Mark Hart
Active Member
- Joined
- Apr 26, 2019
- Messages
- 25
- Reaction score
- 5
- Location
- North East England
- Your Mercedes
- Mercedes-Benz C209 CLK500
Hi guys,
Looking for some advise on where to start looking for an unusual noise coming from the front of the engine.
My car is a 2004 CLK500.
Background to this is about 6 months ago I did an overhaul of the cooling system as preventive maintenance (since the previous owner didn’t seem to prevent much), this included:
New thermostat
New water pump
New tensioner pulley
New idler pulley
New alternator voltage regulator (why not whilst in the area)
New auxiliary drive belt
Full new set off radiator hoses and clamps
New coolant.
I also tried topping up the ac whilst having access to the condenser etc but it turns out I have a leak somewhere in the system that’s probably been there a while.
Every time I’ve driven the car there’s a sound that’s nagging me that doesn’t sound right, I honestly can’t remember if it was there before this overhaul or not.
I’ve recorded a video of the sound but it’s too large to upload here. Essentially when the car starts cold there’s a groaning noise that goes off after about 15 seconds, then you can here a high pitched whinging noise that seems to be coming from the area around the alternator. Ironically with alternators sometimes being called generators it sounds like one of those industrial electrical generator they use for lifts etc.
When I took the alternator off the engine to replace the voltage regulator I checked the pulley for play and it felt tight. The old water pump and idler pulley has lots of play so I’m glad I replaced them.
Do you think now with a good water pump, pulleys and new belt that maybe there’s too much tension on one of the driven components like the alternator that could be causing this noise?
The other thing I’ve noticed is when driving you can hear a clicking/ticking noise from the front of the car very faintly when between 750-2000 rpm, it sounds like the aux belt slapping, if you apply a small bit of throttle to 2200rpm the sound goes until you let off the throttle.
Would you guys recommend loosening the aux belt and checking all of the pulleys again?
What would you investigate first?
Looking for some advise on where to start looking for an unusual noise coming from the front of the engine.
My car is a 2004 CLK500.
Background to this is about 6 months ago I did an overhaul of the cooling system as preventive maintenance (since the previous owner didn’t seem to prevent much), this included:
New thermostat
New water pump
New tensioner pulley
New idler pulley
New alternator voltage regulator (why not whilst in the area)
New auxiliary drive belt
Full new set off radiator hoses and clamps
New coolant.
I also tried topping up the ac whilst having access to the condenser etc but it turns out I have a leak somewhere in the system that’s probably been there a while.
Every time I’ve driven the car there’s a sound that’s nagging me that doesn’t sound right, I honestly can’t remember if it was there before this overhaul or not.
I’ve recorded a video of the sound but it’s too large to upload here. Essentially when the car starts cold there’s a groaning noise that goes off after about 15 seconds, then you can here a high pitched whinging noise that seems to be coming from the area around the alternator. Ironically with alternators sometimes being called generators it sounds like one of those industrial electrical generator they use for lifts etc.
When I took the alternator off the engine to replace the voltage regulator I checked the pulley for play and it felt tight. The old water pump and idler pulley has lots of play so I’m glad I replaced them.
Do you think now with a good water pump, pulleys and new belt that maybe there’s too much tension on one of the driven components like the alternator that could be causing this noise?
The other thing I’ve noticed is when driving you can hear a clicking/ticking noise from the front of the car very faintly when between 750-2000 rpm, it sounds like the aux belt slapping, if you apply a small bit of throttle to 2200rpm the sound goes until you let off the throttle.
Would you guys recommend loosening the aux belt and checking all of the pulleys again?
What would you investigate first?