View single post by Esprit2
 Posted: 01-09-2008 10:45 pm
PM Quote Reply Full Topic
Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 572
Status: 
Offline
Gary,
 
Some pulleys have multiple sets of timing dots on them,  others have just one set.   A set being and IN mark on one side, and an EX mark on the other side.   On pulleys with just one set of marks,  it's easy.
 
The IN mark should face forward on the INtake pulley.
The EX mark should face forward on the EXhaust pulley.
Always time the cams by the marks on the forward face of the pulleys.
 
With the crank accurately indexed at TDC,  align the timing dots or scribed lines with one another on the imaginary centerline between the shafts.   It's not enough to just align the marks.   They could both be high or both be low and still align.   They must align on the centerline to be correct.

The timing marks can be a little bit off the centerline... a portion of a tooth pitch.   That small error is the result of production tolerances or skimming the head.   But you can only change timing/ screw-up in whole-tooth increments (ie, move the pulley one tooth on the belt), and being off by a whole tooth is not right.   Fix it.
 
Regards,
Tim Engel

Last edited on 01-10-2008 08:04 pm by Esprit2