Mercedes-Benz Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
393 Posts
Discussion Starter #1
Anyone know how to tighten the A/C Idler belt on the M110? I did a search and could only find info for the diesels. Mine is slipping and making my idle super low and rough sounding. This is on my 280sel, but I figured it would be the same as the 280e's and ce's.
 

·
Registered
Joined
·
6,118 Posts
To tighten the a/c belt do this:

Loosen the allen head bolt on the front of the pulley
Turn the 10MM bolt on the right side of the pulley clockwise until it is tight enough
Tighten the front allen head bolt back down


When did you get a M110
 

·
Registered
Joined
·
6,118 Posts
^^^Got me.
 

·
Registered
Joined
·
393 Posts
Discussion Starter #6
I got the car last fall. I don't know exactly why it lowers the idle, but before it started slipping, it would do about 700 rpm or so in park, but it can barely manage 400-500 now. Also, should you be able to turn the 10mm bolt without loosening the allen head bolt? I couldn't find the right size allen head, so I just tried turning the bolt to see what would happen. It moves freely, but doesn't seem to do anything. BTW, do you know the size of the allen head bolt? Thanks!
 

·
Registered
Joined
·
393 Posts
Discussion Starter #8
the car wont run at 400rpms, and it would be even lower in drive, and even lower in reverse. does it miss at all?
No, its not missing. I know its the belt, because as I watch the engine idling, it will speed up to normal whenever the belt catches, but when it is slipping and the belt isn't moving, the idle goes back down.
 

·
Registered
Joined
·
6,118 Posts
You can turn the 10mm bolt but it will not do anything other than put alot of pressure on the bolt and it may break if the allen bolt isn't loose.
 

·
Registered
Joined
·
1,805 Posts
No, its not missing. I know its the belt, because as I watch the engine idling, it will speed up to normal whenever the belt catches, but when it is slipping and the belt isn't moving, the idle goes back down.
Have you tried removing belt and seeing what car does as far as idle. I am with viper on this don't see connection If anything it should slow down when it catches something else is affecting idle remove belt and see.
 

·
Registered
Joined
·
393 Posts
Discussion Starter #11
I tightened the belt (it's takes a 8mm hex wrench, btw), and its back to normal now!
 
1 - 11 of 11 Posts
Top