[Guest]

Got a question for you about your great ducatitech site -

In your piece on replacing the belts, it says to line up all of the pulley marks, then says once the marks are all lined up, it is at TDC for the ******** cylinder.

What is "*******"??? Horizontal or vertical?

Also, when replacing belts, is it necessary/a good idea to replace the tensioner bearings (or any of the other bearings?). I know on certain cars with belts, replacing the tensioner/idler bearings while doing a belt change is SOP.

Thanks!

 

[chris]

I recall it's the vertical cylinder at TDC. But this doesn't matter. There's a dot on the drive pulley that lines up with the engine case. (This is the pulley in the Vee of the engine) What the cylinders are doing does not matter when timing the cams, you look at the dots and marks.

You check the bearings, yes. They don't often get changed. The tensioner uses two 6201 sealed bearings stacked, while the idler pulley is a special one-off OEM'd to Ducati by SKF.

 

[dj]

What helps me is a little bit of red or yellow nail polish on the timing marks.

-dj

 

[Guest]

Thanks - I know TDC wouldn't really matter for the belts, but I also wanted to check valve clearance, too.

 

[Guest]

With the belt timing marks lined up the Horizontal cylinder is at TDC. The vertical pulley is under closing spring pressure as you'll find out when you remove the belt. I used 1/8" rod, bent like large staple that engages two opposing holes in the pulley to make it easier to rotate the pulley to reinstall the belt. But then I'm old and weak. ;D

 

[chris]

COOL! there's the answer. I remember that now about the top cam being under spring. Man, some of this stuff I really don't pay attention to. I've got a rhythm I get in to and don't really think "outside the box" when it comes to certain processes.

 

[Mark1305]

I remember learning about the upper cam being under spring pressure when I changed my belts - It stayed put when I took the belts off. But when I was putting the new belt on, it decided to turn and get out from under the spring load. Unfortunately, my fingertip was between the belt and the pulley and got rotated about 90 degrees. OUCH