I have recently bought a daewoo nexia 1.5l twin cam 16v (looks like old astra but with isuzu engine apparently). Its only done 58000 miles.
After 2 weeks of driving it, it cut out while accelarating at 40mph, the engine warning light came on, and after pulling over and inspecting I found a breather (PCV) hose to be split open and the engine almost bare of oil. I cut the hose shorter and stuck it back in and refilled the engine with oil.
When I purchased the car, the oil level was on max, however there is no visible signs of a leak on the engine block and never any oil on the ground when left overnight, so it must be burning it. I did think it was a little smokey when first starting up but I stupidly ignored it.
I have cleaned all my PCV hoses which were very very oily and gunked up. I couldnt clean one hard to reach hose that comes into the camshaft cover from underneath the intake manifold ( I think its coming from the crankcase ). I also replaced the split PCV hose with a new one.
I have sought advice on the matter from a professional mechanic who said it was probably worn valve oil seals. Research on the internet and in this newsgroup confirms that bad valve oil seals could well be my problem.
Strangely, the oil doesnt seem to leak in a steady manner. I can drive around happily all weekend with no noticable oil loss but one journey to work (25 miles) can cause 1/4 - 1/2 litre to disappear. Just for the record its currently going through about 1 litre of oil every
250-300 miles !!I am a very keen DIY'er and love working on cars and I am thinking of refitting the valve oil seals myself. I know I need some fairly specialist tools like the valve spring compressor and an air pump thing to stop the valves falling in the combustion chambers. My only concern is its impossible to get Daewoo workshop manuals. They just dont exist, except in korean.
I am wondering:
a) if its worth buying a compression tester and running some tests before tackling valve seals. As I understand a low compression reading for both a dry and a wet compression test will confirm a possible valve oil seal problem.
b) if I should attempt to take off the intake manifold so I can get to the hard to reach PCV hose and clean that ??
c) if I should risk a valve oil seal replacement job without a manual, I have a Haynes for the vauxhall Astra which has a "similar" DOHC engine.
d) if I should just sell the car (I have a moral dilemma selling car on that has oil leaks though)
e) if there are any other possibilities about the cause of such a drastic oil leak ??
SORRY for the length of this message and thanks to anyone who has stuck with it this far :)
Any comments, ideas, advice is most greatly appreciated.
Thanks, An eager DIY car mechanic, mark