Weird oil burning problem

[500bhp]

I really need some help with this, my Disco is the 2 ltr petol version, and it has a weird problem with smoking badly on the over run of the engine. On throttle its fine but foot of say going down hill it smokes really bad, it would put James Bonds smoke screen to shame. The head has been rebuilt, compression seems fine, non of the engine oil breathers that go into the inlet manifold seem to have oil in them. so I am stumped any ideas ???????????.........Help

[waveydavey]

Not an engine I am that familiar with but it could be worth checking out the fuel injectors. If Petrol is leaking past them it could be burning without air. Put it on load and it gets the air and proper atomisation to burn.

[500bhp]

The problem is the same if it runs on petrol or gas, its definitely oil burning as the level is dropping on the dipstick....but thanks for the suggestion

[beast5680]

sounds like it is dragging oil down the valve stems on overun? i dont know the engine but i have seen this happen on others

[muddysteve]

i'd go for valve stem seals too

may even be worn valve guides


Steve

[500bhp]

I thought it may be the stem oil seals, but its just had a fully reconed head fitted ????????????

[Range Rover Blues]

So either it was done badly or it's the rings that have gone, particularly the oil ring.  The higher vacuum on overun is what's causing it.  If the engine is worn enough to need a new head, time for a compression test.

[500bhp]

Did the compression test and getting 245 to 250 lbs per sq inch on each cylinder??????????

[Range Rover Blues]

Then I'm going to agree with the others and say it's the valve stem seals, the fact that it's just had a new head makes it more likely.  Tell us, did it do it before the head was replaced?

[Damonski]

Havent come across that with mine ;)  But Im still having the occasional problem with high rev's about 1000-1200 as an idle speed and very rarely idling properly below 1000.

Think its getting ready for a service tho, first start of the day it sounds like a motorboat and is a right PIA to drive until its warmed up.

[imspanners]

Havent come across that with mine ;)  But Im still having the occasional problem with high rev's about 1000-1200 as an idle speed and very rarely idling properly below 1000.

Think its getting ready for a service tho, first start of the day it sounds like a motorboat and is a right PIA to drive until its warmed up.

The cold start issue will probably be sticking valves.
I'd recommend an oil flush, oil & filter change and using some Ecotek Power Boost Cleaner.

[ben_haynes]

Havent come across that with mine ;)  But Im still having the occasional problem with high rev's about 1000-1200 as an idle speed and very rarely idling properly below 1000.

Think its getting ready for a service tho, first start of the day it sounds like a motorboat and is a right PIA to drive until its warmed up.

My mums does the same thing it sound like a tank and clatters first thing wakes me up though :lol:

[Damonski]

Havent come across that with mine ;)  But Im still having the occasional problem with high rev's about 1000-1200 as an idle speed and very rarely idling properly below 1000.

Think its getting ready for a service tho, first start of the day it sounds like a motorboat and is a right PIA to drive until its warmed up.

My mums does the same thing it sound like a tank and clatters first thing wakes me up though :lol:

Yes!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Range Rover Blues]

For that I'd say check your idle bypass valve, but I don't know much about the MPi.