I have a ticking sound, particularly on cold start, that sounds a lot like noisy tappets. I read recently that this is a failing cam chain tensioner, and that it is a pretty easy fix.

I have searched the forum and looked through the DIY archive and can't find anything.

Can anyone confirnm the problem, and point me to a write-up of the repair, if one exists? TIA

Here are a couple of related writeups that I found by doing a quick www.google.com search for "BMW E36 timing chain tensioner":

http://www.unofficialbmw.com/e36/engine/e36_timing_chain_tensioner.html

http://e30m3performance.com/installs/installs-3/tensioner/

Thanks. I found some more info using "timing chain" rather then "cam chain." It looks like apretty easy job. It also seem there are a lot of diferent reasons for valve train noise - lifters, Vanos, cats...I wonder if I don;t have a different problem.

I read alot about M3 replacements, but not so much about the E36 M50 engine. Is there any "upgrade" that should be done, or are most people just replacing it with a new standard OEM part?

On cold start, the tapping sounds more like a lifter before being pumped up.

How many miles on the car?
Is this coming from one valve or and orchestra of tapping?

A failing tensioner will make the chain really noisy, like ball bearings in a box...

It sounds like a single valve, definitely not the "box of marbles" I've heard used to desribe some of the other problems.

Engine has 106k on it, runs great otherwise. In fact there doesn't seem to be any performace loss, it's just embarrasing to sound like a '67 Chrysler or something! And if it IS a real problme I wanted to catch it before it got worse...

If it's a single valve, you probably have a bad lifter. Does the tapping sound go away after the car warms up a bit?

If it does, I wouldn't worry *too* much. Replacing a lifter ain't too bad if you're mechanically inclined. Otherwise, it'll require paying someone to take the cams out and the cost of a new lifter. They're reasonably priced... I'd guess $20 at the most for the lifter.

FYI, the new style primary E36 timing chain tensioner is supposed to apply more pressure to the timing chain immediately after startup due to its double piston design (one of those links above explains this). Your old timing chain tensioner may not be failed, just not applying as much pressure to the timing chain as it once did (it uses oil pressure in combination with an internal spring to force the piston against the timing chain guide rail). If the internal piston is worn a little and clearances have opened up, it may be letting oil pressure past the piston and providing less applied force to the timing chain. Regardless, the new design primary timing chain tensioner really reduced the cold start noise on my 95 M3.

I still have a bit of the "marbles-in-a-can" sound, but only noticeable with the hood open and standing over the engine with the engine hot or cold when the RPMs pass through 1500 rpm. But from the research I have done, this is the VANOS unit and there is little benefit to changing the unit just due to this noise.

Thanks. I was reading that too.

Do you know when they switched to the "new style" tensioner? Is it a direct swap into all E36 325's or is it only for the M3?

Well, I changed the oil this weekend and the sound has gone away, even on cold starts (if you call 90 degrees cold!)

Redline 10W40 to the rescue.

I'm still going to keep an eye on things, in case it comes back or gets worse.