Alternator belt problem

[russ bethel]

I am having problems with alternator belts on my 78 Glenbrook. I thought
the alternator was dragging and caused the first belt to come off. I put a
new alternator (80 amp) on and a new belt. I got about 200 miles and it was
thrown off. The alignment of the belt seems to be fine. I put on a new
alternator belt and a new power steering belt. It seems that I have to put
an extreme amount of tension on the alternator belt to keep it from
slipping. My question is would it be advisable to put a double pulley on
the alternator and run 2 alternator belts instead of the 1 alternator belt
and 1 power steering belt. It seems that it should work but surly someone
has had some experience with this problem and found a solution. I don't
want to go to the serpentine belt route.

Russ Bethel
1976 Glenbrook

 

[thomas g. warner]

First you do not need 2 alternator belts for an 80 amp alternator.

I do not have the technical documents for the 1978 but assume that you have
the 403 engine. I do not have the alternator configuration, but if you have
the technical manuals check to see if you have all of the brackets installed
on the alternator. You need all of the brackets on the alternaltor to keep
it from flexing under load.

If you have indeed checked the alignment of the pulleys and made absolutely
sure that they are in the same plane than there are several other possibilities:

1. Someone has installed the incorrect pully on the alternator, ie; the
pully has the wrong cross sectional design for the belt and the belt is
riding to high on the pully, ie the belt does not make full contact with the
pully.

2. You have the incorrect belt on the alternator, which causes it to not
fully contact the pully. Check it by turning the belt inside out and
putting it in the pully to see if it is making full contact.

>I am having problems with alternator belts on my 78 Glenbrook. I thought
>the alternator was dragging and caused the first belt to come off. I put a
>new alternator (80 amp) on and a new belt. I got about 200 miles and it was
>thrown off. The alignment of the belt seems to be fine. I put on a new
>alternator belt and a new power steering belt. It seems that I have to put
>an extreme amount of tension on the alternator belt to keep it from
>slipping. My question is would it be advisable to put a double pulley on
>the alternator and run 2 alternator belts instead of the 1 alternator belt
>and 1 power steering belt. It seems that it should work but surly someone
>has had some experience with this problem and found a solution. I don't
>want to go to the serpentine belt route.
>
>Russ Bethel
>1976 Glenbrook
>
>
>

 

[john szalay]

>I am having problems with alternator belts on my 78 Glenbrook.
>thrown off. The alignment of the belt seems to be fine. I put on a new
>alternator belt and a new power steering belt. It seems that I have to put
>an extreme amount of tension on the alternator belt to keep it from
>slipping. My question is would it be advisable to put a double pulley on
>the alternator and run 2 alternator belts instead of the 1 alternator belt
>and 1 power steering belt.
>
>
If the belts are fairly new and/or not glazed , and the alignment is
correct, then look for worn pulleys. The inner walls of the pulleys do wear
and can cause
the types of problems you have.

The double pulley route can solve that problem BUT.....

One problem with putting dual belts, is it requires you to purchase a matched
set of belts. dispite the "sizing", its rare to find a pair of V-belts exactly
the same length. unless you get a matched set, but they are available from
supply houses. We go though this at work all the time. We normaly call our
supplier to special order matched sets when needed.