Timing chain replaced and some problems

[Eminent]

Hello all.
Today i replaced my old timing chain for a new one.
Altough i'm sure i did everything correct i have a serious problem.
When the marks on the camshaft are lined up, the degrees on the crankshaft say's about 15 degrees before 0.
And thats no good sign.
My questiion: how many degrees do i win if i put the chain one tooth further on the camsprocket?
I did move the crankshaft by hand (did even not use a rachtet) and that works but at a few points i could not turn it further.
I loosen some inlet valve's so i could go on, hope i didn't bend a valve stem.
Btw, the old chain is exactly 1 cm longer than the new one.

[Eminent]

Also, before i began this replacement, i noticed that when the cam marks are lined up the degrees are also a little bit before 0 on the crank.
Maybe the PO put the chain one tooth back to get as close as possible to the 0 degrees on the crank  

[ja17]

Hello Eminent,

Make sure you are using the correct scale. Some of these M130 engines had two separate scales on the dampner. Remove all the spark plugs so that the engine turns easier.  You can carefully feel or see  #1 piston reaching TDC, verif this, coarse by the crankshaft scale and pointer.

Now the problem is not difficult to fix. One link is equal to 18 degrees of valve timing.  So if you move your cam sprocket back on link you should be just a few degrees late, which is a good place to be. 

Remove the front chain rail and bracket  (on the cylinder head). Remove the front 22mm cam shaft bolt. Gently tap the sprocket with chain off the end of the camshaft without splittining the chain. Reset the sprocket one link late.  Move the camshaft just enough so that the key aligns to the sprocket and tap the sprocket back onto the cam. You will have to depress the chain tensioner while doing this by pressing down on its sprocket. Some force will be required to depress the tensioner so that the sprocket will slide on the end of the cam. Please take caution to make sure nothing drops into the chain gallery.


Rotate the engine by hand (in the normal direction of rotation) to make sure that the valve timing is correct .

Keep us upto date.
Joe

[Eminent]

Hello Joe, thanks for your reply.
I have the version with only one scale.
I did remove the spark plugs for an easier turning.
When it was not possible to turn anymore i loosen the inlet valve which was open at that time a bit so i could go further.
Later today i will go on with the job and hope to reset the cam timing.
If it's indeed so that one tooth is 18 degrees it will be about 3 degrees ATDC after resetting the cam.
You'll hear from me.
Regards Rini.

[Eminent]

Succes! I tapped the camsprocket from the camshaft and replaced the chain.
It was difficult to move the tensioner down so i decide to loosen the large nut a bit.
That worked, the tensioner was now easy to move downwards.
Put the sprocket back on, checked the timing and....   it was excactly the same as with the old chain.
Think that it had to do with bleeding the tensioner, cause after a full rotation by hand it was better.
About 3-4 degrees ATDC.
I was hoping that the tap-tap-tap sound would be eliminated also but that is just a bit less.
Think i have to check some connection rod bearings as wel.
A few questions i have.
As i mentioned before the old chain is 1cm longer than the new one, is this much? I mean, is the old chain at the end of it's life when it's 1cm longer?
Do i have to reset the ignition timing as wel?
And, is it common that "mechanics" move the chain one tooth back to get close to "0" TDC.
Thanks.
Regards Rini.

[ja17]

Hello Eminent,

Three or four degrees ATDC for the valve timing is pretty good. I would not worry about getting it closer. Yes, you should check the ignition timing.

The tapping sound can be valves out of adjustment, a worn rocker arm, or valve cover hold down straps rubbing against the camshaft.