There is this tapping noise coming from my engine. It is very noticable at
idle. I use Mobile 1 for the oil. The car can be hard to start sometimes
too. I have new plugs, distributer/rotor, wires, air filter, ect. The
plugs seem to get dirty fast, with oil on them. The car doesn't burn any
oil. When warmed up th emotor is a little rough at idle but runs good
when opened up. Any suggestions would be greatly appreciated.-Charles-89
Consider that the fuel injectors may be leaking at shut down due to fuel
deposits and need to be cleaned. A couple of cans of fuel injector
cleaner may cure that. There may even be a carbon build up on the back
of a valve that prevents it from closing fully resulting in the tapping
that you hear. That's the optimistic diagnosis.
The pessimistic diagnosis is that the valve guide seals are worn and are
allowing oil to be sucked into the intake manifold. One valve guide may
be loose in the head causing the tapping that you hear.
If you idle the engine when hot for say 3 to 5 minutes and then rev it
up (in place) does it produce a blue cloud of oil smoke from the
exhaust? If so the valve guide seals are probably worn out and ought to
be replaced. An experienced M-B mechanic can do that job without
removing the engine's cylinder head. However, a loose valve guide may
require the head to be removed.
On 1/17/05 8:50 PM, in article
DonΉt know for a 300e but on my 95 c280 I just had the head gasket replaced
and a top end overhaul. Total cost: $2400 in washington dc (the car has only
70k, and is in excellent condition hence it was worth) at a independent
I just had valve seals replaced on my 1987 300E at an independent
Mercedes Benz shop here in Central California. Including new plugs a
little over $400.00.
Someone earlier posted $400-600.
Pete Cowper (1987 300E)
It could be the bushings are bad on the tensioner shock. Common problem.
Suggestion: buy a cheap stethoscope for about $10 and listen for the source
of the tapping noise before investing in major work.
At 130K, if serviced properly, the guides should still be good. Seals may
need replacing, but that should be evidenced by oil consumption and deposits
on the plugs.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.