How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Marty Your Own Question
Marty, Mercedes Technician
Category: Mercedes
Satisfied Customers: 54028
Experience:  Bosch Certified Master Tech. Over 35 years experience.
Type Your Mercedes Question Here...
Marty is online now
A new question is answered every 9 seconds

1995 s500: tapping noise..valve covers to check oil tubes, all..loose

Resolved Question:

I have a 1995 s500 . has tapping noise, worse when warm. we have removed valve covers to check oil tubes, all in place but seem loose. can oil bleed by if loose ? thanks dave
Submitted: 8 years ago.
Category: Mercedes
Expert:  Marty replied 8 years ago.

Hi Dave, if the o-rings are in place I wouldn't expect some movement in the tube to be your problem. It sounds like you're aware of what goes wrong with the tubes already but just to be sure I've attached a picture. Check them carefully, if they're all good your problem may be with a cam or lifter itself. I assume your tapping is at valve speed, not piston speed.






Marty and 2 other Mercedes Specialists are ready to help you
Customer: replied 8 years ago.
the cam lobes look good, the only concern i have is the noise sounds like a complete bank is noisy, not just 1. our oil pressure seems at high end of specs, can too high oil pressure bleed oil by tubes. we haven removed all yet,but the ones we have removed the o ring is there,but the new tubes fit tight.
Expert:  Marty replied 8 years ago.
I can't imagine the looseness being a problem. Are the fittings on the quiet side just as loose? If it's a complete bank, especially the right bank, I'd make sure my cam timing was correct. Has anyone replaced a chain tensioner or something like that?
Customer: replied 8 years ago.
tech says noise may be louder on right bank. first time we have seen vehicle, vehicle only has 71k. do not see any signs engine was repaired, customer not owned very long. but did run hot and was towed in, we replaced themostat to correct that problem. seemed ok except oil level light comes on, tested to be bad sensor. we are trying to correct noise problem before dealing with level light.
Expert:  Marty replied 8 years ago.

Ok, if you have good oil pressure you might go ahead and try the new bridges but I think I'd warn the customer that it may not solve the problem. I'd also change the oil with 20W50.