villa.1 Posted March 1, 2017 Report Share Posted March 1, 2017 Hi All, After 6 months off the road fitting EFI amongst other things, I took the car out for a test drive /shake down today ahead of its rolling road next week. The standard tr6 map that was installed worked ok to get fired up but the timing was definitely a little out. After 10-15mins i put my foot down and got a tapping/rattle at 4000 revs onwards getting quite shrill at above 5000 rpm as soon as I backed off it eased but I decided to limp home and over the next 10 miles it got progressively worse. It now sounds like i have an angry dwarf with a hammer in the engine above 3000 revs and a fairly loud clear tapping noise on tick over. Something has clearly gone quite wrong in the engine but i wanted some help to try and establish whether its head or bottom end. I have checked compression which was +/- 5psi 170PSI on 1,3,4,5,6 and 140psi on 2. all spark plugs where light brown and similar. Regards Steve Quote Link to post Share on other sites
RogerH Posted March 1, 2017 Report Share Posted March 1, 2017 Hi Steve, after you 6 month lay up did you put in new/good/petrol. Your first symptom of rattling when foot put down sounds like 'pinking'. The angry banging may be associated but I don;t know Roger Quote Link to post Share on other sites
villa.1 Posted March 1, 2017 Author Report Share Posted March 1, 2017 Fuel is fresh, its run fine in the garage on the ramps it misfired a little due to the set up not being perfect but it was only today 20mins into its first road test that the issue really started. Quote Link to post Share on other sites
Alec Pringle Posted March 1, 2017 Report Share Posted March 1, 2017 Long screwdriver, wooden handle works well, and use it as a stethoscope - pointy end on the engine, handle against your ear . . . . . Alternatively a long stiff tube . . . . That should enable you to ascertain the approximate location of the noise. Cheers Alec Quote Link to post Share on other sites
iain Posted March 1, 2017 Report Share Posted March 1, 2017 Go with Alec, find the source of the noise through careful listening, then........ Quote Link to post Share on other sites
rhino_mac Posted March 1, 2017 Report Share Posted March 1, 2017 then........ ..........prepare to get your wallet out. Seriously though, good luck. Hope it's nothing a turn of a screw won't sort. Quote Link to post Share on other sites
Tim D. Posted March 1, 2017 Report Share Posted March 1, 2017 Always worth lifting the rocker cover. Could be a Broken rocker or something dislodged and bouncing around. Tim Quote Link to post Share on other sites
villa.1 Posted March 1, 2017 Author Report Share Posted March 1, 2017 Thanks, I removed the rocker cover and ran on tick over, nothing appearers broken or sticking. Quote Link to post Share on other sites
marki Posted March 1, 2017 Report Share Posted March 1, 2017 Hi Steve. I'd have a look inside the bores, to make sure nothing has fallen in while you had the inlet manifold off. I know it sounds like a long shot but it happened to me when I rebuilt a Lotus engine years ago. I still have no idea how it happened. Good luck, I'd be interested to know how the mapping goes. Mark. Quote Link to post Share on other sites
Austin Branson Posted March 1, 2017 Report Share Posted March 1, 2017 Hello Steve, it does indeed sound like 'pinking'. Pinking us pre-detonation, usually caused by over-advanced timing, too-weak a mixture or low octane fuel. Or any combination. It usually leads to holed pistons. Unlikely to cause a hammering noise, unless it has damaged the big-end bearings. I guess that's possible, but I understand these can be changed with engine in situ (though I've never done it myself). Let us know how you get on. Austin Quote Link to post Share on other sites
harrytr5 Posted March 1, 2017 Report Share Posted March 1, 2017 If you have used Emeralds kit they can diagnose over the phone with your lap top plugged in and connected to WIFI. It works! Regards Harry Quote Link to post Share on other sites
Peter Cobbold Posted March 1, 2017 Report Share Posted March 1, 2017 It is almost impossible to get an an engine to pink at tickover. The tapping getting worse above 4000rpm also does not seem to me to be detonation. As is is worse above 3000rpm, the point of max disy advance, I wonder if it is a c/f advance weight spring at fault, allowing the weight to hit the housing.That's where I'd put the screwdriver stethoscope first. Peter Quote Link to post Share on other sites
oldtuckunder Posted March 1, 2017 Report Share Posted March 1, 2017 stethoscope test definitely, hope its something simple like Peter's suggestion, but from the Angry Dwarf description etc. sound just like my total BE failure at Shelsley in 2015. Six months standing with odd bit of manual turning over, and no forced pre oiling before start up could have meant a very dry bearing on start up. Hope not though. Alan Quote Link to post Share on other sites
jerrytr5 Posted March 1, 2017 Report Share Posted March 1, 2017 Could be head gasket between cylinders. Happened to me couple of months ago driving home from work in the Hurricane (Spit 1300 engine). Started off just like pinking and within 3 miles considerably louder and well down on power. Number 2 down on compression could be your clue. In my case, fixed with a new head gasket. Jerry. Quote Link to post Share on other sites
Motorsport Mickey Posted March 1, 2017 Report Share Posted March 1, 2017 . It now sounds like i have an angry dwarf with a hammer in the engine above 3000 revs and a fairly loud clear tapping noise on tick over. Steve Hi Steve, Maybe because you haven't seen him is it possible you have misidentified the dwarf and actually he's a midget as reported to the Quantas engineers by one of their pilots on their snagging list ? And perhaps, the best Qantas joke... Qantas Pilot: Noise coming from under instrument panel. Sounds like a midget pounding on something with a hammer. Engineers: Took hammer away from midget. Hope you can find the little fella and treat in a similar manner. Mick Richards Quote Link to post Share on other sites
john.r.davies Posted March 1, 2017 Report Share Posted March 1, 2017 Is the crank wheel; fouling the sensor? John Quote Link to post Share on other sites
Guest ntc Posted March 1, 2017 Report Share Posted March 1, 2017 Little end running dry? Quote Link to post Share on other sites
graeme Posted March 1, 2017 Report Share Posted March 1, 2017 Exhaust manifold could be leaking at the head interface! Graeme Quote Link to post Share on other sites
villa.1 Posted March 1, 2017 Author Report Share Posted March 1, 2017 Loads of great advice thanks all, i just had it ticking over with the rocker covers off and its best described as a loud tapping @ 600rpm which turns into a proper hammering noise at anything above 1500rpm. i had hoped it was just a head gasket as suggested but the noise is too severe and metalic me thinks for it not to be the bottom end. I guess the best plan of attack is to get the sump opened up and hope nothing horrible falls out! regards Steve Quote Link to post Share on other sites
Ben Freer Posted March 1, 2017 Report Share Posted March 1, 2017 Do the easy things first. Check out what Graeme suggested first before you rip it apart ???? Oh and BTW yes you can change big end bearings from the sump. I did it once in the street. (I was young and skint)???? Quote Link to post Share on other sites
Guest ntc Posted March 1, 2017 Report Share Posted March 1, 2017 Run it with one plug at a time removed. Quote Link to post Share on other sites
Motorsport Mickey Posted March 1, 2017 Report Share Posted March 1, 2017 (edited) Hi Steve, Nobodies asked, is the knocking synchronised in time with crankshaft revolution or much faster (likely camshaft ). Micky Edited March 1, 2017 by Motorsport Mickey Quote Link to post Share on other sites
stuart Posted March 1, 2017 Report Share Posted March 1, 2017 Had a tappet adjuster ball pierce the top of a pushrod once which picked the pushrod up and made a similar hammering noise. Stuart. Quote Link to post Share on other sites
DaveN Posted March 1, 2017 Report Share Posted March 1, 2017 Get a 0.010 feeler gauge and slide it between each rocker and valve with the engine running. See if the noise changes.. Quote Link to post Share on other sites
GT6M Posted March 1, 2017 Report Share Posted March 1, 2017 (edited) 1, yer rocker gaskets compressed, lett,n rockers hit the cover any tell tale mark ont inside 2, slack tappet, , esp if they worn, as will be set to wrong figs 3,cam follower gon already, this,ll show uo as a loose tappet too 4, a spark plug has got loose between the housing an procelane Butt, they still fire, !!! 5, ye had valve inserts fitted, is one coming loose, wont be a first with that !! M Edited March 1, 2017 by GT6M Quote Link to post Share on other sites
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