The crank shaft timing gear and the camshaft timing gears have marks on them. These marks are lined up so the crank gear is on top and the cam gear is on the bottom. when a straight edge when placed through the center line of the crankshaft and camshaft and lined up with the marks on the gears, the timing is correct. this is the procedure that I found in a old maintenance book for the GMC 305 V6 engine. I found that when you line up the timing marks this way that you are actually 180 degrees out ( number one is on the exhaust stroke) so your distributor will be pointing at cylinder #4. roll the engine around 180 degrees from this point( if looking at the timing chain the cam mark will be on top and the crank mark will be on top and they will both line up with a straight edge through the center-line of both shafts) and make sure that the distributor is actually pointing at number one. I do not know why the book does not have you line up the timing marks so you are on top dead center compression but it is easier to line them up the way the book says.
what do you mean by change there is only one position for the timing mark and that t.d.c. top dead center
You need a timing light, hooked to the #1 spark plug, pointed at the timing mark on the main pulley on the front of the engine.
No, a 95 GMC Sonoma does not use a timing belt on it. The 95 GMC Sonoma uses a timing chain on it.
no timing belt on a GMC Jimmy
what is the timing degree for a 1966 gmc 292v6
Where is the timing connector on a 1995 gmc sonoma
You must make sure you have the distributer mark aligned with mark on the intake manifold. The PCM makes all the timing adjustments. Info: The distributor is only used for the cam position, and spark distrubition.
how do you set timing on a 1985 350 gmc truck
Engine 4.3L (262 cid)Base Timing 0~ TDC (Manual Trans).Engine 4.3L (262 cid)Base Timing 0~ TDC (Auto Trans).
how do i set the timing on a 81 gmc 250 inline 6 cyclinder ?