AC V Belt Question - SBC

[ed1948]

Today I took all the belts off to clean the pulleys and belts.
I noticed when the AC is on the V belt vibrates an inch between the pulleys. It felt tight but should I give it more tension? With AC off belt runs smoothly.

 

[clean8485]

Hi Ed. When the clutch is engaged on the A/C compressor when its running, there is a load on the belt, and it will vibrate more so than when the system is off. I'm trying to remember the routing of the A/C belt. Does it go around the water pump pulley? If so, by tightening the belt, you'll be putting more strain on the water pump bearing, causing it to wear more quickly. If the A/C belt is moving 1 inch with the compressor engaged, then I don't think I'd be too worried, as long as the belt isn't contacting anything else, and the A/C system is working normally. It was partially because of concerns like that, that I switched over to a serpentine setup a few years ago.

 

[ed1948]

Thanks
In the past when I had SBC's I tended to undertensioning the belts. I didn't recall seeing the slop on them.

 

[axisg]

great question. I got the AC working on my car last spring and was having real issue with the belt flopping around. I threw a bearing in-line to take up the slack last year and no more noise or flopping around
https://gbodyforum.com/threads/flopping-ac-belt.56365/

 

[ed1948]

Great idea axisg.