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Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - Katie828

Hi, had my i10 SE 64 plate since 2015. Loved the car so far and looked after it. However couple of weeks ago noticed oil light flashing on. Stopped immediately and it was low so topped up. Few days later it went on again so took it straight to nearest garage. They have said its burning oil and needs new engine at cost of £3k minimum. Bit of a shock as no other signs and only has 54k miles clock. Have taken to hyundai and now battling to get repaired under warranty. I got it serviced like clockwork else where and have all the paperwork. However dealership are picking all the invoices apart. Asking for clarification on oil grade even though its specified and questioning parts numbers on invoice. Luckily my garage is great and have written letters confirming what oil they use etc, given all the detailed invoices. I think although you can take car elsewhere for servicing they set the bar so high in terms of evidence you stand no chance of keeping warranty. Its even down to what make of screenwash used? Dealership dont have any empathy at all and just have the strapline 'hyundai wont accept that is in the terms and conditions'. Im not surprised by their reaction as they dont want to pay. Im challenging it as have nothing to lose, just wondering if anyone has any tips on getting them to repair as im left with a pile of metal junk in the meantime and need a car for work so time isnt on my side. Interesting garage said they have seen a similar case of engine failure in a relatively new i10 and again owners couldnt get repair on warranty so im notnholding out much hope.

Edited by Katie Sorrell on 25/07/2019 at 17:14

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - skidpan

You have just discovered why it is pointless having a car serviced outside the official network whilst it is under warranty. Kia have T & C's which are identical to Hyundai's and I can fully accept why they have them. They are giving you a better than average warranty and want to be sure that the customer is keeping their part of the bargain, if I was in their position I would do exactly the same.

I have no idea why people go outside the official dealer network since there is very little, if any, cost saving. When we had our Kia owners on the Forum were saving only about £40 a service but were not getting any campaign updates carried out or the annual body check which can only be stamped by a Kia dealer.. Take the car into a Kia dealership for this work and they will charge you probably 1/2 and hour (normally about £50) and there goes the saving you made on your servicing. And you have also had the inconvenience of 2 garage trips so were is the logic.

Your best bet is to simply get your favoured garage to source an engine from a write off and fit it. If you are lucky and its fine keep the car, if its a bad one sell the car.

And next time use the official network.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - sammy1

you are not alone, put Hyundai I 110 into the search on this site. You do not say when last serviced, but probably a while ago to burn this amount of oil. You say you topped it up but a few days later the oil warning came on again. Question is how can it loose this much oil in a few days without leaking or laying a smoke cloud when driven. If it is not knocking or banging or smoking and you cannot afford an engine try a thicker grade oil and keep an eye on the level.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - skidpan

If it is not knocking or banging or smoking and you cannot afford an engine try a thicker grade oil and keep an eye on the level.

Do not try that.

Engines are designed to run on a certain grade that varies with climate to some degree. Put in a thicker grade and not only will that put extra stresses on ageing components such as the oil pump but it will also take longer to circulate to the top of the engine accelerating wear to components such as cams and followers.

Its a bodge that may have worked in the 60's with old clockwork engines but the OP's engine is a modern unit that is designed for modern thinner but better lubricating oils.

Ask yourself, who knows more The manufacturer, a bloke in the pub or a faceless person on the internet.

Answers on the back of a postage stamp please.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - badbusdriver

I have no idea why people go outside the official dealer network since there is very little, if any, cost saving.

It may simply be down to distance if the dealer is a fair bit away. TBH the i10 does have a very good reputation in general, so the OP probably thought they were safe enough.

Yes, in theory, you can have the car serviced by another garage without invalidating the warranty. But in practice, it will be very very difficult to get Hyundai to honour it. This is why SLO (amongst others) always emphasizes how important it is, if buying a used (but still under warranty) Hyundai or Kia, that it has full dealer service history. This is the only way to be sure that long warranty is still worth the paper its written on.

Fingers crossed that you get the outcome you want, but i'm doubtful. I think the best option is the one skidpan put forward, that being to get your local garage to source a 2nd hand engine. A look on Ebay shows both 1.0 and 1.2 engines for the car available from about £600 (+delivery).

Edited by badbusdriver on 25/07/2019 at 19:12

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - sammy1

As the engine is already *shot* according to the garage what else would you advise. Do you seriously think that a large percentage of car owners are concerned what oil goes in their motor once it reaches an age?

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

If it is not knocking or banging or smoking and you cannot afford an engine try a thicker grade oil and keep an eye on the level.

Do not try that.

Ask yourself, who knows more The manufacturer, a bloke in the pub or a faceless person on the internet.

Answers on the back of a postage stamp please.

Depends on the faceless person on the internet.

If they are saying stuff like ":thinner but better lubricating oil" I'd have reservations, but potentially that's probably the best bet.

The bloke in the pub is probably drunk, and the manufacturer can't be trusted.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

If it is not knocking or banging or smoking and you cannot afford an engine try a thicker grade oil and keep an eye on the level.

Do not try that.

Engines are designed to run on a certain grade that varies with climate to some degree. Put in a thicker grade and not only will that put extra stresses on ageing components such as the oil pump but it will also take longer to circulate to the top of the engine accelerating wear to components such as cams and followers.

Its a bodge that may have worked in the 60's with old clockwork engines but the OP's engine is a modern unit that is designed for modern thinner but better lubricating oils.

Ask yourself, who knows more The manufacturer, a bloke in the pub or a faceless person on the internet.

Answers on the back of a postage stamp please.

OP, just in case you take the above seriously, be aware that its a lubrication legend and has essentially no visible means of support.

In general, thin oils are specified for fuel economy, and the overall balance of the evidence is that thin oils cause slightly higher wear.

This is a compromise, and for most owners, most of the time, and entirely reasonable one, since most cars are scrapped with lots of engine life left.

However, compromise doesn't make good advertising copy so you won't find it explicitly acknowledged by manufacturers.

We don't know if thicker oil will help you, but if you use it the dire consequences foretold above are rather unlikely

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - RT

If it is not knocking or banging or smoking and you cannot afford an engine try a thicker grade oil and keep an eye on the level.

Do not try that.

Engines are designed to run on a certain grade that varies with climate to some degree. Put in a thicker grade and not only will that put extra stresses on ageing components such as the oil pump but it will also take longer to circulate to the top of the engine accelerating wear to components such as cams and followers.

Its a bodge that may have worked in the 60's with old clockwork engines but the OP's engine is a modern unit that is designed for modern thinner but better lubricating oils.

Ask yourself, who knows more The manufacturer, a bloke in the pub or a faceless person on the internet.

Answers on the back of a postage stamp please.

OP, just in case you take the above seriously, be aware that its a lubrication legend and has essentially no visible means of support.

In general, thin oils are specified for fuel economy, and the overall balance of the evidence is that thin oils cause slightly higher wear.

This is a compromise, and for most owners, most of the time, and entirely reasonable one, since most cars are scrapped with lots of engine life left.

However, compromise doesn't make good advertising copy so you won't find it explicitly acknowledged by manufacturers.

We don't know if thicker oil will help you, but if you use it the dire consequences foretold above are rather unlikely

As manufacturing tolerances have shrunk over the decades, the recommended oil has reduced from 50 > 40 > 30 and at the same time the cold W rating has reduced to 0W - this means that oils SEEM very thin because they're poured when cold but the reality is that s straight 40, 15W-40, 10W-40, 5W-40 and 0W-40 are all the same viscosity when hot (ie most of the time) despite very variable viscosity when cold - in fact the THINNER the oil when cold, the better as it gets up to prsssure quicker to protect the engine when cold, which is when most wear occurs.

The internal temperature of an engine varies little between hot and cold climates so there should be no variation globally in the recommended hot viscosity for a specific engine.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

The internal temperature of an engine varies little between hot and cold climates so there should be no variation globally in the recommended hot viscosity for a specific engine.

I'm told hot engine oil viscosities are, or were, systematically higher outside the US than in, and in particular, consistently higher in Australia.

This is generally and plausibly believed to be because of the CAFE fleet fuel economy targets that US manufacturers have had to meet for a long time.

As similar regulations become applied in other markets, that difference will probably erode.

Edited by edlithgow on 27/07/2019 at 11:50

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

As manufacturing tolerances have shrunk over the decades, the recommended oil has reduced from 50 > 40 > 30 and at the same time the cold W rating has reduced to 0W

I think you are confusing "tolerance" and "clearance"

"Tolerance" is the allowed variation from design specification. This has got systematically smaller, due to better quality control and manufacturing technique. This has no obvious implications for oil viscosity.

"Clearance"" is the design separation of parts.This could have implications for oil viscosity, but I don't think, in general, it does.

I'm not sure clearance has got systematically smaller, and even if it had that wouldn't necessarily mean that this was the reason for the move to skinnier oil..

This thread

https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3947115/1

contains a specific comparison of clearances in a 1985 and 2012 Honda. No systematic difference.

Only 2 cars though. There may be a larger scale comparison out there but I don't have time to look for it right now.

Ellsewhere in that thread its stated that some clearances have opened up to reduce frictional losses which impact fuel economy.

Fuel economy is mostly what this is about..

Edited by edlithgow on 27/07/2019 at 12:38

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - Katie828

Actually it last had a full service end of january. Was coming up to interim service.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - Katie828

Yes appreciate point but i went elsewhere after official garage tried ro charge me £100 per tyre and just didnt like the people there. Transpired it was a typo but the argument i had to have to get them to check given they work with cars every day. Anyway im just going to appeal and go to ombudsman etc in terms of warranty. Its clear they are going to say no before i even produce the next piece of paperwork they ask for. Bit miffed they havent actually gone to hyundai to ask them so i have nothing formal in writing to say they are refusing yet. Have nothing to lose do i in terms of challenging it? Rather buy a cheap 3k car than buy a new engine.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - gordonbennet

I'm afraid this engine sounds like another victim of no one regularly checking the oil level, to get down so low the oil light was coming on means its been running low on oil level for some time, and all this does is accelerate engine wear, getting it serviced once the low oil accelerated wear has taken place is no use, the damage cannot be undone, it will continue to use oil rapidly meaning topping up continually.

Checking the engine oil level on a flat surface should be done at least once a fortnight, at least once a week if you cover a fair mileage, and coolant levels should be checked once the engine has cooled down too, i've seen dozens of modern cars sat on the hard shoulder of motorways this week, the M11 northbound yesterday was fair littered with modern euroboxes, and yes premium German badges featured in number.

Edited by gordonbennet on 25/07/2019 at 19:35

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - John F

I'm afraid this engine sounds like another victim of no one regularly checking the oil level, to get down so low the oil light was coming on means its been running low on oil level for some time,

Agreed. But some questions for the OP - is it driveable? If so, how much oil per 1000 miles is it using? The garage which advised a new engine might be looking for work. If the engine runs OK and burns less than a litre of oil every 1000 miles she might as well continue to use it - and it might even pass the MoT emissions test. Engines have seized after the service mechanic failed to replace the oil - or were run experimentally with no oil in a scrap car by the curious - and were still serviceable when refilled.

Checking the engine oil level on a flat surface should be done at least once a fortnight, at least once a week if you cover a fair mileage, and coolant levels should be checked..

Distance, not time. Even with over 100,000 on the clock you should not need to check the oil more frequently than every 1000 miles unless it's a known oil burner. E.g. our 140,000 mile 1.6 Focus does over 3000 miles per litre.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - RT
Distance, not time. Even with over 100,000 on the clock you should not need to check the oil more frequently than every 1000 miles unless it's a known oil burner. E.g. our 140,000 mile 1.6 Focus does over 3000 miles per litre.

How do you know whether it's an oil-burner without regular checks?

Routine is good discipline - nothing wrong with a 3-minute weekly check of a car's fluids before starting it for the first time that day - all visual except the engine oil - automatics though need to be checked when warmed up.

My 98,000 Astra 1.8 used about a 1/4 of a litre in 6,000 miles - running better than when new - used Mobil 0W-40 with two interim oil changes between each 20,000 mile service.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - sammy1

Rather buy a cheap 3k car than buy a new engine.

Agree with this statement, if the worse happens better off getting what you can for the Hyundai and start again. By the time you source a new engine and pay the labour to change it, not worth the risk that the engine you buy could be a dud!

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - Andrew-T

I have no idea why people go outside the official dealer network since there is very little, if any, cost saving.

You are being a bit disingenuous here, Skidpan. One obvious reason that comes to mind is that the OP has no nearby dealer but is on the books of a good trusted local independent. The direct 'cost saving' may be only moderate, but the extra convenience may be worth a lot.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - NARU

...Asking for clarification on oil grade even though its specified and questioning parts numbers on invoice....

I've heard this before with Hyiundai. To the extent of them even sending away a sample of the oil in the engine for testing.

Fair play to them, when the test came back showing the correct oil they paid for the new engine (Santa Fe, so not cheap).

And when it concerns a car burning oil, I can fully understand why they do it.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - RT

The 2010 facelift Santa Fe received an all-new 2.2 diesel and needed ACEA-C3 oil as it had a DPF - but several Hyundai dealers carried on doing oil changes with an old specification and needed to be forcibly called out by an owners group and get pressure from Hyunduai UK to inform its dealers better.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - nortones2

As they won't say, wrong oil - cheap insurance. For dealers. Hoping the owner won't twig.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - skidpan

You are being a bit disingenuous here, Skidpan.

Why, that has been my experience of Kia (Hyundai's sister brand) and other brands as well. When the Micra was over 3 years old the main dealer charged far less to service it than any local indie would and they did cheap MOT's as well. Since the OP has not said anything about their location or distance to the nearest main dealer we do not know if convenience is the reason. But I will repeat what I said before, you need to go to an official dealer to have campaign updates and the rust stamp in the service book. No rust inspection, no 12 year warranty and since some campaign updates are to prolong component life if they are not carried out it is another reason to refuse warranty cover should a failure occur later.

As they won't say, wrong oil - cheap insurance. For dealers. Hoping the owner won't twig.

Do not understand the above, explanation please.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - bazza

Sorry to hear of this situation, very common dilemma. Best bet as skidpan suggests, source a used motor from a breaker, do your homework and check warranty etc before buying. Going rate on eBay looks like 600 to 900 pounds or so. A few hundred to fit at an indie. Drive it for a few weeks and monitor carefully. Keep if ok. Sell if any doubts. Best of luck

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - alan1302

Why, that has been my experience of Kia (Hyundai's sister brand) and other brands as well.

The two Hyundai dealers nearest me were both a lot more expensive than any of the independent garages and much less convenient to get to as well. I did claim on the Hyundai warranty for a power steering failure without an issue.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - FiestaOwner

Why, that has been my experience of Kia (Hyundai's sister brand) and other brands as well.

The two Hyundai dealers nearest me were both a lot more expensive than any of the independent garages and much less convenient to get to as well. I did claim on the Hyundai warranty for a power steering failure without an issue.

The other reason people use independent garages is that they don't trust the main dealers.

Where I stay, the huge dealerships have taken over virtually all the franchises (Arnold Clark, Evans Halshaw etc). I think you get better service from the smaller family owned dealerships. The only dealership locally that isn't owned by own of the big chains is the Ford one.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - catsdad

My trust in all dealerships and indies is limited .My once trusted indie tried to stuff me for 4 new tyres when the "worn" ones were actually 2-4 times the tread limit. My next one charged me considerably more for Corsa front pads than the VX menu price. Now on my third indie and so far so good.

But even he can't compete on the Honda menu service price with free MoT and breakdown. I doubt too that he can possibly stock the wide range of oils to service multiple makes to full spec. On the other hand he did a great job refixing a fog light that bust its mountings when it lost an argument with a pheasant. The Honda dealer would have charged significantly more than the £40 I paid.

Around here then it seems you can't generalise.

Good luck to the OP with the issue. All manufacturers hide behind "normal" rates of oil consumption that most owners would regard as excessive. The oil warning however is not necessarily damning. I got an oil warning message on the Civic, despite regular checks, but it was still marginally above minimum on the dipstick. So Hyundai may build in a similar margin?

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - skidpan

As manufacturing tolerances have shrunk over the decades, the recommended oil has reduced from 50 > 40 > 30 and at the same time the cold W rating has reduced to 0W

I think you are confusing "tolerance" and "clearance"

Tolerances and clearances are linked.

As the manufacturing tolerances have reduced it has reduced the clearances on the engines that are built to the maximum tolerances.

A blueprinted engine built today using "perfect" components is probably no better than one built 60 years ago except of course materials have improved.

But lets not forget that oils have improved massively since the early 80's. You needed thicker oils back then because a thin one would never have held together at higher temps. Now with synthetic oils a thinner one will hold together and will lubricate far better than its much thicker ancestor. The advantages of the thinner oil have resulted in less pumping loss which means more power/better economy.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

For a skinny oil requirement to be forced by a change in clearances to make sense, they would have had to have got narrower. I havn't seen any evidence that they have.

I'm not surer what you mean by "hold together" so I can't really comment on that.

If you mean resist chemical / physicall breakdown and so maintain viscosity for longer, synthetic oil does generally do that, but that isn't due to its low viscosity..

My SAE40 isn't going to sheer to SAE20 within my OCI

Saying thinner oil will lubricate far better than thicker oil is, however, pretty much a contradiction in terms, since hyydrodynamic lubrication is a function of viscosity. Additives make a big difference only in boundary lubrication. .

Re "The advantages of the thinner oil have resulted in less pumping loss which means more power/better economy." er, yeh.

Skinny oil is specified for superior fuel economy, not superior wear protection

Edited by edlithgow on 27/07/2019 at 15:53

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - skidpan

I'm not surer what you mean by "hold together" so I can't really comment on that.

If you mean resist chemical / physicall breakdown and so maintain viscosity for longer, synthetic oil does generally do that,

That is exactly what I meant.

but that isn't due to its low viscosity..

Correct and I never said it was. Quality has nothing to do with viscocity

Saying thinner oil will lubricate far better than thicker oil is, however, pretty much a contradiction in terms, since hyydrodynamic lubrication is a function of viscosity. Additives make a big difference only in boundary lubrication.

Example. When Ford introduced the Zetec to the world back in the early 90's early examples had problems with sticking lifters. Fords "bodge" was to change the oil spec from 10w40 to 5w30, both semi synthetic. No more problems simply because the thinner oil was able to get where it was needed especially on cold start ups. The thinner oil was able to lubricate better but due to advances in oil tech still stayed in grade. Not sure what Ford specify for the EcoBoost engines but all the N/A engines and Turbo Diesels until about 2015 used 5w30 in the UK, may be different in other climates.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

I'm not surer what you mean by "hold together" so I can't really comment on that.

If you mean resist chemical / physicall breakdown and so maintain viscosity for longer, synthetic oil does generally do that,

That is exactly what I meant.

Actually thats an oversimplification and I was wrong to concede that. I was late for an appointment.

I don't believe synthetic oils are necessarily more sheer stable than mineral oils. The base oil in both cases is very sheer stable,

What sheers is the viscosity improver, and in, say an old-fashioned 20W50 multigrade it might sheer quite a lot on an over-long OCI.

It will not, however, sheer below the viscosity of the base oil.

Your inference that thicker oils were specced so they'd retain some viscosity at the end of the oci doesn't ttherfore seem to make much sense.

They were specced because they wanted thicker oils.

As far as I can tell it makes even less sense if you are talking about chemical (primarily oxidative) as opposed to physical breakdown. Theres no obvious reason to suppose thicker oil is more stable chemically than thin, and oxidation doesn't involve simple viscosity loss.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - RT

Any given engine will have an optimum viscosity at operating temperature - even with modern multigrade, the viscosity at start-up temperature will still be higher than optimum - but the lower that cold viscosity, the nearer to optimum it'll be.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - sammy1

*boundary lubrication* That's a new one to me!

Has any car engine been proven to have failed because it's oil has * broken down"

I had a boss who had a Hillman Avenger 1600 petrol. He commuted from Scotland to Wales and back on a weekly basis and his car was used as the depot run around while on site. the oil was hardly ever changed on the car and when I drove it was the most flexible *loose" engine and eager motor I have ever driven. The car was driven over 1000miles per week and I remember the exhaust pipe was always a white residue, a sure sigh of efficient combustion.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

*boundary lubrication* That's a new one to me!

Its where you;ve got "hard"" contact between surfaces. Some anti-wear additives form a layer bonded to the surfaces to limit damage.

More likely to happen with thin oil. Additives are used to compensate for its poorer hydrodynamic lubrication.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - SteveLee

The best metal to metal protection - bar none – zinc, has been largely removed from oil as it contaminates catalytic converters. Oil hasn't got thinner because engine tolerances are better, it's to enable manufacturers to fit cheaper starter motors and batteries as well as con the fuel-economy and emissions tests. Thicker oil lubricates certain bearing surfaces better (particularly cam lobes) simply because it’s less likely to be flicked off the lobe and break the hydrodynamic wedge. Similarly, thicker oil is less likely to be thrown from crank journals – although cross-drilling of oil feeds is pretty much universal these days lessoning this issue. If water had a higher boiling point then it would work reasonably well a “lubricant” for a running engine, as once an engine is running almost any oil will do the job (unless ultra high temps are involved such as cooling turbochargers). Most wear it at start-up before the hydrodynamic wedge is built up which is actually what keeps metal from metal - not the lubricity of the oil (particularly in the absence of zinc). We are used to engines out-living cars these days – I suspect those days are over now start/stop is common and we fill the sump with ridiculously thin oil.

The other thing to mention with modern oil is it an increasingly significant percentage of your “oil” is actually not lubricative – these additive packs are designed to do jobs such as keep the engine oil chemically stable over (ruinously) extended service intervals, so the oil does not become too acidic and attack bearings or seals, they also have additives designed to suspend small wear particles in the oil (turning your oil into a fine grinding paste) rather than letting them sink to form sludge. This is because oil filters are more porous than ever – or they’d block too quickly to last 20K miles. The bottom line is change your oil and filter between services if you want your engine to last longer. The manufacturers couldn’t care less about engine longevity as long as they make it past the warranty period.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - Andrew-T

Interesting, Steve, and it makes a lot of sense to me. Also a good example of how 'optimising' any system can amount to choosing the best compromise among all the trade-offs.

Hyundai i10 SE 2015 - Burning oil problems claiming on warranty - edlithgow

For a skinny oil requirement to be forced by a change in clearances to make sense, they would have had to have got narrower. I havn't seen any evidence that they have.

Little bit more circumstantial evidence readily to hand

PDF Charade engine manual, covering CB-23, 61 and 80 engines.

(Mine is a CB-22, very similar to CB-23)

That's to some extent a developmental series, with the bigger numbers being more powerful and sophisticated, though I dunno offhand what the respective inception dates were, and they were in parallel production.

The bearing clearance specifications are given as a range, with a separate maximum allowable limit.

All the same, except for the CB-80, which has a slightly bigger minimum with some.

By no means conclusive, but perhaps an iindication that the simple story skirts the truth .