jonah 1 Posted February 7, 2006 Ok it's not a Pug engine but the same principles apply, and this forum is where the engine gurus are most likely to be reading... Rover K-series 1.4 16v, 92k miles. On cold startup there is a nasty-sounding knock, which is load dependent. It is loudest at small throttle openings - the tone changes slightly with increased throttle but doesn't get louder. The noise disappears off throttle. The knock gets progressively quieter over the first minute or so of running, after which it seems to completely disappear. (There is still a very slight tap that it audible only between about 1000 and 1500rpm, but I think this is unrelated as it is a sharper tone and is not load dependent - probably valve gear.) This noise has always been there to some extent since I've owned the car (about a year and 8k miles), but it has got worse, or at least more frequent, over the last few months. I say frequent because the noise seems to vary in severity depending on ambient temp and possibly how long since the car was last driven. Sounded particulary bad this morning. So, any ideas what this could be? I'm assuming bottom-end since it's load dependent , could it be a little end, broken piston ring, piston slap...? Oil pressure seems to be fine btw, and it does use a little bit of oil (~1 litre every 3000 miles) although there's never any visible smoke from the exhaust. Thanks for any ideas... Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted February 7, 2006 I'd say piston slap but I'm no expert. Try a compression test are they all even readings? Share this post Link to post Share on other sites
jonah 1 Posted February 7, 2006 Yeah someone else suggested piston slap, so what causes it exactly? If it's a worn piston then why does it disappear after a minute's running... that one piston will still be smaller than the rest when it's warmed up (and it's not going to be massively hot anyway after only a minute's gentle driving). The fact that it's worse if the car hasn't been driven for a few days suggests a problem with oil draining out from somewhere, which is why I thought little-end, but I don't know how the oil feed works to them on the Rover (or any other engine for that matter). Also would have thought they'd be worse when the engine was hot and the oil's thinner...? Haven't compression tested it but I'd guess it's ok, idles evenly and there's no sign of heavy crankcase breathing. Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted February 8, 2006 Check the little ends by checking for play in the piston by pushing a long screwdriver down each sparkplug hole. I saw this method used on my makes Renault 19 once. It was quite obvious something was wrong. I suggested piston slap though because the noise is temperature dependent. Have a look through google for informationn on piston slap, as I say I'm no expert here. Share this post Link to post Share on other sites
Adam B 0 Posted February 8, 2006 Sounds like movement in a big end bearing that shuts up as the oil gets to it/warms up. If its not too late you might be able to replace the bearing but depends on if its scored the crank face. It will get progressively worse and you're likely to only hear it at certain revs. I'd get someone to rev the car gently and get your ear close to the underside of the car. You might be able to hear it more clearly then. Share this post Link to post Share on other sites
Guest DRUE1 Posted February 8, 2006 i had the same problem with my old cossie and cos it was a 205 block they where prone to pistonslap.but a cossie rebuild was not cheap so its rebuild time for ya.and it will get worse if you leave it just go bang one day Share this post Link to post Share on other sites
jonah 1 Posted February 9, 2006 Did some searching on Google as suggested, and sure enough it fits the symptoms of piston slap perfectly... Also found various reports saying that loads of K-series (especially 1.4) do this... so I shouldn't need to worry too much yet. Guess it's just a combination of cold weather and being stood for most of the time (so the oil is draining off the bores) that's making it seem worse than usual at the moment. Thanks for the tips! Share this post Link to post Share on other sites
kyepan 291 Posted February 9, 2006 Did some searching on Google as suggested, and sure enough it fits the symptoms of piston slap perfectly... Also found various reports saying that loads of K-series (especially 1.4) do this... so I shouldn't need to worry too much yet. Guess it's just a combination of cold weather and being stood for most of the time (so the oil is draining off the bores) that's making it seem worse than usual at the moment. Thanks for the tips! don't mean to cause you any concern, but i had a 1.4 kseries in the family for years, we thrashed mercilessly it for 130k and it didn't miss a beat.. no noises like the ones you menitoned. Share this post Link to post Share on other sites
