74 big block idler pulley with factory air.

[Charlied]

Want to replace idler pulley. Car has two belts. Original pulley about 1.5 inches wide, diameter 4 inches.Ordered “correct “ pulley from Rock Auto diameter right, width 1 inch, would work with single belt. Napa part same.
Any idea who might sell correct one ? Think part # is 3830 162, if I read my part book correctly.
Thanks

 

[pnora]

Want to replace idler pulley. Car has two belts. Original pulley about 1.5 inches wide, diameter 4 inches.Ordered “correct “ pulley from Rock Auto diameter right, width 1 inch, would work with single belt. Napa part same.
Any idea who might sell correct one ? Think part # is 3830 162, if I read my part book correctly.
Thanks

If its the water pump belt tensioner pulley you are talking about it is a single groove.

 

[Charlied]

If its the water pump belt tensioner pulley you are talking about it is a single groove.

Sorry, I wasn’t clear. The pulley keeps tension (downward)on the twin belts that run from the crank up to the A/C compressor, to the alternator and has no grooves. I think the idea was since it is a long run from A/C compressor to alternator to cut down on vibration and belt hop.
My concern is with the pulley slightly narrower,could a belt slide off. Maybe making a mountain out of a molehill here.
What do you think ?
Thanks for listening.

 

[pnora]

This would be your pulley. 1 inch wide is plenty for two belts. 1974 DODGE CORONET 6.6L 400cid V8 Idler Pulley | Shop Now at RockAuto