Mechanic near Johnstown, PA (Pittsburgh)

[djorevich]

I have what sounds like a marble floating around my engine, comes goes. Probably looking at an engine rebuild for my 76. Does anyone know if a reputable mechanic I can use? I don't have enough time to go into anything this serious right now. 

Edited November 26, 2022 by djorevich
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[Mikesmalaga72]

After trying some higher octane gas and or checking your timing. This guy is around 1.5 hrs from you in Portersville .You may want to inquire with Paul with further questions.  

 

Classic BMW services

e mail: zenwrenchpaul@gmail.com

Phone: (412) 585 2067

[Rich]

The one and only zen wrench, Paul Wegweiser 

[djorevich]

Thank you. I'm going to peek inside the cylinder before I jump. It sounds as if something foreign is bouncing around. Goes completely silent, then knocks like there's a marble in the cylinder. 

[Mikesmalaga72]

It sounds like pinging or detonation. Carbon build up in combustion chambers lights fuel charge before actual ignition which could cause pre ignition under load and varies which you describe. Try a higher octane the higher the better to see if it diminishes somewhat. 

 

[ricsix]

If I was anywhere near western PA, I'd head to Paul Wegweiser.

['76mintgrün'02]

17 hours ago, djorevich said:

Goes completely silent, then knocks like there's a marble in the cylinder. 

 

When does this happen?  If it is at idle, it may (just) be the oil pump chain (or timing chain) slapping against something it shouldn't hit.  My car came with that feature when I bought it eleven years ago.  It comes and goes.  It doesn't scare me.  I don't even mind it anymore.

When I first bought the car I showed it to a friend and he asked what the knocking sound was.  I didn't hear a knocking, only a ticking sound.  I could see it described as a marble bouncing around.  I only hear it at idle when the engine is warm and even then, it is only once in a while.  It's not constant.

[wegweiser]

Other items worth considering:

Ignition timing at idle can have a major effect on valvetrain noise

 

Make sure there are no exhaust leaks at or near the exhaust manifold

 

If the noise is more pronounced when applying throttle, it could be rod bearings.

 

Unless abused (overheated, run out of oil, poor maintenance history, etc) these engines are TOUGH as nails. They can soldier on for thousands of miles, burning oil for years, without any severe damage. 

 

I've encountered a few "fairly new / low mileage" timing chains that got loose and/or stretched within the last 24 months....so it could be something like that.

 

Could also be alternator, loose bracketry, a rattling headlight / headlight grill.... I've heard many noises that sounded like they were from the engine, but turned out to be rattling things nearby. 

 

I'm located about 40 miles north of Pittsburgh and would be happy to take a look / listen to it, if you can transport it up I-79. 

 

Classic BMWs (exclusively) are all I work on... and they have been my singular focus for over 30 years. 

 

All the best to you!

 

Paul Wegweiser

412 585 2067 shop

 

 

[bavariaboy]

Picture your car in one of those bays./  Safe and sound in good hands.

 

Steve

[conkitchen]

If the sound is rhythmic-say noticeably on-time with your rpm's. It could be either a valve is out of adjustment and/or piston slap. The later should go away or become less noticeable once the engine is up to temp. The valve "tick" should become more noticeable once warm.  

 

but what do I know 

Edited December 20, 2022 by conkitchen

[djorevich]

It sounded pretty severe. Unfortunately I haven't had time to dig in. Thanks for the response Paul!  I'm off next week. I'll pull the plugs and take a good look around.  If I'm stumped, I'll get it up to you too see if you can work some magic. Merry Christmas. 

[Dionk]

36 minutes ago, djorevich said:

If I'm stumped, I'll get it up to you too see if you can work some magic.

He does work magic... he is honest, does outstanding work, has impeccable attention to detail, all while maintaining outstanding communication with you on what he is doing. 

 

I shipped my car from MD to PA and he made it run beautifully - drove it home a year ago - still purrs like a kitten.     

Edited December 20, 2022 by Dionk

[Slavs]

On one occasion my car swallowed a brass nozzle from the single barrel Solex. Those things get loose as they are just punched in. The end result was very loud metallic pinging from the head until the valves finally crushed it to pieces and threw it out the exhaust in a matter of scary minutes.  And, that was that. When I removed the head a couple of years later the combustion chamber was all pinged up. If that nozzle wasn't brass and made of something harder, I would have been in trouble.

Edited December 21, 2022 by Alexei

[djorevich]

Finally had a chance to look at the car this weekend. Took a good look and couldn't find anything. Turned over the engine with the plugs out to try to expel anything in there. Put the plugs in, started the engine and it ran like a dream..... for about two minutes. Then I heard what sounds like a sticky valve. I'll get in touch with Paul this week. I may need a surgeon. Thanks everyone, thanks Paul. 

Edited January 15, 2023 by djorevich