Mercedes-Benz Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
1,112 Posts
Discussion Starter #1 (Edited)
Ok, first sound is from the belts behind the radiator. I don't know what is causing that. The belts appear to be in good shape and they look like they are in track. The sound near then end is coming from the engine on the left side (drivers).



Also, when I rev from 1200-2000rpm i hear some grinding or coarse sound from the engine. Currently I have 152k on it. Should I get the engine opened up and replace pistons, valves, etc if needed?
 

·
Premium Member
Joined
·
16,761 Posts
Probably all the sounds are related to the belt system. Either the belt tensioner and or the idler pulley are bad, or the power steering pump is on its' way out. No need to have the engine torn apart. It's all outside the engine.
 

·
Registered
Joined
·
1,112 Posts
Discussion Starter #3
Probably all the sounds are related to the belt system. Either the belt tensioner and or the idler pulley are bad, or the power steering pump is on its' way out. No need to have the engine torn apart. It's all outside the engine.
i know its not the PS pump cause i replaced it a few months ago, thanks for the input
 

·
Registered
Joined
·
902 Posts
Probably all the sounds are related to the belt system. Either the belt tensioner and or the idler pulley are bad, or the power steering pump is on its' way out. No need to have the engine torn apart. It's all outside the engine.
I agree I would proceed with replacing the Belt, Idler and tensioner in that order all are DIY. Start with the belt and idler and see if the noise is gone first...

I replaced mine with Gatorback belt from Autozone 4 mnths bk has been good so far. Idler from the dealer cheaper than online.thx
 

·
Registered
Joined
·
235 Posts
Ok, first sound is from the belts behind the radiator. I don't know what is causing that. The belts appear to be in good shape and they look like they are in track. The sound near then end is coming from the engine on the left side (drivers).



Also, when I rev from 1200-2000rpm i hear some grinding or coarse sound from the engine. Currently I have 152k on it. Should I get the engine opened up and replace pistons, valves, etc if needed?
Being you have a 99 I would look real good at the harmonic balancer. It could be failing and moved back into the oil pan. That may be the grinding sound you hear. Common problem on earlier ML's. :cool:
 

·
Registered
Joined
·
1,562 Posts
IMHO, it should be very easy (5 minute job) to diagnose which part is making noise. Slip the belt off by turning the belt tensioner counter-clock-wise. Once the belt is off, spin the idler pulley and listen/feel for the worn bearing on the idlery pulley. Similarly, spin the belt tensioner and listen/feel for the worn bearing on the tensioner pulley. I have replaced both the idler pulley as well as the belt tensioner recently.

While the belt is off, you might as well spin the fan (water pump is attached to it) and see if there is a "play" in the water pump pulley.
 
1 - 6 of 6 Posts
Top