Timing Marks On 2002 Chevy Astro

[wmako]

I am trying to install a distributor in a 2002 Chevy Astro Van 4.3L Vortec. I am finding two lines (timing markings?) on the balancer, about 90 degrees apart, and am not sure which of these to use. I also do not see anything obvious to line them up with. Any help is greatly appreciated. Thanks.

[Jsdirt]

Remove the spark plug from the #1 cylinder (driver's side front of engine). Put a cheater bar & socket on the center nut of the crank pulley to turn the motor over. Pick one of the lines, then stick a metal coathanger thru the plug hole & see how far in it goes (angle it downward slightly). Then try it again on the next mark. When the hanger barely goes in, that's the mark you want.

 

If it were me I'd also remove the valve cover just to verify COMPRESSION stroke vs. OVERLAP.

 

As long as your at top dead center compression on #1, and the rotor is facing the #1 contact on the cap, it won't matter what mark is where ... although I would mark it's location then for future reference.

[KENNHON]

Remove the spark plug from the #1 cylinder (driver's side front of engine). Put a cheater bar & socket on the center nut of the crank pulley to turn the motor over. Pick one of the lines, then stick a metal coathanger thru the plug hole & see how far in it goes (angle it downward slightly). Then try it again on the next mark. When the hanger barely goes in, that's the mark you want.

 

If it were me I'd also remove the valve cover just to verify COMPRESSION stroke vs. OVERLAP.

 

As long as your at top dead center compression on #1, and the rotor is facing the #1 contact on the cap, it won't matter what mark is where ... although I would mark it's location then for future reference.

 

I did EXACTLY that with my '96 7.4L duallie..... including taking off valve cover..... then turning engine to line up #1 plug and marks on balancer. installed new distributor with ROTOR facing #1[with distributor FULLY seated!] guess what? it started--- BUT it threw P-1345 immediately---sometimes it backfires.... sometimes[with timing light hooked up] it shows intermittent firing. so it took off the coil appendage---took it to Advanced Auto to test both coil AND 'timing module'... BOTH were fine.....

 

BTW: when it starts, it will NOT increase RPM no matter what i do with throttle!!! and IF i don't press down at least an inch on gas pedal... it won't start... and it won't keep running if i don't keep throttle open that much!!!

 

I'm stuck! Chevy dealer is almost 20 miles away! BUT if that is only way---what the 'Hay'??? any help WOULD be worth at least one free beer![as in a CASE!!!]

[minibike132]

Remove the spark plug from the #1 cylinder (driver's side front of engine). Put a cheater bar & socket on the center nut of the crank pulley to turn the motor over. Pick one of the lines, then stick a metal coathanger thru the plug hole & see how far in it goes (angle it downward slightly). Then try it again on the next mark. When the hanger barely goes in, that's the mark you want.

 

If it were me I'd also remove the valve cover just to verify COMPRESSION stroke vs. OVERLAP.

 

As long as your at top dead center compression on #1, and the rotor is facing the #1 contact on the cap, it won't matter what mark is where ... although I would mark it's location then for future reference.

 

I did EXACTLY that with my '96 7.4L duallie..... including taking off valve cover..... then turning engine to line up #1 plug and marks on balancer. installed new distributor with ROTOR facing #1[with distributor FULLY seated!] guess what? it started--- BUT it threw P-1345 immediately---sometimes it backfires.... sometimes[with timing light hooked up] it shows intermittent firing. so it took off the coil appendage---took it to Advanced Auto to test both coil AND 'timing module'... BOTH were fine.....

 

BTW: when it starts, it will NOT increase RPM no matter what i do with throttle!!! and IF i don't press down at least an inch on gas pedal... it won't start... and it won't keep running if i don't keep throttle open that much!!!

 

I'm stuck! Chevy dealer is almost 20 miles away! BUT if that is only way---what the 'Hay'??? any help WOULD be worth at least one free beer![as in a CASE!!!]

 

 

You are 1 tooth off! Where do I pick up my beer