02 2.0 Oil Burning 2.0l Durateq HE - tonymuso
Hi all. My petrol Mondeo which I got cheap a few years ago, is now starting to burn oil at the rate of about 1 litre per 1000 miles. I know it was an ex-lease vehicle and servicing had been neglected, which is why I got it cheap. I bought it at 74k miles, and it now has 105k on the clock. At the last MOT in the summer, I had to have a new catalytic converter fitted + HEGO sensor, at a cost of £450 inc. diagnostics. I recently checked the spark plugs, and with the exception of the plug in no. 3 cylinder, all were oily around the tops of the threads near the plug body. I should say that the car is performing as well as it always has, and if I wasn't looking after it myself, I wouldn't know from the performance that anything was wrong; no misfiring, no lumpy idle etc.
I am contemplating an overhaul of the top end and have a couple of questions:
1. From this info, is it possible for any of you to say if the most likely cause of oil ingress to the combustion chambers is top down (valve stem seals perhaps), or bottom end up (piston rings perhaps), or could it be both?
2. If I do nothing and keep putting oil in it, how long before the oil burning wrecks the new catalytic converter? (We do about 10k miles a year)

thanks in advance........any comments welcome about the overhaul too.
02 2.0 Oil Burning 2.0l Durateq HE - cheddar
A couple of thoughts:

I think I have heard that burning oil is likely to be the valve guide seals on this engine, someone will confirm.

Some manufacturers, though not Ford, state 1ltr/1000 miles as normal oil consumption hence I would think that it should not damage a cat.

It might be that you could source a low mileage replacment engine for less than the cost of a top end job.
02 2.0 Oil Burning 2.0l Durateq HE - elekie&a/c doctor
High oil consumption on these Duratec engines is usually caused by oil control piston ring problems.Can sometimes be cured by an engine oil flush and refill with good quality oil.hth
02 2.0 Oil Burning 2.0l Durateq HE - tonymuso
thanks for the info. One mechanic told me not to use engine flush on an engine that's had oil changes neglected. He said the gunge that gets flushed down tends to gollect on the gauze at the top of the sump, and can then prevent the good oil getting pumped round the engine. what do you think?
cheers again
02 2.0 Oil Burning 2.0l Durateq HE - tonymuso
P.S. I should say that with the exception of the first year of my ownership, and 12k miles, I've changed the oil and filter every 6k, and usually use synthetic 5W 30
02 2.0 Oil Burning 2.0l Durateq HE - kithmo
If the valve guide seals are leaking, you'll get a puff of blue smoke on acceleration after overrun, if not then suspect the rings
02 2.0 Oil Burning 2.0l Durateq HE - tonymuso
thanks kith for that detail......I'll follow my wife in the car and check for smoke. Presumably the cat wouldn't deal with the blue smoke then?

Value my car