The Fiesta is holding out OK for my newly qualified 17yo. The car has been "in the family" since it was a year old, it's basically sound and I've spent quite a bit on fixing stuff rather than letting it go... So I want to keep it not change it. It's got somewhere around 50k (genuine) miles on it now.
Now, to the point. It is starting to guzzle oil, like a pint or so per 200 miles (maybe less). It isn't dripping out underneath so it must be burning it. I haven't looked too hard yet but I hadn't noticed clouds of black smoke when daughter pulls away. During elder daughter's ownership, it was run pretty dry of oil once. There is no oil in water, no water in oil as far as I can tell - head gasket was done about 2 years ago (3 maybe).
What is the problem likely to be and how can I verify what it is?
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valve seals dry up on these and crack,which is probably where the oil is going ie bypassing the seals into combustion chamber.they can be sorted without removing head using a tool to hold valve in place..presume you mean the OHV engine
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Steve
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valve seals dry up on these and crack,which is probably where the oil is going ie bypassing the seals into combustion chamber.they can be sorted without removing head using a tool to hold valve in place..presume you mean the OHV engine
Shows up as blue smoke on the overun, ie lifting off the throttle
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It might be worth checking the compression on cylinders to eliminate any bore wear. A quick way would be to use a socket on the bottom pulley and turn the engine over feeling the compression if it is healthy. Spark plugs may indicate health or otherwise if covered in oily deposits. Have you checked the breather in the oil filler cap? It could be coked up with carbon and causing some kind of breather problem affecting oil consumption. Last resort would be the valves and seals. I have done this job before on the MK2 Fiesta engine and with it being pushrod it's just patience and careful work needed to remove the head, take out the valves, clean them up and fit with new seals that come with the head gasket set. Worst part is removing the exhaust manifold due to rusted up nuts on the studs and cleaning up the studs to accept the manifold on re-assembly. They are pretty tough engines but I suspect that after a while they need a top end overhaul to restore compression and reduce oil consumption. If you remove the rocker cover often a lot of oil has carbonated and encrusted the valve gear. Once cleaned up always wise to keep to 6000 mile oil changes and use the 10/30 Ford oil.
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My 1.1 Fiesta started using oil at 110,000 miles but I fitted a new set of std. rings and the engine was still running well when I sold the car with 157,000 on it.I used Ford 20w/50 in the summer and 10w/30 in the winter.Incidentally Wilko's have 20w/50 for £2 for 4.5 lt.
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To do the valve seals on this engine, in the past, I have used string to hold the valves shut.
Slacken off all of the rockers - take the pushrods out if you can, to allow the rockers to be rotated right out of the way.
Take out the plugs, and then, one cylinder at a time, feed a fair amount of string into the cylinder, leaving some to pull out again afterwards. Then, by hand turn the engine until the piston jams up against the string in the cylinder. The string then prevents the valves of that cylinder opening.
Then, using an OHC valve spring compressor (these used to be popular for engines like the Ford pinto), or other appropriate levers, compress the valve spring, and remove the collets.
As you begin to compress the spring, keep an eye on the valve. If it shows any sign of moving, stop, and re-stuff the cylinder with string.
Fit the new oil seal, reassemble, and move on to the next valve.
This method avoids the need to disturb the cylinder head, and the hassle of separating the exhaust.
Number_Cruncher
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The string idea is interesting, but it might be a good idea to bite the bullet and just give it a good decoke.
I always used to do this on old simple carb engines. Push rods are even easier. There is no substitute for cleaning up all the black carbon that will be on an old but low milage car. Soak the exhaust studs in penetrating fluid 5-6 times, and overnight, for as long as you can. Put the valves in a drill and spin off the carbon. Once cleaned up, polished, and ground in, the car will be a much better starter, and will be more economic and smoother. Other benifits from an old fashioned decoke are no future head gasket problems, and all new tight gaskets. The whole job should take a long day. The head gasket set probably about £30+. A week later when all has bedded down and any muck flushed around, change the oil and filter, and have a good flush out (therostat out/remember the set usually comes with a new gasket) and new antifreeze. In the end the time saved over the string approach is probabaly 4-5 hours. But the satisfaction of a good decoke is immeasurable.
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>>The string idea is interesting,
though I did not mention it,Number-Cruncher did it the same as me.But with petrol as good as it is now/engine oil,I see no reason to give a full Decoke,if this is neccesary then fair enough.but would be surprised if it was?
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Steve
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I know my car has dodgy valve stem seals - I can see the gasses blow-by in the rocker box, but it doesn't use as much as yours (unless it's the rings that are blowing). The only time it has done so is when the oil pressure switch leaked. How many miles does it do in a journey? I'm thinking the oil maybe dripping at the back and evaporating off a hot exhaust. Just a thought.
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Mike Farrow
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Mike,
Blow-by in the rocker box is usually an indicator of worn pistons/rings/bores rather than of defective valve stem oils leals. However, I'm not saying that your valve stem oil seals aren't past it either! :)
Number_Cruncher
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On a weekly basis it does 4 or 5 return journeys to college (< 5 miles) and a couple of returns Wokingham to Winchester - which I'd guess at 25 - 30 miles each way - per week. Plus local trips to friends/shops.
Still dithering over whether to fix or replace...
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Valve stem seals leak more when the engine is cold as they go hard;as the engine warms up they soften and seal better;that's why you often get a puff of smoke when you first start-up.At that mileage it's more likely to be pistns/bores-see my previous comment about rings.
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I've used the "rope trick" very successfully on a different car (Volvo), but the principle is the same - compressed string stops the valve from falling into the cylinder when the spring is released. Warning - make sure the crankshaft can't turn while you have the valve disconnected.
The little rubber seals are cheap, so it's worth a first shot surely? Combined with thorough cleaning of the external breather system, air intake etc.
You can do a certain amount of cleaning with a wooly recorder or bottle cleaning brush and carb cleaner through the spark plug hole. Then put cleaning additive through the petrol and give the engine a good blast.
If that fails, then time to think about bore/ring wear and the possible options.
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As I said it was just a thought :-)
I know I've got poor compression in one cylinder - the starter motor tells me so, but it doesn't use much oil over long journeys (say 1/2 litre in 3k miles), and not much more over short journeys, which is why I didn't think it was the bores. Emissions (non-catalysed) are 0.31% CO and 384ppm HC.
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Mike Farrow
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Check down the back of the engine, where the coil pack fastens to the block. This a notorious place for oil leaks on this engine. The oil leaks down the back and drips on to the exhaust/CAT and burns off, so you don't see any oil on the floor.
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