GUz33

New to the 350Z forum just got one a week ago.
My belt came off and had to replace them.

Does anyone have the specs of how tight they need to be?

Thanks!

GUz33

btw this is a 2003 350z

02s2000

iTrader: (1)

Tighten the adjuster bolts until you have about 8-9mm of deflection on the smaller A/C belt with 22lbs of pressure and 4-5mm of deflection on the thicker belt. Then tighten the lock bolt torquing them to 26 ft-lb. Turn the engine over a few times to let the belts get uniform tension and recheck the belt tensions. When you are satisfied reinstall the under-tray.

this is from the DIY section. there is a whole write up with pictures.

GUz33

how do measure deflection? sorry im still new to deflection.
because I think I made the belts too tight.. I can smell rubber burning when im at a stop.

optimusprim3

This. Here's also a link so you don't even have to search
https://my350z.com/forum/engine-driv...very-easy.html

iideadeyeii

iTrader: (6)

Tighten until it doens't slip.

Jennifer 2

Guz33, You measure deflection with a simple ruler or tape measure, but you create the deflection by exerting a force on the top run of the belt, (as per the diagram in the link provided by optimusprim and 02s2000).

My neighbor adjusted the larger alt/power steering belt on my car, and he told me that this would be an audience participation event. I was to provide the 22 lb pressure mid span on the belt. He said we didn’t need ‘no stinking belt gage’ and sent me off to calibrate my thumb on the bathroom scale. While I provided a consistent pressure with my thumb, he tightened the adjuster until the belt measured the correct amount, (4.5mm) of deflection. This is the specification for adjusting a belt that has been in service for quite some time.

A new replacement belt will tend to wear into the pulley grooves somewhat, and after a few hundred miles will lose some of its initial tension. This may even cause a few seconds of squealing on a cold start up. Because of this, the deflection measurement for a new belt should be set to a tighter 3.5mm owing to the fact that it will soon ‘wear in’, losing enough tension to end up at the ideal 4.5mm setting.

GUz33

Thanks! worked on it again earlier this morning so far so good. no slips!