R51/3 - metallic ticks from one side of the motor

[Werner1111]

You might buy a mechanic's stethoscope and use it to try to pinpoint the location of the noise. I find them helpful. They're cheap.

Other than being a mess, could one run the motor with the valve covers off for a few moments, if one concludes the noise is coming from the head?

Also, if your carbs aren't well balanced, one side might sound different from the other as they would be carrying different amounts of the load.

Even though you have a new electronic ignition, I'd still hit the timing mark with a strobe light to make sure it's timed correctly and that you don't have differential timing. From my minimal experience, that will cause the two sides to sound different. Just because it's new doesn't mean it's working correctly.

Forgive me if I'm repeating the suggestions of others.

[Micha]

Evening Werner,
Thank you very much for your time and suggestions.
Did you hear the ticking?
I understand that boxer's do sound different on each side, but I am also trying to understand if you guys hear what I mean?
Can you hear those metallic ticking on the right size? Or is my wife right?

The mechanic's stethoscope is a great idea.

[Werner1111]

I listened to all four files two times. I can hear a difference between the left and right, but I don't know that I could honestly say I can discern a ticking sound on the right. Maybe just a little. If anything, the left side at faster idle has more ticking noise than the right, to my ear, which is opposite of what you're suggesting. I'm sure the sound is more apparent in person.

Another thought - What if you were to slightly tighten up the valve clearance on the right side to see if there is a difference in the noise? If the noise changes, then you know the culprit. I wouldn't necessarily leave it with tight clearance. I'm just thinking of it as an experiment.

[Werner1111]

If you do the experiment, I'd only do one valve at a time.

[Daves79x]

Has anyone suggested checking the end float on the rocker arm shafts? They should have very little noticeable play - just enough to let oil pass.

Dave

[wa1nca]

He posted this link from boxer2valve
https://www.youtube.com/watch?v=yCTpwScRE5w

[vechorik1373]

Another possibility that no one mentioned is a bent push rod. Get the cylinder at TDC and get your eye down there and look at where the push rod enters the hole in the head, and spin the push rod with your fingers. If you see the push rod wobble, you have a bent push rod. Once they get bent, they will continue to bend under load. The only cure is to buy a new one.
A bent one will "tick" under load. Obviously, check all 4. Replace all the bent ones.
The part number is 11 32 0 033 170----push rod R51/3-R50S.

When I ran Bench Mark Works, we had them in stock. Max BMW has all my stock now.

[Micha]

Thanks, I already checked all 4.
Replaced 2 just to be on the safe side (they still where ok).
Unfortunately it did not make any change.
Thanks again!

[malmac]

did you get this sorted?

Another cause can be a bent camshaft.
Dont ask me how I know.


Mal

[Micha]

Yes, all good now.