Grubbster Posted December 4, 2011 Share Posted December 4, 2011 Engine is a high powered K. I last used the car in anger on a trackday in October but didn't notice anything odd on the day. As it runs solid followers it does sound quite 'tappety' particularly when cold but normally sounds OK once warm. Today though it sounds like 1 follower is always noisy even when warm. I've checked the easy things that I am aware of (oil level, spark plugs are done up, exhaust manifold bolts are tight). Just wondering what else I can easily check myself? If I take the cam cover off is there much I could see? It has solid followers and double valve springs so I wonder if there could be anything amiss there? Link to comment Share on other sites More sharing options...
oilyhands Posted December 4, 2011 Share Posted December 4, 2011 Remove the cam cover and check your clearances with a feeler gauge. For each lobe of the cams, turn the engine over by hand until the lobe is pointing up and away from the follower. Then use succe4ssively thicker feeler gauges to see what the gap for each lobe/follower is. Depending on cam profile they are either 10thou inlet/12thou exhaust , or 8/10. If any of the foloower gaps are more than 3 thou over they could be the source of the tapping. If any of the follower tops or cam lobes look different (not smooth) from the others then that could be your problem. Oily Link to comment Share on other sites More sharing options...
Grubbster Posted December 4, 2011 Author Share Posted December 4, 2011 Thanks Dave, I just took the cam cover off, nothing obviously different about any of the lobes so I'll get the feeler gauges out and report back later Link to comment Share on other sites More sharing options...
Grubbster Posted December 4, 2011 Author Share Posted December 4, 2011 OK, here's the news: Exhaust side = 10 9 9 9 9 9 7.5 8 Inlet side = 8 7 7 8 8 6 18 9 So I assume that 18 on the inlet is way too much and probably the cause of the tapping sound. Now I have to work out what could have changed to make it like this? Pretty sure it hasn't always made this noise so something has happened. I guess it's time to take it to someone to have a look at ☹️ Link to comment Share on other sites More sharing options...
oilyhands Posted December 4, 2011 Share Posted December 4, 2011 It's quite well known that often the VHPD shims are insufficiently hard to withstand the hammering they receive from stronger springs and more aggressive cams. Sometimes the hardening is unsufficiently thick too so the slightest adjustment to their thicknes results in carving through to softer material. I expect it will reveal a hammered shim, or of course it could be a bent valve... eeeek. There are a couple of tight ones too that need addressing. It's a ballaching job to do with the head fitted, but emminently possible. I've done a dozen or so tappy engines that way. Oily Link to comment Share on other sites More sharing options...
rj Posted December 4, 2011 Share Posted December 4, 2011 Oily, If the OEM shims are not good enough, where do you recommend getting them from? Link to comment Share on other sites More sharing options...
Grubbster Posted December 4, 2011 Author Share Posted December 4, 2011 Thanks Dave, 18 thou - was the last one I measured so I didn't think I was going to find a worn one. I'll have to get it sorted before using it I guess so no trackday for me on Saturday 10th after all ☹️ Link to comment Share on other sites More sharing options...
oilyhands Posted December 4, 2011 Share Posted December 4, 2011 I expect there are other soruces, but I have them made from silver steel which is through hardened. Oily Link to comment Share on other sites More sharing options...
Grubbster Posted December 11, 2011 Author Share Posted December 11, 2011 I took it in to New Techniques yesterday so it'll be sorted soon. We had a quick look at the valves with an endoscope (another great gadget to add to the wish list!) and they look fine and seated correctly so hopefully it is just a case of a duff shim. Link to comment Share on other sites More sharing options...
ECR Posted December 11, 2011 Share Posted December 11, 2011 Stop worrying and get back in the Elise Link to comment Share on other sites More sharing options...
Grubbster Posted December 11, 2011 Author Share Posted December 11, 2011 SWMBO is very pleased with the Elise - driving it makes her realise how much she really hates my Caterham 😬 Link to comment Share on other sites More sharing options...
zetec Posted December 11, 2011 Share Posted December 11, 2011 Sorry to hear this Grubs ☹️ I hope its not serious & fixed quickly for you, Mine gunna be out for a while due to engine & gearbox & diff change in jan/feb/mar Link to comment Share on other sites More sharing options...
Grubbster Posted December 11, 2011 Author Share Posted December 11, 2011 Cheers Zetec, I'm sure it'll be fine soon. It did get a fair old hammering at the last trackday and it is a bit highly strung so I expect to need a bit of work on it every now and again. Looks like we're going for a breakfast blat in the Elise with SELOC next Sunday, brekkie at 10:30 - a much more civilised time than we normally go for in the 7! Link to comment Share on other sites More sharing options...
zetec Posted December 12, 2011 Share Posted December 12, 2011 If we didnt need four seats id get an elise tomorrow, love them almost as much as a seven! Link to comment Share on other sites More sharing options...
Grubbster Posted December 21, 2011 Author Share Posted December 21, 2011 Update time - the problem is that one of the followers has worn on the top so it is now slightly 'dished', this has also caused the cam to wear. So I need a new camshaft and rather than change 1 follower I'm having the lot replaced as it seems like false economy to do just the one. Sadly it won't be sorted this side of Christmas ☹️ Link to comment Share on other sites More sharing options...
Andy Whittle Posted December 21, 2011 Share Posted December 21, 2011 Oily fixed mine for me in a 1.9K. There were 3 that were very worn. http://img.photobucket.com/albums/v185/Whittler/IMG_0433.jpg It took a long time to do, Oily's patience is amazing Edited by - Andy Whittle on 21 Dec 2011 23:00:18 Link to comment Share on other sites More sharing options...
Ray Pearce Posted December 22, 2011 Share Posted December 22, 2011 Ouch! Are those just depressions or has it worn right through the crown of the follower? Link to comment Share on other sites More sharing options...
Andy Whittle Posted December 22, 2011 Share Posted December 22, 2011 They are just the depressions in the not-so-hard tiny shims; they are about 10mm in diameter. The followers and cams were still good. Oily measured each one about 5 times, selecting the correct one to get the gap right and gently grinding some to fit. Of course there are 16 to sort out 😬 Link to comment Share on other sites More sharing options...
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