nath 134 Report post Posted March 16, 2010 I have a 1985 318i M10 with 120,000 genuine km. Sometimes there is a god awful clatter from the timing chain, generally once it gets warmer as opposed to cold. The tensioner is pressing against the chain fine, and the spring is intact. The tensioner is oil/spring type. I have replaced a chain on my 230e before which was stretched at 200,000km but had an audible grinding noise as the stretched chain links located on the original- spacing cogs. The 318i does not make this noise. When not rattling, the engine is silky smooth which is apparenty rare for an M10! soooOOOO my question is: Is the problem soley viscosity- related and should I first change the oil with the recommended, or after 25 years regardless of kM, has the tensioner spring lost some of its guts and might it need replacing? This seems less likely, as sometimes the engine does not rattle at all. I'm nor really sure of labour split between oil pressure/ spring pressure. cheers! Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted March 16, 2010 (edited) If your absolutely sure its the chain. Install a new tensioner plunger, not the spring. There was a modified plunger. The oneway valve in the plunger is probably had it. When you fit the new one. Make sure you fill the oil bath it sits in with oil and pump the new plunger up with a screw driver before starting it. You will need the cam cover off to do this. You will see air bubbles coming up in the oil bath. When that stops and you cant pump the plunger anymore, its all set to go. Ring me if your not sure about what I've just said (09) 2722546 Edited March 16, 2010 by *Glenn* Quote Share this post Link to post Share on other sites
nath 134 Report post Posted March 18, 2010 oil changed and so far so good! noise has gone, havent driven on the motorway etc yet though so I will wait and see...... Quote Share this post Link to post Share on other sites
nath 134 Report post Posted June 8, 2010 New piston and no huge chgange, new oil again and a little better, still rattly. Next thing to check/ replace is rockers and rocker shafts.... apparently the m10 and m20 were bad for shaft/rocker wear. Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted June 8, 2010 Have you checked oil pressure ?? Quote Share this post Link to post Share on other sites
nath 134 Report post Posted June 13, 2010 Rattle mysteriously gone after removing and refitting the (new)tensioner yet again... Must have been crap in the oil continuously making its way into the tensioner one way valve? Hard to pinpoint one exact thing that i did to help it on its way, as i played and fiddled/cleaned so much! Quote Share this post Link to post Share on other sites
bimmer boy 21 Report post Posted June 13, 2010 Your new chain should be arriving soon slash already here, nathan Quote Share this post Link to post Share on other sites
nath 134 Report post Posted June 13, 2010 Your new chain should be arriving soon slash already here, nathan i'd hope so it's overdue Quote Share this post Link to post Share on other sites