2006 xc 90 V8 New alternator new tensoiner belt slipping

VFLXC90 · Post by **VFLXC90** » 08 Nov 2013, 15:20

I just installed a reman Bosch Alternator and a new tensioner/ belt. I started the XC and the belt slips on the pulleys. checked my routing of the belt per the diagram on this site. I pulled of the new belt and installed my old belt. Same issue. I didn't pull the tensioner beyond the 177 foot pound rating. I barley had to put tension on the tensioner to release so I could slip the belt on. I cycled the tensioner a few times thinking I had to pump up the hydraulic plunger. No luck.
I will measure the pulley on my old alternator to see if there is an issue there. I already sent the Alt back to the on line supplier . They will have to measure it for me.

Any suggestions? Could it be the new tensioner its a Volvo part.

Edited 1 time - All caps in title - Please see forum rules

Post by **jimmy57** » 08 Nov 2013, 15:44

The belt is likely on wrong. I know several indy and dealer volvo techs and almost all of them has done this once. Look again at this picture and see if you can spot where yours is off:

VFLXC90 · Post by **VFLXC90** » 08 Nov 2013, 19:18

jimmy,
Thanks for the reply.
I checked the diagram, I will re check it on the xc in the morning. I'm 99% sure it's on per the diagram. I have to release the tensioner to slip the belt on. It just doesn't tighten up enough to put tension on the belt after I release the tensioner. Any other ideas?
Thanks VFL

Post by **jimmy57** » 08 Nov 2013, 22:25

You did remove the spring lock from the new tensioner? They come with a retainer over the spring and you can compress it more but it will not extend with that steel retainer in place.

VFLXC90 · Post by **VFLXC90** » 09 Nov 2013, 06:12

Thank You
I didn't remove that.
I thought it was a new design and the metal plate (lock) was part of the new design.
I'll correct later today and repost.

Thanks Again.

VFLXC90 · Post by **VFLXC90** » 09 Nov 2013, 06:16

jimmy,
I will assume I should remove the lock now that its installed on the engine.
I don't want to take the tensioner off ,remove the lock and try an re install? It probably won't go back in place?

Post by **jimmy57** » 09 Nov 2013, 08:16

Yes, the lock comes off once installed on engine and belt fitted. Keep the lock piece as that is a Volvo special tool to hold the tensioner for fitting a new belt.

VFLXC90 · Post by **VFLXC90** » 09 Nov 2013, 18:15

jimmy,
Thanks again

Good news/bad news.
I popped the plate of, tensioner did its job. Belt is now tight.

I Checked the output of the Alt. 14.2 v.
Ran the xc for 10 min. or so. Service urgent light came on/battery light.

Turned the xc off. Started it, no service light/batt. light. Within a minute or two light came back on.
I will check again in the morning with volt meter. My guess it will charge initially then light on, no charging.
I will check the wire to the Alt. but I remember hearing it clip in. I'll wiggle the connector to see if light goes off.

Any idea's .

My guess is, bad Alt.

Post by **jimmy57** » 09 Nov 2013, 21:08

What was the problem when the original alternator quit?
The alternator has a communicating voltage regulator. The engine control module commands the alt about target charging voltage. If the failure of new is the same as the old then you may have a problem with the communication with ECM. Or it is a bad alternator.

VFLXC90 · Post by **VFLXC90** » 10 Nov 2013, 08:11

I did the repairs as a maintenance prevention. The Alt. was working fine. It has 140,000 on it. Thought it was a good idea to change out.
I realized what I did after my last post.
I put in a new battery.
I put the battery in backwards. I touched negative post to the positive,it didn't fit. Power sent through negative side.So I probably fried an diode? I just hope noting else was damaged.
Your thoughts.