Cambelt Eating itself to pieces

[marc]

Nope can do it engine out. Best with a DTI (dial test indicator) aginst the flywheel mating surface of your crank (make sure DTI base has a good footing too) then measure the clearence (movement) from crank pulled forward to crank pushed back basicly. (easier to move crank around with the timing sprocket on and aux front pully on well I reckon lol).

Altho this shouldnt cause your belt to walk!! :-X

[DRFVDR]

have you tried a different belt ?

may be a belt issue

[nismovzr2003]

 We are borg said:

have you tried a different belt ?

may be a belt issue

Yep new belt, no difference.

[DRFVDR]

i would remove every thing and start again,

check that all of the cam/crank gears are inline ( use a straight edge)

check that all of the idlers are square to the block and cam/crank gears ( use straight edge/square)

[Rosssub]

Has it got all new Idlers/Tensioner etc? You can see the belt walk in this pic:

[soopersubaru]

Heads and/or block recently machined? Incorrect line bore alignment of cams too crankshaft centre.

This will/does cause "belt walk"

Or the aluminium bracket that holds the tensioner setup/idlers onto the block maybe loose or damaged alignment wise.

[log1call]

Either something is twisted, like an idler not sitting flat and square (in every plane) against the block..

or the belt is a bad one. Brand new belts, even from reputable manufacturers, can sometimes be defective in that they are tapered from front edge to back edge. It\'s like if the belt was made way wider, until it was a tube.. the tube would be tapered..

Take the new belt and lay it on the kitchen table on it\'s side, so it\'s a big loop.. now crouch down and try to see if the two sides of the loop are standing up at right angles to the table. If they both seem to be leaning in, or out, overall, then the belt will creep.. and you have to make sure it is a nice round hoop of belt or it will deceive you on such a big belt.. On smaller belt it\'s easy to check, on a belt that big you will need to look from several angles to get an overall picture even with care standing all the belt upright as you can.

[log1call]

The best way to check that all the pulleys and idlers are parallel is to stand to the side and move up and down till two pulleys are appearing almost to touch, and there is only a tiny gap apparent between the top of one pulley and the other pulley\'s bottom edge. That thin line between them should be parallel.

Keep moving around viewing any two pulleys at a time, and trying to do each pulley from the side and from above to check it in both planes.