69roadrunner

Hi, I need to know how hard it is to replace a timing chain tensioner on the drivers side of my E420. I thought it was a sticky lifter and found the noise to be on the front drivers side of the engine around the air conditioning compressor. What needs to be removed? Do I need any special tools? Any help will be greatly appreciated. Thanx, Diane

Ausmbtech

The chain tensioner is on the opposite side to the A/C compressor. Better recheck where the noise is coming from.

69roadrunner

Hi, I have the four cam setup not the twin cams. I'm new to mercedes and do not know the engine size or number at this time (119?). I'm told it has two chains and two tensioners.

sosh

Think you better get some professional help before you try to tackle this one. You can do lots of damage. The noise is likely to be something else.

69roadrunner

Yep I have called several places and can't get a straight answer on the pricing to do dianostics on it. I work on old muscle cars and do not know much about imports. Anyone in Colorado know of a mercedes mechanic I can trust here? I would rather have someone else fix it. I have six other cars so I do not need it. I just like it, it drives nice. It just has a pesky ticking noise that will not go away. I'm possitive the noise is in the front of the motor not in the heads. I took off the serpentine belt to make sure it was nothing else on the engine. With a stethascope you can hear the location of the ticking. Does this engine with four cams have two chains? Thanx for any info

salvine

4 cams and 1 chain. Tensioner is down on the r/s of motor by alt and air pump. Is the noise constant or only at start up? It may be possible to have some carbon that came loose and is bouncing around in a cyl as well. I fixed several of these 119 V-8's with GM's top engine cleaner. Don't think I would rec using this product unless you are familiar with it though. Sorry. I'm in Washington or I would take a look at it for you.

69roadrunner

Hi, Thanx for the info. I flushed the motor several times when I thought it was a sticky lifter with BG stuff. I did it three times. That was pricey. My engine is pretty clean and quiet except for this tapping. It is a constant noise. Sounds like the chain is slapping on the bottom of the drivers front of the engine, like the adjuster is not doing it's job.

Gullwing

Yes four cam with one double row timing chain.
The tensioner is on the passenger side. You should just be able to unscrew it once the alternator is removed. It comes out easy and is one or two pieces, putting it back in might be a little difficult. If it is the tensioner then the niose would be on that side.
Wonder if a timing chain guide rail that is broken?