4.3 timing

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4.3 timing

Unread post by Guest » Sat Apr 24, 2021 9:54 am

have 2003 astro van intermittent start problem runs great mech said timing gear was installed 180 degrees out marks dont line up said motor was gone yet viecle runs great . Want to get new timing chain installed and fix this so lines up.

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Re: 4.3 timing

Unread post by carriedi » Sat Apr 24, 2021 10:53 pm

not sure what you mean 180 degrees out. the cam gear moves once for every two times of the crank gear. So if you look at the timing marks - one revolution they line up - the next revolution they will be 180 out. Is there a problem? The piston TDC is the same for compression and for exhaust. The cam makes the difference between compression or exhaust.

Tell me about your intermittent start problem. What happens when you have the no start?