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DonC
05-28-2004, 04:13 PM
I have a valve train noise in my 1990 535 that is making me nuts! When I "blip" the throttle I hear a clatter just before the engine settles back to idle - there is no unusual valve train noise when the revs are up. I am not taking the revs to the redline - only to about 2000 to 2500 rpm. To my ears it sounded like loose valve clatter so I adjusted the valves - no change. Could this be a timing chain tensioner problem?

Any leads/ideas will be greatly appreciated!

Thanks!
Don

DonC
05-28-2004, 04:22 PM
One more thing - the engine has 126k on the clock

Jeff N.
05-28-2004, 09:13 PM
gee..i'm almost wondering if this might not be a rattling dual mass flywheel. Auto or manual?

Unregistered
05-28-2004, 11:36 PM
can u tell me if an 535 engine will fit on a 525 both 95

Jeff N.
05-29-2004, 12:41 AM
Sure. You'll just need to change the engine, the engine harness, the electronics, the tranny and the driveline and maybe the rear end. Don't forget the radiator, airbox and other misc items. :)

George M
05-29-2004, 07:01 AM
Don...the big six is known for its valve train noise. You can pop the valve cover and check the timing chain tension with a long blad screw driver. While the V/C is off you can set the valves. Try to see if the noise is local to a specific cylinder or overall. Many of us can have had these heads apart and can provide some insight but you have to provide a lot more information, in terms of what has been done to resolve the problem...if your valves were just adjusted...when it started to occur/was it more quiet before etc.
No real mysteries to the great big six...wonderful engine.
George

DonC
05-29-2004, 08:05 AM
I bought this car late last year. The car was maintained by Bavarian Machine Specialties (HIGHLY recommended) in Houston for the past 8 years. All service intervals were followed religously. I noticed the noise back around March, but got around to doing the valves in early May. When I open an engine, I always check the valve clearances. In this case there were only a couple of valves that were slightly loose. I adjusted all the valves - the noise did not get any better or any worse. I have tried to pin-point the source of the noise witout success
The car, unfortunately, has an automatic. Considering the service history and relatively low mileage of this car, and the reputation of the big-six, I'm at a loss.
Thanks for your input!

Jr ///M5
05-29-2004, 08:25 AM
The injectors for the 535 are known to be slightly noisy also, at least they were on my old one. Nothing wrong with it, just sounded like a repeated sharp crack. Other than that, the valves would sound like a sewing machine when adjusted properly.

Making note of the dual mass flywheel noise that occurs at idle, would imitate the sound of a rod knocking, only lower and not quite as pronounced. Again, nothing really wrong here, just the nature of the beast.

With the engine idling and the hood open, listen to it with your eyes closed, try to tune in to just the valve clatter, it should sound like a sewing machine. Then listen for the injectors, they will be louder and more of a sharp crack sound. In both cases the sounds should be rythmic and constant, both almost dissapearing when the engine is revved. Just don't rev the engine too much in Park or neutral or you'll be listening to your new tranny failure.

George M
05-29-2004, 10:05 AM
in addtion to what Jr wrote...incidently Don your automatic car doesn't have a dual mass flywheel...again, what you need to identify is if all the valve train sounds uniform or if it is an isolated rocker or injector creating the noise. Check your banjo bolts to be sure they are snug. Inspect the cam lobes to see if they are smooth and getting adequate lubrication...cam should be wet front to back. You may have missed a valve when adjusting them...VERY easy to do. I too check mine all the time and there always seems to be one out. If you identify an isolated cylinder...use a hose or long screw driver in lieu of a mechanics stethoscope versus a chorus of racket...then it may be a common failing eccentric. Unlikey though that all your eccentrics are bad if
have an aggragate of noise. What did you set your valves to cold?
George

Robert K
05-29-2004, 12:05 PM
If I remember correctly, you SHOULD NOT rev an automatic E34. I believe there is a weakness in a seal in the tranny. Revving the engine while the transmission is in park can blow this seal out. Bad news I'm sure. Bill R may be able to back me up on this, but after I read it, I never, ever rev mine while in park. I don't even like to think of a rebuild or buying a new tranny.

Grace and peace,

Robert K
1991 535i

George M
05-29-2004, 01:39 PM
I rev mine all the time in Park...lol. Am challenging the trans to blow so I can install a Getrag 5 speed. Not really. If the A-clutch input shaft seal is worn, then you can overpressurize the A-clutch in Neutral or Park only if the car was been put in drive just before. After a long cool down or after initial start up, you can rev the engine in P or N without incident. The fix is to replace the steel O-ring with a Teflon seal. Winfred has a superb write up on the procedure as he has done a lot of them.
George

Dick Schneiders
05-29-2004, 05:24 PM
The later ZF's and the GM auto trannys on the 525's should not be a problem


If I remember correctly, you SHOULD NOT rev an automatic E34. I believe there is a weakness in a seal in the tranny. Revving the engine while the transmission is in park can blow this seal out. Bad news I'm sure. Bill R may be able to back me up on this, but after I read it, I never, ever rev mine while in park. I don't even like to think of a rebuild or buying a new tranny.

Grace and peace,

Robert K
1991 535i

George M
05-29-2004, 05:33 PM
All E-34's and E-32's with ZF 4HP 22 EH and M-30 engine through 1992 had this issue.
George