cataway
02-07-2009, 08:02 AM
this is not about how to put in cams ,its about what to look out for before the install .
on the ltz /kfx exhaust cam there is a rivet that the decompresser
pivots on , in the manufacturing of the cam some times the rivet is not peened over as much as it should of been and it may strike
on the casting next to the journal.
the best thing to do would be to return it for a replacement cam,
next best thing is to grind just enough of the rivet so that it clears ,and can spin freely. do not grind the rivet off flush ,it does need some rivet sticking out to keep the rivet from walking out .
after the install and before you start the engine ,turn the engine through a complete cycle ,of 4 rotations of the crank. if there is no contact of the rivet to the casting then your good to go.
this is what to much rivet looks like.
http://i44.photobucket.com/albums/f9/cataway/OldPictures176.jpg
this is what can happen if the rivet sticks out to far.
http://i44.photobucket.com/albums/f9/cataway/OldPictures173.jpg
you my note ,the rivet striking as it did had to of put a good deal of stress on the valve train which as well will make a very audible
knock/tick noise coming from the head area.
there are other ticks and clicks in the head area so please do not confuse this problem with the normal noises .
on the ltz /kfx exhaust cam there is a rivet that the decompresser
pivots on , in the manufacturing of the cam some times the rivet is not peened over as much as it should of been and it may strike
on the casting next to the journal.
the best thing to do would be to return it for a replacement cam,
next best thing is to grind just enough of the rivet so that it clears ,and can spin freely. do not grind the rivet off flush ,it does need some rivet sticking out to keep the rivet from walking out .
after the install and before you start the engine ,turn the engine through a complete cycle ,of 4 rotations of the crank. if there is no contact of the rivet to the casting then your good to go.
this is what to much rivet looks like.
http://i44.photobucket.com/albums/f9/cataway/OldPictures176.jpg
this is what can happen if the rivet sticks out to far.
http://i44.photobucket.com/albums/f9/cataway/OldPictures173.jpg
you my note ,the rivet striking as it did had to of put a good deal of stress on the valve train which as well will make a very audible
knock/tick noise coming from the head area.
there are other ticks and clicks in the head area so please do not confuse this problem with the normal noises .