Bald Rick Posted September 21, 2015 Report Share Posted September 21, 2015 Hi folks Having spent a bloody fortune having my TR6 rebuilt on a new chassis (and a superb job it was too) I was looking forward to a few years trouble free motoring around Europe. And it did seem like my dream would be realised until this little knock started. I became paranoid about this knock. I could hear it whenever I went out in the car. I asked friends “What do you think that knock is?” “What knock?” was the usual answer. I was sure it was getting louder, I took it to a local classic car specialist who drove it several miles. “Just sound like a TR6 to me” he said, adding “I thought it was rather quiet actually.” By this time I was totally convinced the engine was destroying itself so I drove it into the garage and left it there. I managed at one stage to convince Andrew Smith that it was knocking and he kindly arranged for another specialist to check it out. He came out with some excellent suggestions but I wasn't convinced. The TR has now languished in the garage for some time. It did 39 miles between the last two MOTs that mostly being to try and convince various victims. “Can you hear the knock?” I would ask as I wound it up to 6000 rpm through the gears. But enough is enough. It needs to be sorted I decided to drain the oil and change the filter again and then decide what to do. So any suggestions, advice, witticisms, insults from the forum would be much appreciated. The engine was scratch built using a NOS crank. The flywheel was lightened and the whole crank, flywheel, clutch and damper assembly was balanced. A CP block was aquired and re-bored (only +.020) and chemically cleaned, new pistons, new timing chain and sprockets, stage 2 head, camshaft and followers from Chris Witor along with a blue printed oil pump. Shell bearings from ACL. Custon built distributor. I was the engine builder. The aim was not to build a fast car but one that pulls steadily throughout the rev. range. The knock is mostly heard as the engine comes under load, as I engage the clutch. It is a light knock and is at engine speed. It does not occur on over run, so I assume it is not a little end. It is not a big end type knock or a main bearing rumble. Oil pressure is excellent, dropping to about 30 on tickover (which is very lumpy but slow) the engine does not overheat. So last Saturday I got some help and we drained the sump. The oil was still clean (translucent) but, for the first time the sump plug resembled a Christmas tree. http:// Although not happy, I feel vindicated, something created those metal filings! But What? My thoughts now are that it may be camshaft failure, So I am planning to have the head off as a first step. Your thoughts and suggestions would be most welcome. Cheers Tony Quote Link to post Share on other sites
Andrew Smith Posted September 21, 2015 Report Share Posted September 21, 2015 Ok mate, now I'm convinced - but I still swear I couldn't hear anything! I think you're shaving the lobes off the camshaft! Cheers Andrew Quote Link to post Share on other sites
foster461 Posted September 21, 2015 Report Share Posted September 21, 2015 Tony, it sounds like you are on the right path to pull the head and I would also pull the sump off and then get a look at the crank, bearings, oil pump and with the head off have a look at the lifters and the cam lobes. My TR6 has also developed a tapping/knocking noise that I cant track down so I may be following your example soon. Repro cams and lifters have all had their issues over the years due to poor hardening so that is a very likely culprit and should be easy to spot with the head off. Stan Quote Link to post Share on other sites
Tom Fremont Posted September 21, 2015 Report Share Posted September 21, 2015 Hi Tony, A load-sensitive knock doesn't seem like a valve train issue to me. I've had cams lose lobes and they weren't load sensitive; moreover they sounded more like rattling as if the lash got very loose. For what it's worth my driver's engine has 110K miles and 20 years with a knock for the entire duration. It is not load sensitive and is most pronounced when the engine has slightly cooled but still warm. When fully hot it is quiet and likewise when cold. As in your case, others don't hear it. It is audible to me between 1500 and 2000 rpm and silent otherwise ( well, for a TR ). Oil pressure is at the maximum factory specified value of 65 psi @ 2000 rpm when hot hot hot ( does have an oil cooler ). I would check the end float ( if you haven't already ) and drive it some more. The shavings on your magnetic plug may be typical for a new engine. Cheers, Tom Quote Link to post Share on other sites
Guest ntc Posted September 21, 2015 Report Share Posted September 21, 2015 Tony Clean the bits carefully to check the colour and report back. Quote Link to post Share on other sites
RogerH Posted September 21, 2015 Report Share Posted September 21, 2015 Hi Tony, did you filter the oil through a filter paper. The magnetic plug only gets the steel. Is there any bronze/brass/chrome plate etc. Roger Quote Link to post Share on other sites
Peter Cobbold Posted September 21, 2015 Report Share Posted September 21, 2015 (edited) I too doubt its cam wear, and if it were measuring valve lifts should reveal it ( before lifting the head). My suggestion is put it on a rolling road and explore for the source with a stethoscope. Put it on the PI MU first of all, that can make a light tapping, and as the load comes on the fuel delivery will rise in step, so it could be load sensitive. To me it was more of a subdued tap than a knock, and rose with rpm. Peter Edited September 21, 2015 by Peter Cobbold Quote Link to post Share on other sites
stuart Posted September 22, 2015 Report Share Posted September 22, 2015 I too doubt its cam wear, and if it were measuring valve lifts should reveal it ( before lifting the head). My suggestion is put it on a rolling road and explore for the source with a stethoscope. Put it on the PI MU first of all, that can make a light tapping, and as the load comes on the fuel delivery will rise in step, so it could be load sensitive. To me it was more of a subdued tap than a knock, and rose with rpm. Peter Peter its a carb engine with engine driven fuel pump. Stuart. Quote Link to post Share on other sites
roy53 Posted September 22, 2015 Report Share Posted September 22, 2015 Tony is the first oil after the restart of the new engine ? Had simlar issues once , turned out to be rev counter related.cannot remember if it was the cable or the clock but was changing rockershafts etc to try to eliminate .Would describe mine as more of a tick though rather than a knock. Roy Quote Link to post Share on other sites
Blue cedar Posted September 23, 2015 Report Share Posted September 23, 2015 Tony. If this is the first oil change, perhaps it is Cr-p from the engine, not fully cleaned. Surely, if the noise isn't getting worse you should just drive it 500 miles and remove the sump plug, plugging the hole with your thumb, so you don't loose too much oil, and if there is no debris , put the sump plug back in place. We need to remember these are noisy engines, partly because of the generous tolerances and age design. Be careful, we can tend to compare against our modern car engines, which are silky smooth with very small tolerances, hence very quiet. Sometimes best to accept what you have.......a 50 year old design engine, with a noise no one else can hear and carry on enjoying the car. Best of luck Peter Quote Link to post Share on other sites
stuart Posted September 23, 2015 Report Share Posted September 23, 2015 The engine was rebuilt a few years ago and has been hard driven. Stuart. Quote Link to post Share on other sites
Blue cedar Posted September 23, 2015 Report Share Posted September 23, 2015 Stuart......so it isn't unreasonable to expect that "driven hard" is the cause and the collection of mental the resulting symptom !!!! Quote Link to post Share on other sites
Andrew Smith Posted September 23, 2015 Report Share Posted September 23, 2015 It's not driven THAT hard as it would frighten Baldrick! Quote Link to post Share on other sites
stuart Posted September 23, 2015 Report Share Posted September 23, 2015 True but he does like to push that red line! Stuart. Quote Link to post Share on other sites
Alec Pringle Posted September 23, 2015 Report Share Posted September 23, 2015 You mean he's finally noticed the red line . . . . . ? Does he know what it's for . . . . . ? Cheers Alec Quote Link to post Share on other sites
Blue cedar Posted September 24, 2015 Report Share Posted September 24, 2015 When I was a child at the funfair, if you could hit the red area you won a bag of sweets or a teddy . Perhaps An element of reliving our youth, without knowing it ? Quote Link to post Share on other sites
littlejim Posted September 24, 2015 Report Share Posted September 24, 2015 It's not driven THAT hard as it would frighten Baldrick! Bull! His overtaking maneuvre to catch up to you on our burn, was foot-to-the floor neck-snapping stuff. The only knocking sound that day was my knees. Engine revs drowned that out. Quote Link to post Share on other sites
Andrew Smith Posted September 24, 2015 Report Share Posted September 24, 2015 Bull! His overtaking maneuvre to catch up to you on our burn, was foot-to-the floor neck-snapping stuff. The only knocking sound that day was my knees. Engine revs drowned that out. True Jim, but I guess he had to drive like that to catch up with a CP TR6................ Cheers Andrew Quote Link to post Share on other sites
steve26 Posted September 24, 2015 Report Share Posted September 24, 2015 Hi Tony, I too recently had a knocking on my TR3A. As yours, it occurred only under load. I had recently fitted new points, rotor arm and distributor cover. It was also apparently not heard by others or dismissed as normal. It was then suggested to me that it could be 'pinking'. and that I should reset the static timing (using light bulb and wire). Then advance the timing as per the book. This I did and Bingo - right first time. Seems I must have disturbed the setting, possibly due to the clamp not being tight enough. I realise this would not explain your 'Christmas tree plug, but surely worth a try. Regards Steve Quote Link to post Share on other sites
Red 6 Posted September 24, 2015 Report Share Posted September 24, 2015 Before you start whipping it all apart I suggest, as have others, that you give everything the once over with a stethoscope to isolate the bits which either causing the knock or just as important not causing the knock. If you are anywhere near me in N London I would be happy to assist as I have a stethoscope and know how to use it! Quote Link to post Share on other sites
Bald Rick Posted September 28, 2015 Author Report Share Posted September 28, 2015 Hi Folks Thanks for all your replies. I apologise for not responding sooner but I've had a few domestic issues to deal with over the last couple of weeks which have taken up a lot of my time. Hopefully they will be resolved this week and I can get back to the TR6. I will also go through the paperwork and see if I can provide a history of the engine. Thanks again for your replies. Tony Quote Link to post Share on other sites
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