View Full Version : pics of chain tensioner location?

04-18-2009, 09:57 PM
Just want to know where it is located on a 1991 bmw 318i can't seem to find it...

04-18-2009, 10:20 PM
Does this help?


04-18-2009, 10:22 PM
Chain tensioner is located on passenger side lower timing cover. If you bring your hand along the casing you'll come to a bolt head. I believe it's a 17mm. You can see it if you look closely. Unless you have another car or a replacement chain tensioner in hand I would suggest you get one first before removing it. it is under tension and once the bolt cap is un threaded it may spring out. Then, just remove the spring and unit. The new one should be pre sprung ready to install.
To install it. place the unit back in without doing anything to it. Just install it with a new seal ring and tighten the bolt cap to spec. Start the engine and immediately run the car at 3000 rpm for 30-60sec.(check the instructions-can't remember) until you hear the slapping noise go away. The chain tensioner needs to adjust under load so remember to keep the revs up. Oil pressure has to build for the tensioner to set to the new tolerance. Make sure your oil level is at top and not down a litre. Not good for these engines to run low.

good luck.

04-20-2009, 03:08 PM
Are you replacing the timing belt? I'm not sure if the m10 has a different location for it but once you have everything off to swap the belt it should be as clear as day. Of course I'm talking about the m20, so........

04-20-2009, 03:32 PM
318is doesn't have a timing belt. he's got a rattling chain just from misuse or high mileage.
Typical of the M42 engine. timing chain replacement is usually inherent of low oil level and lots of high revs. top of motor starves consistently and wears out the chain sometimes resulting in breakage. have a look at the chain with the oil cap removed just to see the condition of it. You may need to actually do it if it's really sloppy.

04-20-2009, 04:56 PM
Basically, it's a 17mm bolt head like ceeker said. If you remove the washer fluid container, you'll be able to see it/work on it much easier. This is literally a 5 minute job with blindfolds and a hand behind your back.

04-29-2009, 10:21 PM
thanks alot