Viewing 26 posts - 41 through 66 (of 66 total)
  • Scary oil change
  • Sui
    Free Member

    As long as your oil has the right industry specs there’s no reason to go for a fancy brand.

    that’s not true, and that “bible” was written by people with an agenda. Yes you meet a standard, but it doesn’t mean its any good!

    Inbred456
    Free Member

    Moly are there sensors to actually monitor oil quality or does the engine management just work out how many short runs, stop start, motorway miles the car has done and adjust service intervals to suit. Think its the latter. Would need some pretty good tech for the engine to check its own oil quality. I’m on fixed every 10k on the Skoda but have never had any luck on the variable, it’s always come on at about 10050. I’m a bit OCD about oil changes. Change it every 5 to 6k and the filter every 10 to 12k.

    aracer
    Free Member

    +1 to all of that.

    Fresh Goods Friday 696: The Middling Edition

    Fresh Goods Friday 696: The Middlin...
    Latest Singletrack Videos
    hot_fiat
    Full Member

    Castrol edge is £32.38 at Costco.

    onewheelgood
    Full Member

    My A6 2.7TDi has done 196000 miles. The oil has been changed 9 times. Still seems to go OK.

    ross980
    Free Member

    squirrelking
    Free Member

    If there aren’t sensors in a multi million ship engine then I guarantee you there won’t be in your tiddly little block regardless of how fancy you think it is. The most you’ll be looking at is a differential pressure sensor across the filter which could be knocked out by a hole in the filter, thinner filter or a multitude of other variables.

    People seem to be forgetting that oil degrades through time as well, it’s hygroscopic so the longer you leave it the more it breaks down. I’d certainly never consider leaving untested oil in an engine for any length of time longer than a sensible service interval. I’m sure you can get the testers for home use but would imagine they would be difficult to find.

    And people wonder why their turbos keep failing…

    Oh, why would the DPF dump to the sump? That makes no sense at all as it has nothing to do with the oil system!

    molgrips
    Free Member

    If there aren’t sensors in a multi million ship engine then I guarantee you there won’t be in your tiddly little block regardless of how fancy you think it is.

    Whoah that’s hostile!

    squirrelking
    Free Member

    Sorry, wasn’t intended to be. I myself own a tiddly little block 😉

    My point was that if a cutting edge 250k HP monster doesn’t have that sort of capability (and believe me, if they thought they could fit it they would) then a car engine sure as anything won’t.

    molgrips
    Free Member

    Well now I have no idea what engines have it and don’t have it 🙂 I was just conjecturing based on what VCDS said (ie it told me about soot content) and what someone else said on a forum. However hence my question – it would seem to be rather hard to actually monitor oil quality on the fly.

    konabunny
    Free Member

    Well now I have no idea what engines have it and don’t have

    Apparently they’ve got a bit more poke than you were expecting too…

    Sui
    Free Member

    bloody hell squirrel

    Oh, why would the DPF dump to the sump? That makes no sense at all as it has nothing to do with the oil system!

    because that’s where it goes, even the TheAA man knows that..

    http://www.theaa.com/motoring_advice/fuels-and-environment/diesel-particulate-filters.html

    What you need to remember is that LD (light duty) Automotive engines are WAY WAY WAY ahead in technological advancement that HD (HEAVY DUTY) Diesel engines, they’ve only just got round to EU V and VI, and SHIP engines – well they will be lucky to see the equivalent ever!

    squirrelking
    Free Member

    Huh, didn’t know that, what a bloody stupid idea. Don’t own a DPF so never really read up on the newer types.

    As for car engines being more advanced, sorry, I must correct you as you clearly know nothing about the marine world. Marpol Annexe VI has been in force for years now, SOX and NOX emission reductions are a constant source of innovation and technical challenges. They’ve been unsing water injection in place of EGR’s for years, camshaftless engines are old hat (they just make control too difficult) and maintenance and testing is far more rigorous than anything on the roads.

    FFS, car engine makers go on about common rail as if it’s a new thing, ships were using it way before cars!

    hot_fiat
    Full Member

    That’s a bit harsh. Without ship engines we wouldn’t have Piezo-electric fuel injection in automotive diesel engines. Ship fuel efficiency and potential exhaust cleanliness are far ahead of those in any wheeled vehicle. Simply because they haven’t had to comply with any emissions regs doesn’t mean the technology’s not there. Wait until next year: it’s all about to change.

    Sui
    Free Member

    I’ll admit my exposure to Marine sector is limited, but I have some experience and I still think it’s way of. That said, 2 entirely different applications which merit their own progression in terms of advancements. Oil specifications for ships engines are a different beast and continually monitored for metals, viscosity, soot, Ash, and glass and silicon particles (the glass comes from sand being super heated as it’s drawn through the breathers).

    squirrelking
    Free Member

    Just did some reading, the diesel doesn’t dump at all (hence why you should always take AA web writers advice with a pinch of salt). What actually happens is that unburnt fuel can make its way past the piston rings (probably worse on unmaintained engines ;)) and sits in the sump. Before FAME’s were allowed (biodiesel fatty acids)it would evaporate away but now the biodiesel content is there by law you can’t do much about it just sitting there.

    Actual facts: http://www.stocksy.co.uk/articles/Cars/diesel_particulate_filters_dpfs_and_rising_oil_levels_the_uk_government_demonstrates_the_law_of_unintended_consequences/

    squirrelking
    Free Member

    What sand? What breathers?

    Do you mean the turbochargers or something else? Because if a breather is letting air IN there’s a seriously dangerous problem at hand!

    FWIW I was, until recently, a fully qualified 3rd engineer so I do know what I’m talking about. The sector is not “way of[sic]”. At least not in the direction you seem to think anyway…

    HoratioHufnagel
    Free Member

    Its certainly possible cars are monitoring oil contamination directly. e.g. GM oil sensor (from 1980)
    https://www.google.com/patents/US4345202

    Sui
    Free Member

    breathers / air intake Piston side. Sand gets sucked in when in port (same as Gen sets), gets super heated and dragged in through the seals to the sumps.

    Squirrel I’m not doubting your experience or what you do, so please don’t get wrong end of the stick. I come from a purely lab and theory background working with the producers. I did almost go to work for Valvoline and one of my jobs would have been monitoring oil condition at power stations and ship supplies in order to determine oil service intervals.

    Sui
    Free Member

    Horatio

    Bosch have a number of sensors for Sump -conductivity is one, which monitors metals in the oil, and also viscosity doen through sonic monitoring. Those combined with drive cycle analysis, DPF regen failures all = variable service intervals.

    molgrips
    Free Member

    What actually happens is that unburnt fuel can make its way past the piston rings (probably worse on unmaintained engines ;)) and sits in the sump

    I knew that 🙂

    Usually, regeneration involves injecting diesel during the exhaust stroke,

    Some engines (PSA I think?) use an extra injector in the exhaust manifold, I think.

    Huh, didn’t know that, what a bloody stupid idea.

    What’s your solution then?

    aracer
    Free Member

    If marine engines are so advanced, why are the ones I come across when kayaking on the river so stinky?

    Sui
    Free Member

    Some engines (PSA I think?) use an extra injector in the exhaust manifold, I think.

    i think Nissan do as well.

    emission’s are hard to control, you need a mix of DPF, EGR, inline additive and sometime SCR to get the job done.

    molgrips
    Free Member

    .. on diesels… petrols don’t need many or any of those things.

    I’d still like to see a proper assessment of the impact of battery manufacture in hybrids against the issues of diesel.

    squirrelking
    Free Member

    Ah right, lab side, that explains things 🙂

    aracer – same reason strimmer engines are shit I suppose?

    molgrips – no solution other than injecting after the exhaust mani, stops diesel leaking into the sump. Even better solution is water injection – cool the combustion with water molecules and the NOX won’t form, this removes the need for an EGR and by association the DPF (particulate generation is higher due to unburnt fuel thanks to oxygen starvation in the combustion process). Requires nothing more than another water tank in the front (but you can’t make money off it like you can with adblue refills).

    squirrelking
    Free Member

    Well, the DPF can be lost to a larger extent. Petrol has EGR as well although it would seem that it’s of some benefit in that case rather than a soot/sludge generator.

Viewing 26 posts - 41 through 66 (of 66 total)

The topic ‘Scary oil change’ is closed to new replies.