I am a new 2000 S500 owner and the dealership is having a problem fixing a lifter. The engine is very clean (well maintained) and the oil pressure is fine. The problem is everytime they replace this one lifter and other parts (rockers, bolts, etc) after a test drive the tapping problem reoccurs. Their techs are at a lost. What can be causing this problem?

Thanks...


P.S. The car has been in the shop for a week.

 

Worn Cam shaft lobe.

 

Exactly, worn camshaft lobe.

Oil hole plugged near that lifter?

 

Is the Cam Shaft Lobe expensive to repair? What is the estimated cost?


Thanks...

 

Yes...kind of expensive...that camshaft must be replaced. Is this a high mileage car? Camshafts are ground from very hard material but do wear down...reason...lack of lubrication. This would be very disturbing to discover on a Mercedes. Have your mechanic check the lift and duration of the valve opening with a dial caliper set up to see if it is within spec. If not, the cam is bad. If it is then that lifter/cam follower or some of it's related hardware may be defective or wrong parts. Other than that...you might have a lubrication issue such as a restriction in an oil gallery. Good luck. My guess is the lifter is collapsing because of dirt or grit inside preventing oil from moving through it. Just a guess.

 

I purchased the car with 63k; now it has 65K. It is desert silver w/great acceleration. I had a 2000 s430 previously, but it was very slow. After reading the posts on this board, I decided to purchase a S500. I upgraded the S430 with the CL grill, tail lights, and quad tips. The dealer gave me a straight trade. I only had to pay (out of pocket) tax and tags. Unfortunately, this is not a CPO and I could not at the time afford an extended warranty.

The mechanics at the Mercedes dealership, I assume, have check the camshaft, camshaft lobe, and oil opening. I might be assuming too much, since it is a dealership. It has been at the dealership for a week and three days. The service manager said the engine is in very good shape, and was well maintained. I have the service record and CARFAX, and did not see any major abnormalities.

BTW, I spoke to an independent mechanic and he said to fix the lobe could cost around 3k; the timing belt, camshaft pulley, and other items will need to be disassembled. I very big job. I really like this car!! It is bone stock and is going to stay that way

 

I thought about this one a bit. I keep coming back to this question...are you certain that the tapping is caused by a lifter..or that particular lifter? These noises can be difficult to diagnose.

Another thought is the competence of the individuals working on your car. Don't say anything to the dealer but snoop around a little and see if you can talk to others who have had there cars serviced there. Call MBUSA tech service and discuss the problem with them. There might be a service bulletin on this issue...you never know untill you ask. That shop knows that you are paying out of pocket for this work and that there will be a limit. That might also be limiting their "activity". Ask around town about reputable independent Mercedes mechanics. Their rates will be lower and their knowledge may be deeper.

It is scary to have major problems with a high end car without warranty coverage. This thing is probably going to end up being something simple...keep your eyes open.

 

Sprink49, I got rid of the S500. The final outcome was a cylinder head replacement. Lesson learned: never purchase an expensive car like this without a warranty. BTW, I traded for a 2003 E320 CPO. It doesn't have a Navi; however, I will purchase an after market unit that can take voice commands - no big deal.

I looked at a 2005 ML500, but was not enthusiastic about the V8 gas guzzler. Also, the outdated body bothers me. Anyway, thanks for your input. Good stuff!!!