Small block idler pulley

[BergmanAutoCraft]

FWIW....I can't see the overall accessory drive/belt layout on anyone's car that posted on here. But idlers are typically used to increase belt wrap on a driven component. You want the proper amount of wrap to prevent belt squeal or slip. So if youre looking to see if an idler was needed or used, look to see if a component looks to have insufficient belt wrap.

This was a factory thing not an add on.

 

[lemondana]

In the 80s. South Florida, my brothers 70 Duster 340 had AC, manual steering. Very unusual. It was a V groove idler with a bracket bolted to the driver side water pump.

It is bolted on the passenger side. I tried it on the driver side and it just don't work on that side. The layout is that same as big block with AC- 1 short belt on crank pulley, and water pumpp pulley and the idler pulley.It needed a 13371 belt.

 

[BergmanAutoCraft]

I don't think so. It take the place of the power steering pump. The belt goes around the crank/water pump/idler.

 

[lemondana]

I have a picture of one installed years ago. There is not a belt on it, kind of looks like they added PS and just left the idler on it. I went out and installed the one that I have on a water pump both ways. It seems to be a better fit mounted on the passenger side. Here is the picture that was posted on this forum back in 2016. www.forabodiesonly.com/mopar/attachments/dscn0162-1-jpg.1714886145/

 

[lemondana]

You'll have to enter the whole line in.

 

[Demonx2]

This was a factory thing not an add on.

Exactly! So the accessory drive engineer at that time for some reason must have believed he had insufficient wrap on some component and added an idler. He didn't add it just to add cost!

 

[BergmanAutoCraft]

No. Its because ac cars have a pulley arrangement that goes ps/crank/wp. Without the PS, you need something in its place.

 

[70dart340]

My '70 Swinger 340 is a factory A/C car (H51) with standard brakes and steering. It has the pulley like the photo previously posted. I can try to dig mine out for pictures, if needed. And for the naysayers, I have the legible build sheet for the car. Found it under the back seat.

 

[340sFastback]

My '69 340 car is factory AC manual steering manual brakes but about every other extra cost option on fender tag. Sort of an odd ball car. Original owner who I bought it from special ordered it.