1995 525i Excessive valve noise

[SCat]

I've been told that the valves on the M50 engine can not be adjusted. The car runs great but sounds like a deisel. Anyone know what I need to do and how much it's going to cost me?

[Russell]

Hard to tell without knowing the mileage and maintainance history.

Does it make noise on the first cold start of the day

Mine would rattle when first started. Go to a 0w40 to 5w40 synthetic oil and a startup rattle should go away.

If not I think some posters have said that the Vanos system can rattle. Others may know more. Good luck


I've been told that the valves on the M50 engine can not be adjusted. The car runs great but sounds like a deisel. Anyone know what I need to do and how much it's going to cost me?

[Bill R.]

its a rattle when warmed up then this bulletin may helphttp://www.bimmernut.com/%7Ebillr/images/Dickslifterrattle2.jpg






I've been told that the valves on the M50 engine can not be adjusted. The car runs great but sounds like a deisel. Anyone know what I need to do and how much it's going to cost me?

[SCat]

Thanks Bill and Russell. It doesn't rattle until the engine gets warmed up.

[Bill R.]

m50 motor and thats what it turned out to be. Here's an earlier link and if you do a search on his name you'll find more posts on it.
(http://www.bimmer.info/forum/showthread.php?p=22393#post22393)







Thanks Bill and Russell. It doesn't rattle until the engine gets warmed up.

[iainand]

anyone know if this would affect my engine, M51 2.5 turbo diesel?? my engine is very noisy from the camshaft area

[Bill R.]

we don't get them in the US i haven't seen one yet.




anyone know if this would affect my engine, M51 2.5 turbo diesel?? my engine is very noisy from the camshaft area

[Bill R.]

oil pump is a completely different design driven off the front of the timing cover like a toyota 22r , you have an oring seal between the pump and pickup tube instead of a gasket.. same problem could apply though.





we don't get them in the US i haven't seen one yet.

[Kai@e34.de]

anyone know if this would affect my engine, M51 2.5 turbo diesel?? my engine is very noisy from the camshaft area
oil pressure too low and/or worn hydraulic valve lifter(s) i guess.

[liquidtiger720]

Okay, I dont want to hijack...but what if i get a rattle at start up...sounds like a diesel till its warmed up, then...it rattles when I am on the throttle around 2k rpm? Im guesssing its the same problem, but I just want to make sure. Is this something a idiot DIY can do?

[Kai@e34.de]

same here:
oil pressure too low and/or worn hydraulic valve lifter(s) i guess. or your vanos unit is out of order, but the the noise should not disapper when the engine is warmed up.

[DanDombrowski]

Bill, is there any way of determining if the oil is foaming from this symptom or another? The only way I can think of is to drain it.

Reason I ask is because I have a tapping noise coming from the front of my M50 after it has warmed up, and I THINK its actually either coming from the A/C compressor or the fan clutch. My A/C has always made a grinding noise when its on, so mabye its getting worse.

Its definitely coming from the front of the engine, near the vanos unit. When I put my ear close to the rear of the engine, I can hear the valves opening and closing with minimal noise. If I had this oil problem, would all the valves be making noise? Or just the front ones?

I'm already running 0-40 Mobil 1. If its the usual vanos rattle (although its never been that loud), I can live with that, or if its the fan clutch, again, I don't really care. I just want to make sure I'm not damaging my valves by low oil pressure.

[Kai@e34.de]

Its definitely coming from the front of the engine, near the vanos unit. When I put my ear close to the rear of the engine, I can hear the valves opening and closing with minimal noise.not unusual.

If I had this oil problem, would all the valves be making noise? Or just the front ones?you should hear all the valves if you engine has a too low oil pressure. how long does your oil pressure lamp in your dash take to go out after you've started the (warm) engine? if you increase the engine rev, does the noise increase, too?


I'm already running 0-40 Mobil 1. If its the usual vanos rattle (although its never been that loud), I can live with that, or if its the fan clutch, again, I don't really care. I just want to make sure I'm not damaging my valves by low oil pressure.
start the engine, take a long extension from a 1/2" ratchet, place one side on the valve cover (over the vanos unit), the other end right upon your ear. works like a stethoscope. increase the rev, you'll hear if the noise comes from the vanos unit. although i'd take a 10W-40 oil for the M50 engine.

[ryan roopnarine]

i have a diesel bus noise up front. i've always suspected that it was the main hydraulic tensioner. someone said that the bearing does that when its dead. im thinking that you have the same. it does this at weird times, not necessarily when hot or cold, usually both. when it isn't, the car is quiet as hell, quiet enough that the only noise one can hear is the clicking of the fuel injectors, which is pretty quiet.


Bill, is there any way of determining if the oil is foaming from this symptom or another? The only way I can think of is to drain it.

Reason I ask is because I have a tapping noise coming from the front of my M50 after it has warmed up, and I THINK its actually either coming from the A/C compressor or the fan clutch. My A/C has always made a grinding noise when its on, so mabye its getting worse.

Its definitely coming from the front of the engine, near the vanos unit. When I put my ear close to the rear of the engine, I can hear the valves opening and closing with minimal noise. If I had this oil problem, would all the valves be making noise? Or just the front ones?

I'm already running 0-40 Mobil 1. If its the usual vanos rattle (although its never been that loud), I can live with that, or if its the fan clutch, again, I don't really care. I just want to make sure I'm not damaging my valves by low oil pressure.

[Bill R.]

one or two. Since your only hearing one or two you could have a bad hydraulic element on one or so valves only. It may not be low oil pressure related at all. But its more likely that its the idler or compressor puller bearing. I would warm it up until it makes the noise then remove the belts an start it and run it for a minute or so , as long as you don't run it more than about a minute it won't hurt anything or overheat, but since the pump won't be turning you don't want to run it too long... Also when you have the belt off you can spin the pulleys one at a time to try and track down any noise. If the oil is foaming an aerated it may settle down a lot by the time you could drain it to inspect. Heres a bulletin on one noise you may be hearing thats normalhttp://www.bimmernut.com/%7Ebillr/images/m50ping-1.jpg

And here's a bulletin on how to inspect each hydraulic valve element to see if one of them is bad or not pumping uphttp://www.bimmernut.com/%7Ebillr/images/hva1.jpg
http://www.bimmernut.com/%7Ebillr/images/hva2.jpg


Bill, is there any way of determining if the oil is foaming from this symptom or another? The only way I can think of is to drain it.

Reason I ask is because I have a tapping noise coming from the front of my M50 after it has warmed up, and I THINK its actually either coming from the A/C compressor or the fan clutch. My A/C has always made a grinding noise when its on, so mabye its getting worse.

Its definitely coming from the front of the engine, near the vanos unit. When I put my ear close to the rear of the engine, I can hear the valves opening and closing with minimal noise. If I had this oil problem, would all the valves be making noise? Or just the front ones?

I'm already running 0-40 Mobil 1. If its the usual vanos rattle (although its never been that loud), I can live with that, or if its the fan clutch, again, I don't really care. I just want to make sure I'm not damaging my valves by low oil pressure.

[Jean@MtMiguel]

same here: or your vanos unit is out of order, but the the noise should not disapper when the engine is warmed up.
Lubro Moly products( no I am not a Lubro customer rep/salesman) have a variety of engine enhancement products, for sticking valves , fuel injector cleaners, oil products, I've been using them for a while and getting good results out of them, they're cheaper than taking the engine apart.