Dazzled Posted July 27, 2012 Share Posted July 27, 2012 Last weekend i noticed a drop of oil on the garage floor under the exhaust. Its a 4 2 1 exhaust and the oil was under the cat by pass pipe. I've just started the car up to check and there is indeed oil trickling out of No2 down pipe and fair degree of oily smoke. Its an ex VVC K series with a DVA conversion and has done about 16,000 miles with circ 4k since Dave Andrews breathed on it. Obviously any oily smoke is never a good sign. Views on what might be the cause? Dave Link to comment Share on other sites More sharing options...
john milner Posted July 27, 2012 Share Posted July 27, 2012 If it is oil and not water/petrol & soot then I would have thought it is most likely worn piston rings or cylinder bore. Link to comment Share on other sites More sharing options...
Bio Posted July 27, 2012 Share Posted July 27, 2012 Does it use any oil on a run when warm....Could be a worn valve stem seal leaking oil past the exhaust valves when not in use. This would cause smoke on start up and after a period at idle. Do the plugs look oily 🤔 Link to comment Share on other sites More sharing options...
Dazzled Posted July 28, 2012 Author Share Posted July 28, 2012 Its most definitely oil and not petrol/ water and its not got a history of using oil on a run - and its done some big mileages in a day. It has been sitting idle for quite a while - and by quite a while i mean a shameful 8 months. Dave Link to comment Share on other sites More sharing options...
Mark Chilton Posted July 28, 2012 Share Posted July 28, 2012 Dave, YHM Link to comment Share on other sites More sharing options...
oilyhands Posted July 28, 2012 Share Posted July 28, 2012 I have been examining this problem on a couple of other engines. The problem only seems to occur on cylinder 2 & 3 and on careful scrutiny of the head castings, the oil drainage from this area of the head around the base of the valve guides/stem seals is not very good, it is fine on cylinders 1 & 4 as there are drainage grooves to allow excess oil to escape down the bolt hole drains, on 2&3 these drainage grooves are not present so oil accumulates in this area. When the engine is installed in a Caterham the angle of the engine is such that a fair bit of oil can accumulate and submerge the ends of the guides of cylinder 2&3 in oil on a permanent basis. If the engine is left for any period of time oil can seep slowly past the stem seal (especially if the valve is open) and down the guide into the exhaust port. The excess oil will also give the stem seals a hard time while the engine is running. If you dont have a 4-2-1 exhaust or similar the oil will probably not makes is presence felt, if you do, some will leak from the joins and alert you to the issue. I am progressing a solution which establishes oil drainage holes for cylinder 2 & 3 at the base of the guide platform which should eradicate the problem which is only prevalent on VVC heads. Oily Link to comment Share on other sites More sharing options...
Dazzled Posted July 30, 2012 Author Share Posted July 30, 2012 Hi Oily , Thanks for the details. It exactly describes my issue. I guess there is no point in getting the valve seal replaced without having the root cause fixed too. I'll be in touch separately about that. Given that the car needs an MOT I doubt it'll pass the emissions test in its current state. Dave PS - John A loves his Elise now that you've tweaked it. He's out terrorising the commuters of MK. Link to comment Share on other sites More sharing options...
Grim Reaper Posted February 9, 2014 Share Posted February 9, 2014 Was there a solution to this oil retention problem? I have my head in bits at the moment so can drill holes where necessary if it's as simple as that. Link to comment Share on other sites More sharing options...
oilyhands Posted February 9, 2014 Share Posted February 9, 2014 The drainage holes are require In the corners of the spring seats and must cut through to the bolt hole drains, you cannot drill, the angle required means that a circular carbide burr is required and must be moved sideways to make the hole. It is effective though.. Oily Link to comment Share on other sites More sharing options...
Grim Reaper Posted February 10, 2014 Share Posted February 10, 2014 Ah, I think I know where you mean,I'll have a look when I get the springs out Link to comment Share on other sites More sharing options...
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