Engine Oil - A slippery subject Part 2

shipo · January 2008

GC 0W-30, good oil.

The best way I've found to discover induction system leaks is a bit complicated, but usually does the trick. FWIW, I learned this technique as a means of discovering induction leaks on "Boxer" style air-cooled aircraft engines, engines that are notorious for induction leaks.

1) using duct-tape, seal off the exhaust pipe(s)
2) rig up an air compressor and nozzle that can reach your engine (preferably with a real long hose so you won't have to hear it)
3) using lots of duct-tape, rig up the air hose into the air horn down stream of the air filter with an air-tight seal
4) get a large spray bottle and fill it with soapy water
5) turn the air compressor on
6) listen, you may find the bad leaks simply with your ears
7) start spraying your soapy water mixture all over the place and look for bubbles

I hope this helps. Keep us posted. ;-)

Best Regards,
Shipo

smokey75 · January 2008

Is there a limit to how much pressure I use?

shipo · January 2008

It doesn't usually take much, 3 to 5 PSI is going to be plenty. ;-)

Best Regards,
Shipo

wtd44 · January 2008

I know this is counter-cultural on this forum, but! :shades:

Were it me, I'd go for mineral based top quality oil and 3K OCIs for a couple laps and by then I would have acquired my new ride, and the Patchgrinder would be titled to someone else. They are good vehicles (mine was a 1998) and 100K is not excessive, so my point is simply a different view of the situation.

shipo · January 2008

I'm very curious, the Amsoil that you were using, was it the "100% Synthetic 5W-30 Motor Oil (ASL)" which is supposed to be able to go 25,000 miles, or were you using the "Extended Life 5W-30 Synthetic Motor Oil (XLF)" which is supposed to only last 7,500 miles?

I ask because I've never even remotely believed the Amsoil claims of 25,000 miles on the ASL product, and have never even seen a UOA that came back even remotely positive with anything over 15,000 miles on it. That said, being nearly exhausted after less than 6,000 miles is shocking even to me, the consummate non-Amsoil fan. :P

Best Regards,
Shipo

smokey75 · January 2008

It was the Amsoil 100% Synthetic 5w-30 oil.

shipo · January 2008

Thanks.

Best Regards,
Shipo

smokey75 · January 2008

And although the GC 0w30 is a great oil... I still don't expect to see very different results until I solve my problem.

shipo · January 2008

Agreed.

tired_old_dave · January 2008

THE oil forum has been interesting lately. Enjoyed the aviation oil thread. Finally, talk of the rings (compression and oil), starbursts and warranties, and the like. For years now you can hear mechanics talk about the lean engines, lean for emissions and mileage, lean and hot running without the cooling effect of 'extra' gas, and haven't heard about gm top lube in some time.

Using my free synthetic oil now, miss the good stuff that cleaned everything out and let the motor purr.

A thread at THE oil forum a while back mentioned 1 qt of oil useage versus 3 qts per 10k miles seemed okay. How many vehicles on the road 100-200-300 million, all okay to burn oil.

shipo · January 2008

"For years now you can hear mechanics talk about the lean engines, lean for emissions and mileage, lean and hot running without the cooling effect of 'extra' gas, and haven't heard about gm top lube in some time."

...without the cooling effect of 'extra' gas??? Ummm, sort of. While it is true that the further you move the air/fuel mixture away from stoichiometric (on either side), the cooler the resultant peak cylinder temperatures become, however, it isn't so much that extra gas cools as it is that the extra fuel (or extra air in the case of a lean mixture) slows down the flame front, and as the speed of the flame front slows down, the peak cylinder temperatures and pressures drop.

Best Regards,
Shipo

tedebear · January 2008

How many vehicles on the road 100-200-300 million, all okay to burn oil.

Well, I don't know about ALL vehicles. My bike certainly doesn't burn any oil, unless you count the chain lube.

shipo · January 2008

Is that what he was talking about? Hmmm, if he's saying that it's acceptable for an engine to burn oil once it's started crossing the hundred-thousand mile thresholds, I have to disagree, to a point. My opinion (for what it's worth) is that a properly maintained car shouldn't burn much more oil at say the 200,000 mile mark than it did when it was at 20,000 miles.

Best Regards,
Shipo

wtd44 · January 2008

,,,But don't place a big bet in Las Vegas on that! :P

jeffyscott · January 2008

My kid has had oil pressure light go on a couple times. It goes off when he increases rpm by downshifting. Problem has been diagnosed as oil pump and $300-350 to have it replaced. Before he spends the money to replace the pump, is there any way to determine if the engine has already been damaged?

If it turns out that the engine is not worth putting money into, is there anything he can do regarding oil to keep it going as long as possible...heavier oil? lighter oil? avoid synthetic? use synthetic?

How about oil filters that would have less flow resistance, would that be likely to help?

shipo · January 2008

A few questions:

Who did the diagnosis?
What kind of engine?
How many miles on the engine?
What kind of condition is the rest of the car in?

Best Regards,
Shipo

jeffyscott · January 2008

Diagnosis was by independant mechanic...a VW specialist he has been using. I'm pretty sure he did not take it apart or anything, though.

2.0L, 4 cyl engine. Car is a '96 with original engine and has about 100,000 miles. It is in pretty good shape. Just a few small rust spots and a clean, odor-free interior, new brakes on all 4 wheels, and all 4 tires have a lot of tread (2 are brand new). Prior to this problem would probably be classified as "good" on KBB or "clean" on edmunds.

I think he could sell it himself for at least $3000, if it did not have the bad oil pump. I do not think it would be junked if the engine were to die. He probably would at least put a used engine in and sell it, if that were to happen, since I think it would sell for more than the cost of doing that.

ocwave · January 2008

I have begun using this 15000 oil in fairly new cars/trucks. A prius, suburban and an accord, but am now wondering if it is a good idea. I break even on the $$$$ because I used to change oil every 5000. I am using a regular type fram filter and do not know if the filter will work for 15000 or for that matter the oil. Not sure if Im ready for the new tech oil. I am still stuck in 1972 oil thinking!!!
Any comments?
Thanks

shipo · January 2008

Anything that anybody tells you is going to be mere speculation. The only way you can answer your questions for sure is if you take samples from each of your cars and send them out for analysis. If you do, please post the results here.

Best Regards,
Shipo

shipo · January 2008

Is there any evidence of sludging? I ask because it could be a simple matter of the pick-up screen in the bottom of the pan being clogged. That said, the problem could also be the pump (as already diagnosed) and/or worn engine bearings.

FWIW, I had a car years ago that registered low oil pressure at idle (even when new) when the recommended oil (5W-30 IIRC) was in the pan, however, simply by using a 5W-40 grade oil, the problem went away.

Were I in your shoes, I'd pull the pan at the very least and check the screen. If it looks good, swap the pump. If neither of those two prove to be the problem, then you most likely have worn bearings, and in that case, I'd simply move to a heavier oil (maybe something like the Mobil Delvac 1 5W-40) and drive'er till she drops (which she may never do).

Best Regards,
Shipo

Mr_Shiftright · January 2008

DANGER---STOP!

There's no way one could diagnose a bad oil pump as the cause of low oil pressure without removing it and measuring the clearances of the gears inside.

The reason I suggest caution is that you may end up with an engine taken apart in a shop, only to find out that there is debris in the oil pan, or evidence of worn main bearings, etc., leaving you with a very bad series of choices as you look at the parts of your engine sitting on the workbench of the mechanic.

After checking the actual oil pressure with an mechanical testing gauge, I'd check for debris and bearing material in the oil before tearing down the engine.

I would also stop driving the car immediately.

tired_old_dave · January 2008

Try not to post long tirades. That reference was to a read at bitog about three quarts, one quart, newer modified crankcase breathing, and on and on. Do not find consumption of oil acceptable. Like low noack numbers, high viscosity, valve guides/seals that last, good sealing compression and oil rings, and everthing else that keeps the oil in the lubrication side and combustion in the exhaust. How much 'oil burning' (does synthetic burn) before a catalytic converter is compromised. Why do some states still have pollution inspections, when even that system can be circumvented, and oil burners are everywhere.

shipo · January 2008

Dave, once again I gotta say, :confuse:

wtd44 · January 2008

A fast test of some interest on a VW engine might be to try some 10W-40 and see if the light goes out; and if it does, determine if it stays out under all driving circumstances. The chance that an extinguished light is the end of the problem has some actual potential, but may or may not meet your criteria for "peace" of mind concerning the engine condition. I'd also say you'd be well advised to consider the ideas presented by Shipo and Mr. Shiftright.

jeffyscott · January 2008

Definitely considering and appreciate all ideas. I was a little confused by mr. shiftright's comments about the engine being taken apart, though. From what I've read, getting to the oil pump only requires removal of the oil pan...I'm guessing maybe some cars require more disassembly for this job?

The odd thing is the oil pressure light has apparently not come back on again since the original incidences.

Today we looked in where oil cap is to see if things looked sludgey, looked pretty good in that regard, but there were signs of moisture...creamy slurry on bottom of oil fill cap, I assume this is from condensation. We have had some extreme cold and my son has very short trips...like 3 miles, so not too surprising.

Another place is investigating things tomorrow. Guy there told my son he did not think it was the pump, since the light has not come back on.

Mr_Shiftright · January 2008

Oh sorry for the confusion. What I mean was, suppose they pull the pan, pull the oil pump and find it all full of metal shavings? Then you have a non-running car with the parts of the motor on the floor?

Not a good way to make a decision on what to do next. The term "held hostage" comes to mind.

I think that if the oil pressure isn't checked with an accurate screw-in gauge, then the mechanic is being reckless in suggesting he tear into your engine. I just don't like this approach to your problem. It's called "guessing".

jeffyscott · January 2008

I think the place he has it at today is more careful with their diagnoses and better about explaining things, etc.

I had assumed the first place had measured the pressure, as I don't know how else they would have any idea what the problem is. But I don't know for sure what they did...

Even if you measure the pressure that does not tell you the cause of the low pressure...or does it? If the filter or pick up tube is clogged or even if the cause is engine wear, wouldn't those problems still register low pressure on a guage?

Mr_Shiftright · January 2008

The gauge, being analog, not only tells you the actual pressure but HOW the pressure is behaving, which can also be an aid in diagnosis.

For instance, does the pressure drop as the car gets hot or does it stay low all the time? How much of a drop? Does revving the engine increase the pressure at all and by what increment?

If the oil screen is so clogged as to cause oil pressure loss, then that's only the symptom, not the cause. What on earth has caused this degree of sludge in the engine?.

Oil pump failure might also be only part of the issue or all of it. You can replace the pump but having driven with low oil pressure might have done some damage. If the main bearings are worn, the car will not hold good oil pressure.

So even if the pump were worn out and replaced, I'd do an oil analysis and see what material is in there. A lot of bearing material being detected is a sign of damage and a premature failure not too far down the road.

Anyway, I hope it's nothing too bad. I just didn't want to see you with the terrible scenario of an engine laying in pieces at your feet and the mechanic saying "so, what do you want to do now?" as if you had a good choice at that point.

wtd44 · January 2008

Your hostage warning is an excellent point!
I wonder if an excessive low level of oil (volume) existed when the temporary light-on episodes happened. I suspect really low oil might turn the light on.

tired_old_dave · January 2008

Used Mobil 1 for decades. Jumped from mobil 1 5w30 to the boutique oil and now to the free, after rebate, synthetic valvoline. The motor doesn't clatter and feels strong. Don't know if the half quart of the boutique oil left in with the oil change has any bearing and don't care. Two out of three keep the pushrod quiet and strong. One better and costlier than the other but both better than the synthetic 'standard?'.

jeffyscott · January 2008

I just didn't want to see you with the terrible scenario of an engine laying in pieces at your feet and the mechanic saying "so, what do you want to do now?" as if you had a good choice at that point.

You were right on target with that. It is a good thing he went for a second opinion and more careful diagnosis. The good news is there is no reason to pay for a new oil pump, the bad news is the oil presure is low due to engine wear. Not sure, but the old oil the previous owner had in it may have been 5 or 10W-30. He went with synthetic, I believe mobil1 10w-40 is what was put in.

Hopefully this, perhaps, heavier oil will be enough to keep it going without a recurrance of low oil pressure, as shippo and wtd have suggested it might. If not would the next thing to try be somethingW-50? Being in wisconsin, would a 5w-50 (there is a castrol syntec of this grade) or 10w-50 (if anyone makes this) be better than a 15W-50 (eg. mobil1 or penzoil)?

shipo · January 2008

I'd opt for the 5W-50 waaaay before I opted for the 15W-50, especially in the winter months. ;-)

Best Regards,
Shipo

jeffyscott · January 2008

Okay, so the "thicker" W part is not advantagous in terms of achieving adequate pressure...that is what I would have guessed, that anything is going to be thick enough (or too thick) when cold, but wanted to be sure.

He parks outside where it was -8 this morning. My car, in the attached garage registered 19...but I'm not giving up my parking spot to make 15W feasible for him

.

wtd44 · January 2008

I would remind all that the first number in the "weight" of the oil is the one that states the cold "thickness" of the oil. The thickness of the oil may be the key to keeping the pressure up in the engine when the oil pump is not working hard, like at idle and low RPMs. I suspect you might get good results from 10W-X0 oil, where X is 3 or 4. If the 10W oils are too thick, you'll know it quickly in that cold weather you described, and can then adjust your choices as desired. Do you remember the viscosity improver additives such as STP? Walmart has a house brand of this heavy syrup-like product at a low price. You might use some of it in your 5W-X0 oil to bring that 5 up to a higher value. Actually, the entire process sounds like an interesting project!

shipo · January 2008

While I'm not sure I understand the logic of your post, I will say this; even a 0W-40 oil will be well beyond thick enough to keep the oil pressure light from illuminating when the engine is cold, and once warm, there will be virtually no difference between the rate of flow and the pressure attained between a 0W-40 and a 10W-40.

As for viscosity improvers of the STP ilk, I've torn down way too many engines where that stuff was used to ever be willing to pour a can in any of my engines. Yuck, that stuff make such a slimy (and smelly) mess inside your engine that each time I opened one up, I nearly, ummm, errr, lost my lunch.

Best Regards,
Shipo

jeffyscott · January 2008

I read a little on viscosity and oil grades here:

http://www.valvoline.com/carcare/articleviewer.asp?pg=ccr20040601ov

So a 10W-40 would act like a 10 @ 0C and a 40 @ 100C, while a 5W-40 would act like a 5 @ 0C and 40 @ 100C...but what about in between 0 and 100C?

Would the 10W be a little thicker than a 5W-40 not only at 0, but any temp between 0 and 100C, as the engine is warming up? Would it be enough of a difference to matter?

shipo · January 2008

"Would the 10W be a little thicker than a 5W-40 not only at 0, but any temp between 0 and 100C, as the engine is warming up? Would it be enough of a difference to matter?"

Yes, in theory at least, the 10W-40 will be a tad thicker than the 5W-40, however, once above say 40C the difference is pretty much meaningless. Regarding engines that show a low oil pressure light at idle, typically the light only illuminates once the oil is fully warmed up. Assuming that the engine we're discussing here exhibits that behavior, then a 10W-40 will net you absolutely nothing over a 0W-40 in terms of keeping that light from lighting.

Best Regards,
Shipo

wtd44 · January 2008

My experience (from years ago) was that now and again a particularly worn engine may have the light go on due to the oil sliding too easily around the wide clearances. That is, the oil does not receive enough resistance to develop adequate pressure (at least at idle) to hold the pressure switch (that controls the light) in the off position. Thick oil may reverse this effect. "Viscosity improvers" make oil thick. As to the sanitation aspects of STP in a torn down engine, I won't argue a bit, but will say I have never found STP or any other "motor honey" to be all that offensive. One of the "nice" effects of STP on an old engine about to blow was that the goo stopped a lot of mechanical noise, making the last gasps of the engine a bit more tolerable! :sick:

shipo · January 2008

"My experience (from years ago) was that now and again a particularly worn engine may have the light go on due to the oil sliding too easily around the wide clearances. That is, the oil does not receive enough resistance to develop adequate pressure (at least at idle) to hold the pressure switch (that controls the light) in the off position. Thick oil may reverse this effect."

Agreed, hence my recommendation of going with a 5W-40 oil. Adding STP or any other highly viscous additive isn't the same as adding viscosity improvers (which make a thin oil act like a thick oil when its hot), it's more like adding viscosity to the overall oil, and that could spell disaster for an engine located in Wisconsin that needs to cold-start at temperatures well below zero.

Best Regards,
Shipo

jeffyscott · February 2008

Regarding engines that show a low oil pressure light at idle, typically the light only illuminates once the oil is fully warmed up. Assuming that the engine we're discussing here exhibits that behavior, then a 10W-40 will net you absolutely nothing over a 0W-40 in terms of keeping that light from lighting.

That makes sense, that the main issue would be: what is the pressure when the oil is at its thinnest and the engine is at its lowest rpm...since that is when the oil pressure would be lowest. The day the light came on it was running above idle...about 1500 rpm, and pretty well warmed up. Still has not recurred since that day and my kid says it seems to be running better overall since his oil change.

Maybe the old (probably 5 or 10W-30) conventional oil had just gotten too worn out after 5 months of mostly short trips (2-3 miles) to maintain pressure in his particular, somewhat worn, engine?

shipo · February 2008

"Maybe the old (probably 5 or 10W-30) conventional oil had just gotten too worn out after 5 months of mostly short trips (2-3 miles) to maintain pressure in his particular, somewhat worn, engine?"

Ouch! Trips of two to three miles do two bad things to oil, 1) introduce lots of condensed water into the oil but never get the oil hot enough to boil said water off (prolonged water in the oil has a tendency to create acid), and 2) given that the engine is cold (especially in Wisconsin), the engine runs very rich while it is warming up, and as such, fuel dilution is a problem.

For that car I'd be inclined to use a heavier oil and change it more often (maybe every three to four months). The diesel engine oil that I recommended several posts ago (oil that also works very well in gasoline engined cars) would be just about perfect for the job. Another option would be to make sure that the car gets out on the highway at least once a week for a good half of an hour.

Keep us posted.

Best Regards,
Shipo

Mr_Shiftright · February 2008

Once you've had to tear down an engine that 's full of STP, you might change your mind. It's dreadful stuff. I think it makes the situation worse, not better. However, it's great to mix up with some oil as a dipping sauce for new shell bearings! :P

jeffyscott · February 2008

Yeah, we are kind of hoping the problem was caused by gasoline diluting/thinning the oil.

The new oil is 10W-40 and synthetic, I think that means the water will not create acid. The old oil was from previous owner that had changed just before selling...he had already been planning on going to synthetic. Next fall he will be going to the local tech college, that is about an 8 mile drive each way, so that should help some.

shipo · February 2008

Hmmm, 10W-40 huh? Personally I'm thinking that that's a tad on the thick side for a Wisconsin winter. I'd be more inclined to use a 5W-40 or even a 0W-40 for your environment.

Best Regards,
Shipo

wtd44 · February 2008

I would do exactly what you have set out to do. If the 10W-30/40 is too thick, you'll be the first to know it, and I am sure you will take appropriate steps! And to Shipo: You are nitpicking here. Did I really fail to set the stage so that you would understand that by "viscosity improvers" I was referring to thick petroleum additives? I guess not... :mad:

jeffyscott · February 2008

Some use 10W some use 5W around here, it is southern WI. I've used 5W ever since that started being the manufacturer recomended oil. Although, at first I thought "what is this crazy 5W stuff", I was always used to seeing 10W-40 and 10W-30 as the "normal" oil to use.

It does not get to -20 very often, I think it's been many years since the last occurance. So if this chart from http://www.aa1car.com/library/oil_viscosity.htm is correct 10W is okay. They do talk about wider range oils being more subject to breaking down, so maybe that is why he (the mechanic) used 10W...or else it is just that it is cheaper

.

shipo · February 2008

A couple of points:

1) The chart shows 10W-30 going down to -20 Fahrenheit, I'm thinking that that chart is for conventional oil, and that -20 for a conventional 10W-40 is probably below the minimum safe point for usage. FWIW, I was living in Chicago back in the mid 1980s when the temperature got down to twenty something below (on the thermometer, wind chill was MUCH lower). During that time (two consecutive weekends at -20 or lower, IIRC), I had the only car that would start of any of my friends. Why? I suspect it was because they were all using 10W-30 in their cars and I was using a 5W-30 Mobil 1.

2) The discussion of wider range oils breaking down is only valid for conventional oil and possibly Group III pseudo-synthetics as well. Oils like PAO based 0W-40, 5W-50 and even 5W-60 are so naturally stable due to their synthesized molecular structure that they don't need any viscosity improvers to allow for such a wide range, and as such, they don't break down (i.e. thin out) like conventional oils. In fact, as true synthetic oils age, they actually have a tendency to thicken a bit.

Best Regards,
Shipo

jeffyscott · February 2008

-20 for a conventional 10W-40 is probably below the minimum safe point for usage.

Did you mean to imply by this that a synthetic 10W would perform better at that temp than conventional would. My kid has said his car seems easier to start and happier when cold with the synthetic 10W-40 than it did with the conventional 10W-30. (I agree with you, though, I'd go with 5W, myself even if 10W would be "good enough".)

I think the coldest we have hit in my 20+ years in the Milwaukee area is -22. We did get to about -10 this year, which was the coldest in quite a while, I believe.

Based on that chart, that shows a 10 degree difference in min temp, I would guess there is about a 10 degree differential for the same viscosity...so for example 5W at -10F is like 10W at 0F and 5W at 0F is about the same viscosity as 10W at 10F, is that about right?

wtd44 · February 2008

Happily, it seems that the problem is well in hand, and probably solved, although you may end up dropping down to 5 from the 10 should that come to be desirable. As the "A team" guy used to say on the tube, "I love it when a plan comes together like this."

shipo · February 2008

"Did you mean to imply by this that a synthetic 10W would perform better at that temp than conventional would."

Yes, absolutely. ;-)

"My kid has said his car seems easier to start and happier when cold with the synthetic 10W-40 than it did with the conventional 10W-30."

Makes complete sense.

"Based on that chart, that shows a 10 degree difference in min temp, I would guess there is about a 10 degree differential for the same viscosity...so for example 5W at -10F is like 10W at 0F and 5W at 0F is about the same viscosity as 10W at 10F, is that about right?"

Yes, all else being equal (which of course it never is), your description above is pretty accurate.

Funny thing, I got into an oil viscosity discussion a few weeks ago (on a different board) when I was being taken to task for running Mobil 1 0W-40 in our cars that call for 5W-30 conventional oil. The individual challenging me effectively told me that I was being an idiot because the 0W-40 has a higher "cold" viscosity than does conventional 5W-30, and that my engine was probably being damaged because my oil was too thick to provide adequate lubrication following a cold start.

When I pointed out to him that the "cold" viscosity rating he was using for his argument was taken at 40C and that in the history of my town here in New Hampshire, we've NEVER gotten as hot as 40C, he changed his tack and explained that viscosity changes in a linear fashion and in lock step with its temperature. He then proceeded to plot the viscosity "curves" (which of course were straight lines) based on the 40C and 100C viscosities to prove his point.

I countered by pointing out the effective gel point for a typical 5W-30 conventional oil was just below -20F, meanwhile the gel point for my 0W-40 steps in at about -65F. Indirectly that proves that viscosities (at least those of synthetic oils) are not linear, and that the viscosity curves or our two subject oils MUST cross.

With the above realization in mind and the fact that obtaining true "cold" viscosity numbers is virtually impossible due to the way oil statistics are published on the various Product Data Sheets, I've been thinking of building a temperature controlled apparatus that will allow me to repeatable test the flow properties of oil at temperatures of say ten degree increments. For those of us who live in cold climes, seeing a good representation of how various oils flow at various temperatures could be invaluable in properly choosing the correct oil for our engines. Hmmm, might be a fun project. ;-)

Best Regards,
Shipo

Engine Oil - A slippery subject Part 2

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