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M110 valve adjustment tips?

6069 Views 27 Replies 5 Participants Last post by  nobby
I have read Nobby's valve adjustment writeup and it is my guide.

I have the feeler gauge, the special wrench, the valve cover gasket and the will to do it as an oil change is up.

My question is there anything to look for while the engine is opened up? I want to measure the timing chain stretch, I think you line the engine up to TDC on the crank pulley then you compare the marks on the cam and see how much it is off.

When I turn the motor over is there anything I should do other than

Is there anything to look at? Check the rocker arms or rattle clips for wear?
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I doubt very much you will register any chain stretch. That fucking chain is robust.

I would, however, check for wear on the sprocket teeth and on the rubber lined rails.
Ok I'm going to button the car back up tomorrow. Overall a pretty easy job and I'm glad I did it as most of the valves were pretty tight.

I measured the chain stretch and it is 2* advanced so pretty much dead on. Me so happy. Hopefully the car still runs after I'm done.

Thanks for the help and tips and thanks to Nobby for writing up the procedure.

Anyone know the valve cover torque specification? It felt like it was one pretty loosely so it must not have to be too tight.
1 from the center...out.
Loud = Good
Quiet = Bad

The higher idle might be attributed to you dislodging a vac line or something else whilst performing the valve adjustment.
..............but you will get the most accurate adjustment with a COLD engine. Overnight cold.
I have a doubt for some time on...

Allways when I adjusted my M110 valves I read on the manual intake 0,10 mm and exahust 0,25 mm (Cold Engine) and now my fouvorite part warm engine (60º Celsius) intake 0,15 mm and exahust 0,25 mm.

So...hotter engine more valve clearence ? inst supoused to expand and bring the valve lash tighter when the engine warms up ?

So why give some clearence at first if when it warms up It will make his "own" clearence ? Why not give 0,10 on both sides ? I cant understand this manual.

Can someone give me a reasonable explanation for this ???

Tnks !!!
I'm surethere must be an explanation ....but the best way to adjust is still on a cold engine.
Yes, I know. I allways did my valves whit an overnight cold engine.
I was just curious about the gaps being larger whit a warm engine.

Another thing that keeps me thinking it`s why when I adjust the valves to the correct lash that engine idles like shit and has less vaccum than if I give them 0,05 mm more on each side, by the other hand the engine was more sharp and lively (Like an engine whit a narrow LSA angle)
The only answer I found It´s that for greater lash the valve opens later (more slack to compensate before it begins to open) so each cam "reatards" It`s opening point from each other (giving the engine a more wide LSA angle).

But why wouldnt work whit the original values? Ok, I forgot to mention that this head was resufaced 2 times and the cams position wasn`t cheked (the service manual forces the shop to correct the cam position when they skim the head).
I will have to check the cam timing I gess.

What do you think ???

I'll be honest and say...........that shit is beyond me.

I'm not so good with the "WHY??"
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