause lumpy turning and snapping movements at certain points in their rotation. is it more than that? Quote Link to comment Share on other sites More sharing options...
fishhead Posted February 12, 2007 Author Share Posted February 12, 2007 it made this with or without the belt installed? the cam shafts are spring loaded by the lifters and cam lobes, so the forces cause lumpy turning and snapping movements at certain points in their rotation. is it more than that? GroosGary, Thank you for the reply. The T belt was and is still installed. It is not the variation in resistance while turning. I know what you mean and that is not it. It is an actual boing sound. I have not had an engine apart in about ten years - but do you think it could be a sticking valve that sort of "lets go" - gets unstuck, and snaps down when I back off the cam? I'm really guessing here. thanks again, FishHead Quote Link to comment Share on other sites More sharing options...
cookie Posted February 13, 2007 Share Posted February 13, 2007 Very possible. Quote Link to comment Share on other sites More sharing options...
Snowman Posted February 13, 2007 Share Posted February 13, 2007 It's the spring "boinging" as it quickly releases its pressure. Nothing to worry about. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 13, 2007 Share Posted February 13, 2007 on the other hand, boing follwed by ching ching ching is bad.... :-p nipper Quote Link to comment Share on other sites More sharing options...
weddes05 Posted February 15, 2007 Share Posted February 15, 2007 At TDC on a dual cam both the intake and exhaust are sitting close to the top of a cam lobe so they are going to be the ones that will want to snap away at TDC. The pass side will turn back and forth freely at TDC. Quote Link to comment Share on other sites More sharing options...
fishhead Posted February 15, 2007 Author Share Posted February 15, 2007 At TDC on a dual cam both the intake and exhaust are sitting close to the top of a cam lobe so they are going to be the ones that will want to snap away at TDC. The pass side will turn back and forth freely at TDC. Thank you for that good information. I can visualize what is happening now. Now that I have the belt off, I found the cams to behave exactly as you describe. Fishhead Quote Link to comment Share on other sites More sharing options...
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