M110 Valve Niose

[jpp]

WHY IS IT THAT WHEN I SET THE VALVE CLEARANCES ON MY 1979 280S W116 TO THE SPECIFICATIONS THE STILL CLATTER, THIS CANNOT BE WEAR AND TEAR AS THE CAR HAS DONE ONLY 93000KM AND WAS LIKE THAT FROM NEW.ALL MY M110 ENGINE CARS HAD THIS PROBLEM, IN THE 280SE W126 IT IS LESS NOTICEABLE, MAYBE BECAUSE THE CAR HAS BETTER SOUND MATERIAL THAN THE W116, BUT IF YOU OPEN THE HOOD ITS THERE, ITS ALWAYS THERE! EVEN IF YOU ADJUST IT VERY CAREFULLY ITS THERE, THE VALVE CLATTER

WHAT CAN BE DONE TO REMEDY THIS?

CAN ONE TAKE THE CLEARANCES DOWN TO 0.20 MM EXHAUST AND 0.05MM INLET? WHAT IS THE CAUSE OF THIS NOISE?

I HAVE ADJUSTED THE EXHUAST VALVES AT 0.20MM AND ITS A LOT BETTER NOW BUT STILL PRESENT, CAN I TAKE THE INLET DOWN TO 0.05MM?

[jpp]

AFTER READING NHDOC'S WRITE UP ON W108 HEAT, I HAVE COME TO THE CONCLUSION THAT I FEEL THE SAME OVER M110 VALVE ADJUSTMENT

[280Sbenz]

the clatter as you call it is quite normal if you adjust your valve clearances down this can result in excess heat on the valve faces causing premature wear!

maybe try using a different brand of oil ?

make sure you adjust your valves on a cold engine its easier and saves burning your hands

0.25mm exhaust and 0.10mm inlet

adjustable valves do this

[t walgamuth]

i agree. they are mechanical lifters. no way to avoid some noise.

the newer benzes have hydraulicly adjustable lifters so are a lot quieter, but the tradeoff is that they need replacing more often. and sometimes stick and tick louder than your mechanical ones.

also the germans used to think hearing your motor was not VEROBTEN unlike here in the us where hearing motors is only acceptable in certain oddball circles (like here amongst the car and diesel nerds),

tom w

[jpp]

Thanx Guys, Just As Long As I Know The Niose Is Normal, I Will Live With It, Btw 280s I Have Found The Dual Pipe Set Up You Refered To In Your E Mail Of A 280e W123, And I Am Going To Install The Manifolds With The Two Seperate Header Pipes Tonight, And I Cant Wait To Drive Without Any Exhuast Leaks:d

[jpp]

HOWCOME THE EXHAUST VALVE CLEARANCE IS ALWAYS LARGER THAN THE INTAKE VALVES?

[t walgamuth]

because with the heat they expand more.

on the intake the gasses flowing around the valve is cool. on the exhaust it is pretty hot!

tom w

[kitchenrat]

my 74 280 has 92000 miles and noisy valves. i just received a new set of rocker shaft spring clips (110 055 11 93) and will install next week. will let you know if it works. the clips are there to remove the slack by holding the rocker against the cam.

[t walgamuth]

i thought they held the rocker on the ball stud.

tom w

[Tomguy]

They do two things: Hold the rocker on the ball stud and hold the rocker against the valve - although probably even at idle RPMs it doesnt do much of the latter holding due to how weak they are. New spring clips wont reduce valvetrain noise at all.

[duxthe1]

There are a few old world techs out there that will adjust the valves on that noisy beast with the engine hot. Those are usually the quietest ones out there. Though I doubt a quiet one with tight clearances will tolerate near as much abuse as a noisy clattering one.