Guest dave42 Posted November 5, 2007 Share Posted November 5, 2007 hi all. i was wondering if anyone can help me. When i start the car in the morning there is quite a loud knocking/rattle sound that lasts merely a second before disappearing completely. For the rest of the journey there is no knocking at all, its only as the car is started. any ideas what may be causing this? thanks for any help. dave Link to comment Share on other sites More sharing options...
NeoFuture Posted November 6, 2007 Share Posted November 6, 2007 if you stop and start the car when warm does it knock again for a second ? Link to comment Share on other sites More sharing options...
Paul Whiffin Posted November 6, 2007 Share Posted November 6, 2007 Is it just when its cold? Sounds like an engine rebuild will be looming soon, saying that, we've got a few customers cars that have been doing this for a long time now and still going strong. Could just be luck of the draw though. Link to comment Share on other sites More sharing options...
bodilx6 Posted November 6, 2007 Share Posted November 6, 2007 Mine's doing the same. Only when cold. I'm quite sure the engine is in good shape in general as it pulls very well, healthy dyno, only 60k miles and so. The only thing I know about as an issue is the probably worn valve stem seals due to a bit of a blue puff once in a while when moving off from a full stop. The sound itself isnt very loud in my case, it took several months of ownership until I noticed it, but its definately there. Dave42, is the "loudness" of the sound changing for you depending of ambient temperature? Mines in an underground garage, so I have a more or less constant startup temp. Anyone got an idea of what this can be? Link to comment Share on other sites More sharing options...
Guest dave42 Posted November 6, 2007 Share Posted November 6, 2007 NeoFuture - No, when the car is warmed up and i start the engine again there is no sound. Is that good or bad? Paul - In the back of my mind i thought it would be serious, do you know exactly what the noise is? Just out of interest. bodilx6 - Yes the loudness does depend on temp. In the summer it wasn't that loud but now the weather is getting colder it seems to get louder. I think the valve stems are shot so i was planning on getting them done soon. Anyone know how much the valve stems and engine rebuild will cost? I live in hampshire and have heard of a place called toyodatech which apparently is quite good with imports. Anyone had any experience with them. Thanks for the replies, Dave Link to comment Share on other sites More sharing options...
SatSport Posted November 6, 2007 Share Posted November 6, 2007 one for a CW teccy explanation, probably the oil not geting through the pump/bearings quick enough Link to comment Share on other sites More sharing options...
georigg Posted November 6, 2007 Share Posted November 6, 2007 Hi Dave, Next time you start from cold, have a look at the oil pressure light and see if the knocking noise coincides with the short period of time that the oil light is ON as the engine starts, if so it could be the big end bearing shells are now worn, allowing the big ends to rattle at start-up. For info, if this is the problem, you can "help" the situation by starting the engine in the morning, and immediately it fires, switch off again, then back on just as the engine dies until the oil light stays off at which point you can let the engine run, this will give sufficient revs to turn the oil pump to establish oil pressure without the full load of ignition on the pistons being transferred through to the big-ends, which will otherwise occur if you just start it and allow it to rev from cold. Of course if this is not the problem above is not applicable!!!! Rgds George Link to comment Share on other sites More sharing options...
Sparky Posted November 6, 2007 Share Posted November 6, 2007 Mine does the same and the oil light stays on for a good second or 2 so most likely that is the problem. TT soon so not to worry! lol Link to comment Share on other sites More sharing options...
Paul Whiffin Posted November 6, 2007 Share Posted November 6, 2007 Probably knackered oil pump I would thought causing oil starvation, the noise you can here is probably your big ends or mains, either way its only a matter of time before it gets worse. Link to comment Share on other sites More sharing options...
Epic Posted November 6, 2007 Share Posted November 6, 2007 mine makes a little knocking sound to for a secound, you all got me worryed now!!! Link to comment Share on other sites More sharing options...
Sparky Posted November 6, 2007 Share Posted November 6, 2007 I really don't think its much to worry about. When the noise lasts longer and you get blue smoke coming out of your exhaust then start worrying! Link to comment Share on other sites More sharing options...
Guest dave42 Posted November 6, 2007 Share Posted November 6, 2007 Hi Dave, Next time you start from cold, have a look at the oil pressure light and see if the knocking noise coincides with the short period of time that the oil light is ON as the engine starts, if so it could be the big end bearing shells are now worn, allowing the big ends to rattle at start-up. For info, if this is the problem, you can "help" the situation by starting the engine in the morning, and immediately it fires, switch off again, then back on just as the engine dies until the oil light stays off at which point you can let the engine run, this will give sufficient revs to turn the oil pump to establish oil pressure without the full load of ignition on the pistons being transferred through to the big-ends, which will otherwise occur if you just start it and allow it to rev from cold. Of course if this is not the problem above is not applicable!!!! Rgds George This is exactly right. The sound lasted exactly as long as the oil light was on. I tried what you suggested tonight before coming home and it worked, no knocking. Looks pretty conclusive. Not the best news i've ever had but nice to pretty much know what it is and how to help the situation, as you say, until i get it sorted. Anyone know how much a stock engine rebuild costs including valve stem seals? Thanks for all help so far, much appreciated. Link to comment Share on other sites More sharing options...
Epic Posted November 6, 2007 Share Posted November 6, 2007 stock engine rebuild costs including valve stem seals? not cheap i would have thought, bloody hell... is your knocking really bad then? or more of a small tap like what i seem to have.. Link to comment Share on other sites More sharing options...
Guest dave42 Posted November 7, 2007 Share Posted November 7, 2007 not cheap i would have thought, bloody hell... is your knocking really bad then? or more of a small tap like what i seem to have.. No it's not really bad, it would just be nice to have it all running perfect. But then cars rarely do! If the price is prohibitive then ill leave it for now but if its within my price range then i might get it done. Link to comment Share on other sites More sharing options...
bodilx6 Posted November 7, 2007 Share Posted November 7, 2007 Il'll try the same thing tonight, but have never seen the oil lamp being on. It is the yellow of the two we are talking about, right? To get the stem seals fixed, the top needs to go off but I think the motor can stay in. So if you find a mechanic thats not to expensive per hour, I think you will get off cheap. What do you define by a engine rebuild? My understanding regarding the stem seals are that its not a very big deal, as long as the puffs of smoke aren't getting significant. I think almost all BPU'ed supras got a bit of flow through the seals if they havent been changed. The cars do have some years on them. What I'm not sure of is if the rattleing problem this discussion is really about is anything to worry about? Georigg, what is "the big end bearing shells" and how are they changed/fixed? Link to comment Share on other sites More sharing options...
Digsy Posted November 7, 2007 Share Posted November 7, 2007 Il'll try the same thing tonight, but have never seen the oil lamp being on. It is the yellow of the two we are talking about, right? No, the oil pressure lamp is the red one. The yellow is oil level. Link to comment Share on other sites More sharing options...
Chris Wilson Posted November 7, 2007 Share Posted November 7, 2007 It needs a crank grind and bearings, and a new oil pump. Could be cheaper to find a good used engine if you don't plan on keeping it too long, or just cross your fingers and don't touch the accelerator as you start it, just let it fire up and idle. May go on for ages as it is, may fail spectacularly next time you drive it, luck of the draw, as said earlier. Link to comment Share on other sites More sharing options...
Epic Posted November 7, 2007 Share Posted November 7, 2007 mine makes a small tapping noise on start up to.. should i be worryed? Link to comment Share on other sites More sharing options...
SteveL Posted November 7, 2007 Share Posted November 7, 2007 Probably knackered oil pump I would thought causing oil starvation, the noise you can here is probably your big ends or mains, either way its only a matter of time before it gets worse. Sounds familiar ! I'm taking the advice that both Paul and Chris have stated, but I've been lucky - mine started at least a year ago. Link to comment Share on other sites More sharing options...
Epic Posted November 7, 2007 Share Posted November 7, 2007 how much would a new oil pump set me back, and whats the install time better be safe than sorry just in case thanks Link to comment Share on other sites More sharing options...
Paul Whiffin Posted November 7, 2007 Share Posted November 7, 2007 Sounds familiar ! I'm taking the advice that both Paul and Chris have stated, but I've been lucky - mine started at least a year ago. Yeah and you've been ragging the shit out of it round the track! We'd better get that engine built ASAP. Link to comment Share on other sites More sharing options...
SteveL Posted November 7, 2007 Share Posted November 7, 2007 Yeah and you've been ragging the shit out of it round the track! We'd better get that engine built ASAP. ... be a good contender for an investigation then .... Link to comment Share on other sites More sharing options...
mattanna Posted November 7, 2007 Share Posted November 7, 2007 My Aristo did this before it's rebuild, i have said many times before, oil pump may well be on it's way out but more likely oil pick up strainer mesh is blocked, which is common on these, hence causing oil starvation.Big end shells sound suspicious also:( Link to comment Share on other sites More sharing options...
Paul Whiffin Posted November 7, 2007 Share Posted November 7, 2007 Literally just stripped an engine down a moment ago, my hands are still covered in that stinky oil smell you get from an engine! The engine had the same symptons which turned into a severe knock, its spun a big end and a main bearing, crank is for the bin along with a rod as well. No blocked oil strainer though. New crank, bearings, rod, oil pump and a refresh is in order on this one. Link to comment Share on other sites More sharing options...
Guest dave42 Posted November 7, 2007 Share Posted November 7, 2007 Literally just stripped an engine down a moment ago, my hands are still covered in that stinky oil smell you get from an engine! The engine had the same symptons which turned into a severe knock, its spun a big end and a main bearing, crank is for the bin along with a rod as well. No blocked oil strainer though. New crank, bearings, rod, oil pump and a refresh is in order on this one. So i'm assuming it would be simliar for me. Would you be able to tell me what this will be costing the customer? Its intersting that the gentlemans idea above worked (cranking the motor a couple of times without letting it fully start) and the noise was gone. Could that not suggest its just an oil pump/strainer problem or will dodgy cranks/bearings/rods etc cause a lack of oil flow? Link to comment Share on other sites More sharing options...
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