What causes Oil Consumption

Status
Not open for further replies.
Originally Posted By: LeakySeals
From new it will/might prevent. Try it with a used car and see what happens. I'm 0 for 6. Fools gold to think syn will magically make oil burning go away. Once a burner, stay with dino, a High Mileage oil, or get it repaired.


This is the way I would feel about many cars/engines. But each case is different. I have had luck with flushes and High Mileage oils, in our service vans at very high mileages we routinely go up a grade as oil consumption increases. In the last 3 engines we have rebuilt I have personally been there when they were torn down and the oil rings were coked up and sticky in their grooves.

Easier to KEEP them clean from the start.

But there will always be a few cars that simply use too much oil no matter what you do.
 
Last edited:
Originally Posted By: Realtech214
Other than engine wear what causes an oil to "burn" in an engine. As i have said before, Pennzoil conventional stopped oil consumption from 1 quart ever 2500-3000 miles with gtx to 0% with Pennzoil conventional. Just want to know What properties of oil are good at preventing oil loss?

- I'll never use Castrol again , also where can i get Pennzoil transmission fluid... Other than the internet?

Changing oil brands (keeping the viscosity same) does not cause a big difference in oil consumption. There should hardly be a difference going from GTX to Pennzoil conventional vice versa.

Your experiment is almost certainly in error. Chances are that you overfilled with Pennzoil conventional, underfilled with GTX, or both. There could also be factors as oil temperature during oil-level check, fuel dilution, etc. In most likelihood you don't have a long-enough OCI with Pennzoil conventional yet for good data on consumption, as you say it's only been 1000 miles so far. You can't judge much in 1000 miles. In addition, dipstick readings can correlate with the actual oil level in a very nonlinear way when the oil level is near the full mark. (By the way, I am assuming that you didn't perform any engine repairs.)

Almost certainly faulty experiment, faulty conclusion.
smile.gif


Oil consumption, excluding oil leak, is caused by worn valve-stem oil seals or worn rings/cylinders, and there is no cure other than engine repair for that. You can't cure it by using a different type or brand of oil. However, going to a thicker viscosity can decrease the consumption up to two or more times, depending on how thicker yo go. Lower NOACK volatility also helps but not as much. Besides Pennzoil Conventional and Castrol GTX should have about the same NOACK volatility.

Let's see your consumption data after 4,000 more miles when you reach 5,000 miles. I bet you will have to add at least a quart bottle of Pennzoil conventional makeup oil to keep going.
smile.gif
 
Originally Posted By: BlueOvalFitter
Originally Posted By: jfking106
Gremlins.


Which one?

pgoq.jpg

3c8e.jpg




The top one.
wink.gif


My dad bought a green Gremlin back during the 70's oil embargo, and I remember him being barely able to get in and out of the thing, lol.
 
Originally Posted By: CATERHAM
Yes that's a pretty comprehensive list of factors contributing to oil consumption and it's worth noting that an oil's viscosity ranked no higher than 31, although running a heavier oil is the first recommendation most jump to to "solve" the problem although at best it just masks the real mechanical issue.


I seriously doubt the number serves as a ranking...

From what I've seen over the last 46 years of vehicle ownership, leaking valve cover gaskets are no doubt #1... Out of approx 175 vehicles owned over the years I've only had two with enough leakage from the front/rear crank seal to warrant repair... One was a '68 302 Ford engine that the front seal self destructed, no fix but replacement... The other was a 1981 diesel Olds, a product called Bearing Seal fixed it with two treatments, drove it 40K mi before I sold the car...
 
Originally Posted By: TFB1
Originally Posted By: CATERHAM
Yes that's a pretty comprehensive list of factors contributing to oil consumption and it's worth noting that an oil's viscosity ranked no higher than 31, although running a heavier oil is the first recommendation most jump to to "solve" the problem although at best it just masks the real mechanical issue.


I seriously doubt the number serves as a ranking...

From what I've seen over the last 46 years of vehicle ownership, leaking valve cover gaskets are no doubt #1... Out of approx 175 vehicles owned over the years I've only had two with enough leakage from the front/rear crank seal to warrant repair... One was a '68 302 Ford engine that the front seal self destructed, no fix but replacement... The other was a 1981 diesel Olds, a product called Bearing Seal fixed it with two treatments, drove it 40K mi before I sold the car...

Valve cover gaskets, timing cover to oil pan gasket area, and like on my sons 96 Corolla 1.8, the crank seal.
His crank seal is leaking so bad that about every year to year and a half he has to replace the crank sensor. The oil builds up on the sensor, causing long hard starts and a CEL. He replaced the factory sensor with an AZ Duralast sensor. Everytime it goes bad he takes it back and gets a new one, under the lifetime warranty.
shocked.gif
 
Originally Posted By: Gokhan
Your experiment is almost certainly in error. Chances are that you overfilled with Pennzoil Conventional, underfilled with GTX, or both. There could also be factors as oil temperature during oil-level check, fuel dilution, etc. In most likelihood you don't have a long-enough OCI with Pennzoil Conventional yet for good data on consumption, as you say it's only been 1000 miles so far. You can't judge much in 1000 miles.

You occasionally will see differences with different brands. I'm not saying there's anything special about Pennzoil Conventional over Castrol in this regard. My old Audi consumed 30 grades fairly heavily. This even included the rather thick GC. The only 30 grade that had noticeably less consumption was Pennzoil Conventional 10w30.

But, like I said, I don't think that means that everyone who has consumption should stick with Pennzoil Conventional and avoid Castrol products. That's simply what I observed in my situation, and I'm sure there are plenty of other anecdotal experiences that go contrary to mine.
 
Originally Posted By: Garak
Originally Posted By: Gokhan

But, like I said, I don't think that means that everyone who has consumption should stick with Pennzoil Conventional and avoid Castrol products. That's simply what I observed in my situation, and I'm sure there are plenty of other anecdotal experiences that go contrary to mine.

Thankfully I've never had "consumption" but somehow I doubt a thicker oil would be a cure for TB!

Sorry Garak, but I couldn't resist!!
 
Originally Posted By: CATERHAM
Sorry Garak, but I couldn't resist!!

Now you've done it. Any engine that experiences "consumption" should now be said to be afflicted with TB. And no, a thicker oil isn't always a cure for vehicular TB. Going up a grade in my old LTD did absolutely nothing for its horrid oil burning.
 
Everyone talks about oil consumption as if it's a bad thing!
What about the benefits?
If it's bad enough you don't have to change the oil any more.
If you have other vehicles in the family the oil burner is a convenient place to dispose of your used oil.
And if you truly get fed up with topping it up just let it run dry.
That will stop the oil consumption once and for all although the remaining engine life will be dramatically shortened. But that is also a good thing, because you're just looking for an excuse to get rid of the old beater anyway.
 
Originally Posted By: CATERHAM
Everyone talks about oil consumption as if it's a bad thing!
What about the benefits?
If it's bad enough you don't have to change the oil any more.
If you have other vehicles in the family the oil burner is a convenient place to dispose of your used oil.
And if you truly get fed up with topping it up just let it run dry.
That will stop the oil consumption once and for all although the remaining engine life will be dramatically shortened. But that is also a good thing, because you're just looking for an excuse to get rid of the old beater anyway.


LOL Back in the '80s I had that issue with a '69 Ranchero with a 302 that had seen maybe a half dozen oil changes in it's life... Was nasty sludged and burned probably a quart in 500 mi, so I used the 20W-40 Pennzoil Racing oil I had drained from my 428 Fairlane it... Funny thing that after it ran maybe 2K mi, oil consumption was greatly reduced and by 5K mi it was using so little I started having to change it...
 
Originally Posted By: CATERHAM
Everyone talks about oil consumption as if it's a bad thing!
What about the benefits?
If it's bad enough you don't have to change the oil any more.
If you have other vehicles in the family the oil burner is a convenient place to dispose of your used oil.
And if you truly get fed up with topping it up just let it run dry.
That will stop the oil consumption once and for all although the remaining engine life will be dramatically shortened. But that is also a good thing, because you're just looking for an excuse to get rid of the old beater anyway.


Caterham, I think an oil burner would be an ideal vehicle for you. Think of it, endless oil mixing ability. Just top off with whatever oil you want to thin out/thicken the current brew inside. A perpetual experiment - until it actually stops burning oil.
 
Originally Posted By: CATERHAM
Everyone talks about oil consumption as if it's a bad thing!
What about the benefits?
If it's bad enough you don't have to change the oil any more.

CATERHAM, do you really believe in this theory? If so, my son has a 96 Corolla that "consumes" about a qt. every 1200 miles. He is using Super Tech High Mileage 10W40 and a Puro Classic L14477 oil filter.
Since he has been using this oil, the 1 qt. "consumption" has gone from about 1K miles to 1200 miles.
The car has 200K miles on it. If this were your car would you follow through with your theory and just add a qt. of oil when needed, than to change it every 5K miles like he usually does?
21.gif
 
When a quantity of oil is used then replaced, you have the effect of approx a 25% oil change(using four quart system as example of course)... Whats going to happen is eventually the oil will have the same high point of contaminants and low point for TBN just before adding and of course low contaminants/high TBN just after adding... In the 1200mi example of per qt 10/12K mi oil changes on dino would likely be fine and could probably go farther...

Ultimately how long between changes will depend on how the oil is being consumed... A leak or worn valve stem seals aren't really causing contamination, while a engine with bad rings and extreme blowby may be coking the oil... The first example may be able to go 20K mi or more, while the other still should have the oil changed by 8-10K mi...
 
Originally Posted By: TFB1
When a quantity of oil is used then replaced, you have the effect of approx a 25% oil change(using four quart system as example of course)... Whats going to happen is eventually the oil will have the same high point of contaminants and low point for TBN just before adding and of course low contaminants/high TBN just after adding... In the 1200mi example of per qt 10/12K mi oil changes on dino would likely be fine and could probably go farther...

Ultimately how long between changes will depend on how the oil is being consumed... A leak or worn valve stem seals aren't really causing contamination, while a engine with bad rings and extreme blowby may be coking the oil... The first example may be able to go 20K mi or more, while the other still should have the oil changed by 8-10K mi...

The leak is coming from the crank seal and valve cover gasket. He is about to have the timing belt, water pump, tensioner, crank seal, VCG, and t-stat replaced.
thumbsup2.gif

If I still lived in FL I would show/teach him how to do this procedure.
frown.gif
 
Originally Posted By: BlueOvalFitter
Originally Posted By: CATERHAM
Everyone talks about oil consumption as if it's a bad thing!
What about the benefits?
If it's bad enough you don't have to change the oil any more.

CATERHAM, do you really believe in this theory? If so, my son has a 96 Corolla that "consumes" about a qt. every 1200 miles. He is using Super Tech High Mileage 10W40 and a Puro Classic L14477 oil filter.
Since he has been using this oil, the 1 qt. "consumption" has gone from about 1K miles to 1200 miles.
The car has 200K miles on it. If this were your car would you follow through with your theory and just add a qt. of oil when needed, than to change it every 5K miles like he usually does?
21.gif


It's a good question. Obviously with such high oil consumption the TBN level won't come close to being depleted. You'll still have to change the oil filter on a regular basis.
There was a used oil analysis a while ago of AMSOIL Signature Series 5w30 with something like 30,000 miles that required topping up every 3,500 miles. The oil was still serviceable with a 3.5 TBN IIRC.
The question was asked then whether the oil really needed changing and no one could think of a technical reason why you should?
 
It comes down to poor engine design/maintence. NONE of my vehicles except my 3.0 413k mile ranger was EVER off the full mark with oil changes under 7k miles. The ranger I believe started consuming M1 because the K&N filter sanded the motor. Even then it was only 3/4 qt every 5k miles. LESSON leaned NO more KN filters
 
Originally Posted By: DrDusty86
It comes down to poor engine design/maintence. NONE of my vehicles except my 3.0 413k mile ranger was EVER off the full mark with oil changes under 7k miles. The ranger I believe started consuming M1 because the K&N filter sanded the motor. Even then it was only 3/4 qt every 5k miles. LESSON leaned NO more KN filters
How does a filter sand your engine?
 
Status
Not open for further replies.
Back
Top Bottom