engine and drivetrain Noisy timing chain...how long?

[TonyHavana]

My timing chain has been making rattly noises for a while now. I am not driving it hard, but am thinking of driving it down to Watkins Glen for the the Vintage races (about 500 miles return)and do not want to spend anything on this current substitute engine as I am about to undertake a rebuild of my original engine (well, not me exactly, but someone very competent). I know it's not a huge job, but I have no garage to work in, limited tools and skills. Shop wants approx $700.00.

My question is: How long will that noisy chain last if driven gently, or as gently as possible at highway speeds...with a 5 speed.

Thanks in advance

Tony

[2002haus]

Tony,

There is no need to replace the timing chain as these rarely break. They do stretch though over years of use. What you can do though in the meantime (and is something that should be done every 50K miles or so) is to remove and inspect your timing chain tensioner piston.

Chances are that it is worn and is no longer doing the job it was designed to do which is to move with the chain and keep the proper tension. If you remove it and it comes out with any resistance at all then it should be replaced. The regular heat cycling of this steel part along with the stagnant oil ( and the reservoir) that it sits in is not allowing it the proper movement.

Once it is cleaned and or replaced it must be bled properly with NEW motor oil in the reservoir that it operates in. The bleeding procedure is outlined in the factory repair manual. Most likely the small cost of parts and time will get rid of the timing chain noise and provide back the reliability of a BMW 2002 engine the way it was designed.

[Guest Anonymous]

You state the chain is making "rattling noises." How do you know its the chain? Have you taken a stethoscope or the ol-hose to the ear? Does the noise disappear at higher revs? My point is that the valve train is not known for being quiet. It may be that you are suffering from a worn valve train or maladjusted valves.

Another possibility is a loose oil pump chain. From personal experience, when it gets loose and sloppy, it sure gets noisy. Sounds resemble anything from a rod knock to piston slap.

One other thing, and I know this seems unlikely, but what kind of oil are your running? If, for example, you are running 10w30 you may notice considerably more noise from your engine than with 20W50.

Good luck.

[TonyHavana]

Thanks for the tips, guys, and Hart you make some good points.

I was onlyguessing the timing chain, but not sure. Maybe it is valves and coincidentally, the last time I had my oil changed, along with someother work, the guy told me after the fact, that he had put in some 10/30 with some additive, instead of 20/50, which I had always used previously. I mean the guy has an 02 himself, so I assumed (wrongly) that he would put the correct oil in. And at higher revs, there is so much other noise that the "rattle" gets drowned out.

That sounds like a good place to start and a valve adjust, before getting in too deep.

Much appreciated.