Oil consumption increases when car driven fast.

I have 2.2L 1996 Camry with 153000m. The car goes well though some power loss is noticeable. I noticed that engine oil level reduces if car is driven at speeds higher than 75mph (for short distances) and I have to add more oil. Is this normal?

Reply to
Jager
Loading thread data ...

You CAN be specific, like a 1/4 quart in 3000 or 2 quarts in 1000m, But I guess we should read your mind , right ... Did you do a compression test , of course not, you are an )(*&%..

Reply to
m Ransley

Thats normal with that many miles - oil gets hot and oil vapors get sucked past rings and valves to be burned. Have you ever replaced the PVC valve. If the $10 PVC valve doesn't help - the alternative is use thicker oil or rebuild the entire engine.

Reply to
Wolfgang

If the consumption is a quart per 1000-1500 miles that's perfectly normal. If you start using a quart in less than 1000 miles then something nastier than ordinary wear might be knocking. In any case, oil is cheap, a rebuild ain't. Add more and live with it. No big deal.

Reply to
pheasant

formatting link

Reply to
Daniel M. Dreifus

Author killfiled for wasting bandwidth with rude and uncalled for comments. Plonk!

"When a legislature undertakes to proscribe the exercise of a citizen's constitutional rights it acts lawlessly and the citizen can take matters into his own hands and proceed on the basis that such a law is no law at all."

- Justice William O. Douglas

Reply to
MisterSkippy

As engines become worn, there is increased chances for oil consumption to rise.

- both compression and oil-control piston- rings act as scrapers to remove oil which has collected on the cylinder walls,..but not removing it all as some has to remain to act as lubrication or to stop direct ring to cyl-wall contact. As the rings wear and lose their expand-tension, this scraping effect becomes less effective leaving more oil to be burnt on the power-stroke.

In parallel with ring-wear the ring grooves in the pistons become wider and along with ring wear which meansthe space behind the rings gets larger in the piston-grooves, oil-pumping starts to occur. Basically, oil is always sitting behind the rings in these grooves which aids ring sealing (which stops compression loss), but once these critical dimensions increase, oil is more easily sucked up into the combustion chamber on the intake stroke. This pumping action comes from the rings scraping oil off the cyl-wall, some of which collects behind the rings and inbetween the rings,..then on the intake stroke this oil is sucked up into the comb'chamber.

- increased blow-by ( hot combustion gases on the power and exhaust stroke getting into the sump under pressure))which is caused by worn rings failing to provide a good seal with the cyl wall. This increase in sump or crankcase pressure causes the oil-mist whose presnce is normal, to be pushed out into the PCV system and burnt via the intake.

- during the intake stroke oil can also be sucked into the combustion chamber via increased clearances in the valve guides and by worn valve seals

- bearing wear can also cause more oil than normal to be sprayed up onto the cylinder walls as the oil, under pressure escapes from the crankshaft rod-bearings.

- increased clearance between the piston itself and the cylinder-wall also contributes to loss of oil control, tho to a lessor extent.

As long as sufficient oil-changes are done on an oil-consuming engine as more oil pollution occurs due blow-by, then some degree of protection occurs, but inevitabley all this increased oil-burning leaves behind carbon which collects in the worn ring-grooves causing eventual ring-sticking and breakage. In this event the cylinder fails to produce enough compression for effective combustion, and the engine loses a lot of power. Also, the combustion chambers get clogged with more carbon. This causes pre-ignition as the carbon glows thus igniting the fresh charge either before the spark or in combination with the spark causing detonation (detonation is an uneven flame-front during ignition of the fuel-air charge).

One final event which often spells the end for an oil-burning engine is piston failure. The cause is directly due to the rings becoming stuck or broken,..but still sealing enough to allow some combustion (power-stroke). Because the rings are allowing a large amount of blow-by, the piston on long or high-speed trips, becomes overheated by the ultra-hot gases flowing past it. Once this reaches a critical point, the aluminium literally starts the first stages of melting and undergoes what reconditioners call a "piston collapse". The piston still looks like a piston,..but once measured with a micrometer, it is found to be significantly undersize. In this state the piston becomes quite noisy with a lot of smoke being generated from the PCV system.

Personally,..once an engine starts burning more than a quart (litre) per 300 miles or so,..I'd restrict speed to no more than 60 mph.

Jason

Reply to
Jason James

Your suggestion is valid, but last bit of your response was rude and out of character for you.

Reply to
Car Guy

I agree with Car Guy, this sort of abuse isn't really needed, and as a newbie I was disappointed to see it in this group.

Geoff

--
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
 Click to see the full signature
Reply to
Geoff

Kudos to Jason!!

That was a very concise explanation of oil consumption. More than most (me included) care to take the time to write, and yet when I see someone take the time to do such a thorough job, it makes me feel good that Usenet still functions as intended in most newsgroups. (and a bit guilty that I didn't take the time and make the effort myself) Hats off to this fine post. Wish I'd done it. :)

Thanks Jason!!!!!

Mark

Reply to
pheasant

Jason, Everything you've described sounds accurate. The original poster had power loss and increased oil burning at around

150,000 miles. Thing is, with Toyota Camrys, receiving regular service, many, many engines are reported operating well to 200,000 and 300,000 miles and more. Someone who's been seeing 400,000 miles and more from Toyotas reported the following typical usage patterns (his numbers, not mine): 0 - 50,000 miles: 1/4 to 1/2 quart per 3000 miles. 50.000 - 100.000 miles: 1/3 - 3/4 quart per 3000 miles. 100,000 - 200,000 miles: 1/2 to 1 quart per 3000 miles. 200,000 - 400,000 miles: 3/4 quart to 1 1/2 quart per 3,000 miles 400,000 - 600,000 miles: 1 - 2 quarts per 3,000 miles. (end quote) Now if the original poster's engine oil and or filter changes have been extended it is possible the wear scenarios you outlined are in effect. But if the physical, mechanical wear is typical, could just be sticking rings, the reason I gave the earlier link for auto-rx.com which is supposed to remove carbon from the rings, safely without rebuilding the engine. Toyotas are built with so much more exacting tolerances and assembly methods than engines with which I've been familiar in the past, that at 150,000 miles, the engines are usually in great condition with none of the advanced wear characteristics you have so aptly described. Used to be, if your engine saw 100,000 miles, you were doing well, but I'm still driving a 1977 Toyota 4 cylinder pick up truck that's flipped over the 100,000 mile odometer so many times I've stopped counting, still has plenty of power, and uses 1 quart of oil (Valvoline 20W50) in 3,000 miles. Perhaps the original poster could check the valve clearances as a proxy for engine wear. I'm always amazed at how well those clearances remain in tolerance as the miles accumulate. Those four cylinder engines with the cast iron block are often described as "bulletproof" or "run forever" - and with proper care, they usually do. Now if something's been amiss - over heating, leaks in the air intake tubing, or a variety of other factors that could alter normal operation over time, that could explain the problem. But to answer the original poster's original question, "Is it normal for high speed driving to increase oil consumption" - Toyota's answer is that some oil consumption is normal - but should remain reasonable unless something else is wrong. I've got the same engine in a Camry with 125,000 miles, and oil consumption stays about the same whether driving primarily around town or up on the highway at high speed. Now, I notice the original poster's country code is Germany - if he's driving well over 75 mph, like 90 mph and higher, more oil usage could be perfectly normal. Ransley's uncivil queston then becomes relevant again: How much oil is being used, and at what speeds?
Reply to
Daniel M. Dreifus

I agree with what you have described also Daniel,..but you may have noticed I didn't mention at how many miles these progressive wear characteristics occur. There is a good reason for this ie,.. There are significant variables at play with each person's car-engine,..not the least of which is maintenance and the occurance of mishaps such as over-heating, or worse, lack of oil-pressure..even for a short period during the engine's life. Then you have what is called 'driving style' which is a euphemism for how a driver treats their engine interms of lugging (only applies to manual-trans) or over-revving etc,,,.. Like I said, there are too many variables to put absolute miles on it.

I used to maintain my FIL's taxi (what a nightmare,..he got it with 350,000 miles on it's engine). It chucked a rod at 550,000 miles which was early for a taxi which was well maintained. The bad part of that particular exercise was I *knew* it was going to throw a rod soon,..as I could hear the rod-bearings on feathered throttle,..but he insisted "it was OK"....... So why did it suffer bearing failure? I have know idea, for I didnt have the knowledge of what had happened to the engine in it's earlier life.

My post on oil-usage is simply what I have experienced with about half a dozen engines that I pulled down after some of which had failed completely, others which had started using more oil than normal,...

I think, suffice to say,..its not unusual for engines to use more oil at high speed. Why? Perhaps the oil gets a bit thinner and therefore more able to be sucked up into the comb-chamber,..or crankcase pressure rises pushing more into the PCV?

There are cases which actually surprise. I know of an '86 Nissan Pulsar (fitted with that GM J-car engine) which reduces oil-usage on trips. That engine has had a 'rering' after a bad overheat. The mechanic just honed the bore and re-fitted the original pistons with new rings. Around town, it puffs blue smoke on gear-changes and uses significant oil *yet* on a trip it used less oil! So why? The only thing I can think of is that at increased revs the combustion gases push the rings against the bore, which in this engine's case, reduces oil-consumption.

Absolutely,....all things need to be chucked into the mix,...whether we can get a meaningful answer???

Jason

Reply to
Jason James

to

(me

still

Thks Mark,...but it was just things I have noted over my earlier years with the old cars I used to have (folding-stuff was in short supply!). I used to dismantle them to find out why they had failed or were using a lot of oil,.. plus some friend's car-engines.

Hasten to add tho,..my '96 Camry which I bought with 95,000 miles on it,..has some sludge due poor maintenance. I kicked myself for not checking the engine more thoroughly,...anyway, even tho it has some signs of neglect it still has excellent oil-control,..tho I dont thrash it or drive at more than posted speeds which out here is usually no-more than 60 mph.

Jason

Reply to
Jason James

For an explanation of oil consumption see:

formatting link

formatting link

formatting link

Also see:

formatting link

formatting link

Or just do a Google Groups search.

Ed

Reply to
C. E. White

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.