Not calibra related but help needed please!!

[skitz_1184]

I have an astra mk4 1.6 16v which i use as a family car (used to use the calibra but two doors is a pain in the *** and kids destroy cars!! ) and there is mayo on the dipstick and on the oil cap. This would normally send alarm bells ringing as i would normally assume it would be the head gasket but..................

The strange part is that it does not overheat at all. even if i drive it like i stole it, in fact the temp guage only reaches around a quarter of the way up the gauge. Its not using any water at all.

Me and a mate of mine rebuilt the engine with a new head gasket, new valve stem seals and cam seals last september time and since then it has burnt oil on cold startup and will also run like a pile of toilet until warm but once warm (or after a few minutes of running) its is fine. no more burning oil and runing like a dream.

I assumed the oil burning when cold would be worn valve guides?

I have no idea why it runs like a pile of toilet when cold? perhaps its because its got a decat pipe on it? (i have a standard exhaust for it)

and the mayo............. was told this can happen when cheap oil (which i used cause mine was burning so much lol) is used and cars only make short journeys (which mine does)

i have tested compression and i believe it was 150 across all four so compression is fine, it definatley doesnt seem down on power. i read that a broken thermostat may cause the mayo??

any opinions would be appreciated

[Fraz]

blocked breather and cheap oil ...and short trips all mean Mayo

[skitz_1184]

Blocked breather, that would make sense . i do recall bending the breather pipe while fitting the engine and having to bend it back to shape. perhaps i should replace it.

yopu think that could make the oil burning worse too?

[Fraz]

well I would also check the bit on the throttle body that the pipe goes to, as no doubt the hole to provided vacume will also be blocked, as will the bit on the other end of the pipe. I would replace the pipe or pipes and change the oil and put better oil in it ...cheap oil is usually recycled oil, and if its not getting to the correct temp it will be making things worse

blocked breather also means back pressure, so would not be helping

[Allys Cally]

this used to happen to our old astra g, as Fraz has pointed out cheap oil or mixing oils can result in the mayo. a good long run normally cures it.