Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - John F

Our almost worthless but excellent Focus will soon need an oil change at 125,000m. So far I have used a cheap semi-synthetic recommended 5-30 every 10-12,000m or so. It only does about 8,000m a year. However, it is now using around one litre every 5,000m which is reasonable. But I think for a loose worn engine 5-40 or even 10-40 might be more suitable (it has no turbo or chain to lubricate). There does seem to be a body of opinion on USA sites that supports this idea. What do the pundits here think?

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - skidpan

Our almost worthless but excellent Focus will soon need an oil change at 125,000m. So far I have used a cheap semi-synthetic recommended 5-30 every 10-12,000m or so. It only does about 8,000m a year. However, it is now using around one litre every 5,000m which is reasonable. But I think for a loose worn engine 5-40 or even 10-40 might be more suitable (it has no turbo or chain to lubricate). There does seem to be a body of opinion on USA sites that supports this idea. What do the pundits here think?

Definitely not. A thicker oil takes more pumping and a car with 125,000 miles on the clock will have a worn oil pump that may struggle. Thicker oils take longer to get around the engine accelerating wear.

Ford specify 5w30 after extensive testing, they know a thing or two about engines.

IIgnore Americans, they are idiots, just look at the president they elected.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - RT

No - don't use thicker oil - use the recommended viscosity and ACEA grade - find the cheapest that meets that specification and put up with the consumption.

Car makers don't accept a problem with an engine unless consumption is worse than 1,000 miles/litre - at 5,000 miles/litre you're not even close.

As said ignore Americans - they typically use low quality mineral oil, changed very often, not the much higher specification oil used in Europe - their practice in their culture is ok, but not here.

Edited by RT on 15/06/2017 at 19:40

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - kiss (keep it simple)

If you have been changing the oil regularly there is probably no appreciable wear on the engine, it's old but not worn at 5000 miles per litre.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - Tester

Slightly off-topic, but am I alone in feeling that 1000 miles per litre of oil is extraordinarily high to be 'acceptable' - or have I just been lucky? My ancient Citroen 2.2 diesel (15 years and still going nicely) has never used any noticeable amount of oil between changes at the shorter of 1 year/10,000 mile intervals, always using the correct synthetic oil. I do check the dipstick periodically because things might change but it has been reassuringly predictable so far. What is the experience of others?

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - Andrew-T

Slightly off-topic, but am I alone in feeling that 1000 miles per litre of oil is extraordinarily high to be 'acceptable' - or have I just been lucky?

That depends on what you personally will 'accept', and on the route by which the oil is disappearing. In my much younger days the Morris 1100 I drove in Canada and the US was losing oil faster than petrol (meaning I stopped for it more often) but the cost of curing the problem was a lot more than that of the oil. Deciding acceptability simply on cost probably leads to the same conclusion today.

If the oil is being burnt, meaning a worn engine, that may foul up the cat quite quickly. If it's getting past valve stem seals, or simply leaking past a sump gasket, you may reach a different decision. I don't like dirty drips on the garage floor, for example, and I also prefer an engine where the oil doesn't drop from MAX to MIN on the dipstick between changes. As has been said here about MINI engines (for example) modern engine tolerances should be able almost to eliminate consumption of oil.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

To put off throwing stuff out, which I hate, I'll have crack at the "thin v. thick" chestnut.

This is an oldie but mouldy, and, like many basic automotive questions, hard information on it is rare, but as a generalisation the above "Thin gooood, Thick baaaad" concensus is simplistic and mostly wrong.

Firstly, the "American Culture" thang. This picture of American motorists as good ol' boys keen on duelling banjo's, chawin terbacca, 1957 Chevvies and thick mineral oil is attractive, but largely bogus. American motorists will probably generally follow the owners manual almost, but perhaps not quite, as uncritically as British motorists, and owners manuals designed for the American market generally insist on skinny oils, skinnier than the same car would specify for the Australian market, for example, where 20W50 is still commonly recommended and used.

This difference is probably largely due to the US government CAFE regulations, which impose "fleet" fuel economy targets (with associated penalties) on manufacturers.

Skinny oils give marginally better fuel econony due to the lower initial viscosity. I suspect wide range multigrades (say an 0W40 compared to a 15W40) may also give marginally better fuel economy at the final viscosity due to the temporary viscosity loss behaviour of viscosity improvers, but I can't remember if I've ever seen confirmation of that.

The tradeoff for this fuel economy benefit, is a lower level of protection. Lower viscosity oils give a lower minimum oil film thickness, and in locations where contact can routinely occur, like cam lobes and piston rings, they will spend less time in hydrodynamic lubrication, where it doesn't, and more time in mixed and boundary layer lubrication, where it does, amd where wear is limited by anti-wear agents and friction modifiers which coat the surfaces.

This does not mean that skinny oils give inadequate protection. Most cars are scrapped long before engine wear becomes an issue, and the tradeoff is probably entirely rational for the vast majority of new car purchasers. Nevertheless, the protection is better, and the oil consumption lower, for thicker oils. Since these generally use less VI's they also tend to be more resistant to shearing and less likely to gum up piston rings.

The usual counter argument is that thinner oils give better protection because they get to the top-end quicker and/or circulate faster. Most if not all oil pumps are "positive displacement" which means that, provided the pumpability limits of the oil is not exceeded in extreme low temperatures, they will deliver a fixed volume of oil per revolution, irrespective of oil viscosity. In practice there is some "leak back" of oil past the pump gears. This leakage increases with pump wear and decreases with oil viscosity, so a worn oil pump will deliver less skinny oil and generate a lower oil pressure with it.

For a given oil pressure, oil flow through an oilway will be greater with skinny oil, but this is unimportant, since flow doesn't lubricate. Flow removes heat and debris but these are not usually limiting factors.

Note that I'm generalising here. I know nothing specific to the Ford Zetec and am not saying you should put thicker oil in it.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - SLO76
Normally I'd agree John but the excellent Zetec SE is very oil specific and tends to deteriorate on thicker oil. I'd stick with what Ford recommend, it's worked well for you to date.
Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - Ian D
Stick with 5w30, when Wilko sell 5 litres of Mobil Super 3000X1 Fully Synthetic Motor Oil 5W30 for £24 there is point putting in anything else.
Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - John F

Thank you all for your opinions. I have just ordered 5 litres of W***o's own brand synthetic 5W30 on line for a bargain £16. It may not be top quality but will suffice for our low mileage need. The difference will provide well over a litre of plonk for the sangria to ameliorate the national mood this w/e....:-(

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - RT

Thank you all for your opinions. I have just ordered 5 litres of W***o's own brand synthetic 5W30 on line for a bargain £16. It may not be top quality but will suffice for our low mileage need. The difference will provide well over a litre of plonk for the sangria to ameliorate the national mood this w/e....:-(

As well as the correct 5W-30 viscosity, is it the right ACEA grade as that's just as important.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - John F

As well as the correct 5W-30 viscosity, is it the right ACEA grade as that's just as important.

It purports to be ACEA A5/B5 (only way to find it is google 'W****o fully synthetic motor oil'), and the blurb says 'suitable for....Zetec engines'. Seems a bargain to me. I think I'll give the Redex a miss as the oil consumption is not that high.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - Stanb Sevento

Just a thought john F, if you fancy giving this a try.

Stick 1/2 a bottle of Red-X down the plug holes when engine is hot and let it sit for a few hours. Turn the engine with a rag over the plug holes to soak up the liquid thats sprayed out. Restart and watch the black smoke for the first few seconds.

A lot of high mileage engines burn oil because the rings are stuck in their grooves with build up not because they are worn and good oldfashioned Red-X is actually very good at freeing them.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

Just a thought john F, if you fancy giving this a try.

Stick 1/2 a bottle of Red-X down the plug holes when engine is hot and let it sit for a few hours. Turn the engine with a rag over the plug holes to soak up the liquid thats sprayed out. Restart and watch the black smoke for the first few seconds.

A lot of high mileage engines burn oil because the rings are stuck in their grooves with build up not because they are worn and good oldfashioned Red-X is actually very good at freeing them.

Brake fluid is also used by some people for this.

I havn't tried it, but I've found it to be an effective carb cleaner, so it might work.

In either case (but especially the brake fluid) it might be best to schedule this before an oil change, in case any of it gets into your oil.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - skidpan

Just a thought john F, if you fancy giving this a try.

Stick 1/2 a bottle of Red-X down the plug holes when engine is hot and let it sit for a few hours. Turn the engine with a rag over the plug holes to soak up the liquid thats sprayed out. Restart and watch the black smoke for the first few seconds.

A lot of high mileage engines burn oil because the rings are stuck in their grooves with build up not because they are worn and good oldfashioned Red-X is actually very good at freeing them.

Brake fluid is also used by some people for this.

I havn't tried it, but I've found it to be an effective carb cleaner, so it might work.

In either case (but especially the brake fluid) it might be best to schedule this before an oil change, in case any of it gets into your oil.

Why not try some battery acid. That really cleans stuff.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - jc2

Don't know about Redex but most "upper cylinder lubricants" were a mixture of engine oil and paraffin-change the percentages of each and it was called "flushing oil"!

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - focussed

The OP says that the oil is changed at 10k - 12 k miles.

My experience of oil usage when doing starship mileage in company cars ie 1000 miles a week + is that the oil consumption is negligable for the first 5k to 6 k miles after an oil change, and then they start to use a bit of oil after that until the next oil change.

The reason is that the oil literally starts to wear out and that the stuff that holds the oil together is starting to let go and the oil thins out and hence the engine tends to use a little.

My advice is to reduce the oil change interval and see if that reduces the consumption.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - Manatee

The OP said consumption is 5000 miles per litre. That's not out of the way for an old worn engine. And half the oil is being changed between services anyway.

Don't those engines have hydraulic tappets ? I wouldn't mess with the oil spec unless I wanted to try and create another problem.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

Just a thought john F, if you fancy giving this a try.

Stick 1/2 a bottle of Red-X down the plug holes when engine is hot and let it sit for a few hours. Turn the engine with a rag over the plug holes to soak up the liquid thats sprayed out. Restart and watch the black smoke for the first few seconds.

A lot of high mileage engines burn oil because the rings are stuck in their grooves with build up not because they are worn and good oldfashioned Red-X is actually very good at freeing them.

Brake fluid is also used by some people for this.

I havn't tried it, but I've found it to be an effective carb cleaner, so it might work.

In either case (but especially the brake fluid) it might be best to schedule this before an oil change, in case any of it gets into your oil.

Why not try some battery acid. That really cleans stuff.

I think I'll leave the acid comments to you.

Why have a dog and bark yourself?

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

Water works pretty well as a decoke in a running engine, because in those conditions its quite an aggressive oxidant.

When I first got it my current car it was running-on after shutoff, and seemed to be suffering from pre-ignition at idle (or perhaps pre-ignition-induced detonation, if that happens, since there was an intermittent sharp tap.)

I ran an IV line into one of the many vacuum hoses around the 1980's carburretor and got it to suck about half a litre or so of water in at a fast idle and it stopped doing it. Should probably have been distilled water but I used aircon condensate which is probably close enough, and available here in unlimited quantities for free in the summer.

I should have rigged something to inhale a little water in normal operation, but I never got around to it.

Whether it would unstick rings (alone of in combination with other treatment) I don't know, but I don't see why not.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - John F

Water works pretty well as a decoke in a running engine, because in those conditions its quite an aggressive oxidant.

Wow - never heard of this procedure! Not sure of the chemistry here. Perhaps it just dissolves the carbon? What about adding some washing-up liquid as a detergent?!

Did you ever sort the coolant use - was it the head gasket?

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - skidpan

Water works pretty well as a decoke in a running engine,

I have never read such a total load of bull excrement. If some gullible people read this and tried it they could well total their engines.

Modern engines running the correct oil and any fuel that neets the current BS standards (that is any fuel sold in the UK) should never need a decoke.

Just drive your car and enjoy it and service it every year.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - focussed

Water works pretty well as a decoke in a running engine,

I have never read such a total load of bull excrement. If some gullible people read this and tried it they could well total their engines.

Modern engines running the correct oil and any fuel that neets the current BS standards (that is any fuel sold in the UK) should never need a decoke.

Just drive your car and enjoy it and service it every year.

Actually it's not as daft as it sounds, you can always tell when a diesel has been running with water in the fuel, or water mist getting into the air inlet.

The piston crowns will be bright instead of black and sooty.

Whether it makes any difference is another matter!

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

Water works pretty well as a decoke in a running engine, because in those conditions its quite an aggressive oxidant.

Wow - never heard of this procedure! Not sure of the chemistry here. Perhaps it just dissolves the carbon? What about adding some washing-up liquid as a detergent?!

Did you ever sort the coolant use - was it the head gasket?

Don't think detergent would make any difference.

At the high temperatures of the operating engine, the water dissociates into oxygen and hydrogen radicals which react with the incandescent carbon to produce carbon monoxide and hydrogen. If there is excess air these themswelves will burn, if not they'll be exhausted.

C + H2O -> CO + H2

CO + H2 +O2 -> H2O +CO2

The same (first) reaction was used to make town gas when it was made from coke. The second reaction was used to cook the Sunday joint.

(I remember both town gas AND Sunday joints, cos I'm old.)

Of course, if engines never need decoking, then you never need to decoke engines, and everything is for the best in the best of all possible worlds.

In the real and sometimes imperfect world, though, it works quite well.

Of course you need to limit the amount of water, to avoid drowning the engine and creating a hydro-lock, which could bend a conrod, but above idle that'd take quite a lot of water. Some people use a hand plant sprayer with an idling engine which is pretty much guaranteed safe, but could take rather a long time.

head gasket - dunno. I THINK its blowing slightly (some coolant loss) but the car is still drivable, though I dunno for how much longer. Clutch is probably on the way out too.

Edited by edlithgow on 29/06/2017 at 16:17

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - John F

Not bull**it - makes perfect sense, as long as the engine carbon is red hot. Thanks for reminding me of the 'O' level chemistry I learned over 50yrs ago! But cautious skidpan, who might be too young to remember either gasworks or 'O' levels, is right in that modern engines don't 'coke' significantly.

So I presume you haven't risked my suggestion of retorquing the head bolts.....

Edited by John F on 29/06/2017 at 19:10

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - galileo

Not bull**it - makes perfect sense, as long as the engine carbon is red hot. Thanks for reminding me of the 'O' level chemistry I learned over 50yrs ago! But cautious skidpan, who might be too young to remember either gasworks or 'O' levels, is right in that modern engines don't 'coke' significantly.

So I presume you haven't risked my suggestion of retorquing the head bolts.....

When I worked in a small iron foundry, at the end of the day the bottom of the cupola furnace was opened and several hundredweight of white-hot coke dropped out: the first few buckets of water thrown on it demonstrated the reaction by generating hydrogen and carbon monoxide and effectively "burning". A few more and the temperature dropped till water started to quench the coke.

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - bazza

I don't think it is worth worrying, as your oil consumption is still low, many VAG owners are using that per 1000 K

My old A series units used a pint or two every 2 or 3 hundred miles, now that was hassle. But tolerances on modern engines are so much tighter, that the days of filling it with gearbox oil are long gone!

There's a great forum called "Bob is the oil guy", which believe it or not talks extensively about this kind of thing.

I might be minded to try a 5-40, out of curiosity, especially if you do a lot of high speed, hot engine work. It might reduce piston blow by, but your oil consumption is so low, I reckon it's all in good order. Overall though, stick with 5-30 and don't move far from it!

Ford Focus Xreg 1.6 Zetec - Thicker oil for old worn engines? - edlithgow

Not bull**it - makes perfect sense, as long as the engine carbon is red hot. Thanks for reminding me of the 'O' level chemistry I learned over 50yrs ago! But cautious skidpan, who might be too young to remember either gasworks or 'O' levels, is right in that modern engines don't 'coke' significantly.

So I presume you haven't risked my suggestion of retorquing the head bolts.....

I've got no experience of modern engines, and don't much want any, but from what I hear ring coking is by no means a purely historical phenomena.

Word on the wire is that BMW's in particular, and German cars in general, can suffer from it, leading to high oil consumption early in life. The neo-mini seems to have developed an especially bad reputation.

Part of the reason may be the skinny wide-range multigrades now in vogue, since the viscosity improver polymers (similar to synthetic rubbers) break down to form tenacious sticky stuff.

Direct injection is a special contemporary coking case, since there is no petrol in the intake air to clean the back of the valves from EGR and blowby residue. This probably wouldn't be effectively cleaned by water either since I doubt it'll get hot enough, though if its really baked on it might be thermally shocked off in lumps Then it'll be a threat to the turbo blades, if you've got them.

Re head torquing just finished end-of-term grading so have had no time, then I have to move house, so it'll be a while before I do anything avoidable to the car.

Edited by edlithgow on 29/06/2017 at 23:26

 

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