P80 (-1998 , 1999-2000) Serpentine belt path route diagram picture

Post by **abscate** » 26 Nov 2017, 05:13

: image.jpg (182.08 KiB) Viewed 16975 times

Post by **erikv11** » 26 Nov 2017, 08:44

Go to IPD's pages when you can't recall how to route the serp belt.

: IPD serp belt P80 https://www.ipdusa.com/products/8483/115286-auxiliary-serpentine-drive-belt-for-models-without-air-conditioning-850-s70-v70-c70; fullsize_6592.jpg (66.8 KiB) Viewed 16956 times

Post by **abscate** » 26 Nov 2017, 08:53

Do you see the problem with the 1999- short belt routing? The alternator reverses direction of rotation so that a free wheeling pulley will no longer make juice. You could get home during daylight from an hour or two and a good battery

The Zexel AC compressor also mounts differently than pictured. 4 Long M10 x 150? Bolts run front to back into four mounts on engine vs the transverse bolts pictured above

Post by **scot850** » 26 Nov 2017, 09:09

I am not seeing what you are. The belt is turning the alternator in the same direction in both pictures. There is just less contact surface on the alternator pulley, which is why Volvo changed the belt routing at one point.

Neil.

Post by **bmdubya1198** » 26 Nov 2017, 11:24

scot850 wrote: 26 Nov 2017, 09:09 I am not seeing what you are. The belt is turning the alternator in the same direction in both pictures. There is just less contact surface on the alternator pulley, which is why Volvo changed the belt routing at one point.

Neil.

That is the -'98 short belt routing in Erik's picture. The '99+ uses a different belt and routing.

Post by **scot850** » 26 Nov 2017, 12:05

I am looking at the top picture that abscate shows as a 99- routing. It would work the same as that for the 98, or is the picture wrong?

Neil.

Post by **abscate** » 26 Nov 2017, 12:10

We don’t have a picture of the 1999 with a short belt but if you look at the right hand picture of First post a short belt runs from bottom of crank pulley to to bottom of alternator , which reverses its spin

1998v70xcbill · Post by **1998v70xcbill** » 26 Nov 2017, 15:00

I'm no expert, bu I googled it and found
"An alternator will charge spinning backward. ... Since the fans are centrifugal, they work, but less efficiently in the backward direction" . The brushes should be ok going backwards too. Might be ok short term.

Post by **abscate** » 26 Nov 2017, 17:22

Electrically you are fine but if you have a freewheeling pulley the alternator won’t charge. It’s a mechanical issue.

The other issue is the rotation is now unscrewing the pulley from the hub, which can get interesting.

Post by **bmdubya1198** » 26 Nov 2017, 17:26

1998v70xcbill wrote: 26 Nov 2017, 15:00 I'm no expert, bu I googled it and found
"An alternator will charge spinning backward. ... Since the fans are centrifugal, they work, but less efficiently in the backward direction" . The brushes should be ok going backwards too. Might be ok short term.

Well, the obvious way to check this theory would be to test battery voltage at idle. If it's charging, I see no reason to worry about it other than the fan not working as efficiently as possible.