 |
|
shifter11 wrote:
[quote]Ranger, instead of trying to change the rules to accommodate for a few motors going south on you… why not just run thicker oil like the rest of us?
[/quote]
oh, don’t mind Ranger. He’s mostly harmless.
It’s just his hobby to dig into a really tight hole and get obsessed in trying to make it wider.
If you let him burn out, he usually moves on to another hole.
I enjoy reading his adventures.
Ive been working on e 30’s( as a professional) snice they were new, and back then we put 20/50 in them, the 5w 30 that BMW sells didn’t even exist! The 5 w 30 is for the newer cars! The M30’s I run also call for 20/ 50 , I tried a thinner weight oli several years ago and ended up thoughing a rod out the side of the block and catching the hill from T1 to t 2 at road ATL on fire, back to 20 /50!!
rrroadster wrote:
Not that I’ve noticed. The only affect that I’ve seen is an increase if hot oil pressures, which was the goal of adding STP.
shifter11 wrote:
[quote]Ranger, instead of trying to change the rules (some of your other threads) to accommodate for a few motors going south on you… why not just run thicker oil like the rest of us?
What data has led you to your lower viscosity decision? Instead of telling the rest of the world that the tried and true doesn’t work, why not tell us why your new data does?[/quote]
That’s a little uncharitable.
I initiated a discussion on how we might improve our oiling system because it’s my perception that our series has an unusual number of bearing failures. If you don’t believe that the bearing failures are occuring, then ignore the thread. If you do believe that our numbers of bearing failures are a little high, well, then for initiating the discussion and doing some research, you’re welcome.
Re. running thicker oil like the rest of us. Maybe everyone is running thicker oil, maybe not. Maybe those running xW50 have had fewer bearing problems, maybe not. If we are going to find truth, we need to have better data.
Just because other folks are doing something doesn’t make it right. It might well be right if the other folks are successful. Or they might be successful because they are doing something else right. Some folks are perfectly happy to follow without understanding. More power to them. I want to understand.
Just the fact that we’re talking about viscosity and not high temp shear indicates that we’ve really not paid much attention to oil characteristics.
I’m not telling folks that “what is tried and true doesn’t work”. I’m just providing food for thought. Example: I posted a quote from Corner-Carvers here the other day from some (non-BMW) guy that was able to figure out that his oil pickup sucked air routinely on hard corners, but that his oil pressure gauge never showed it. That could be happening to us and we wouldn’t even know it. And it wouldn’t matter what kind of oil you were running. I believe that things like this are worth considering and discussing. It isn’t about me, it’s about us.
Re. the oil data. I’ll post my oil spreadsheet and write up some explanations. And I’ll try to find some of the old BobIsTheOilGuy threads. I gotta warn folks tho that oil and is surprisingly complex. I’m a mechanical engineer but I don’t have any background in lubrication and when the experts get going at BobIsTheOilGuy, it can be hard to follow.
What I’m trying to say here is that in the oiling thread I’m not attempting to make a bunch of assertions. What I’m trying to do is ask questions.
Does our series have a history of bearing problems? If so, what are the causes? Only by understanding the causes can we solve them.
What can we do to solve the oiling problems, if any?
And now that the type of oil question has been thrown into the fray, what oil characteristics are optimum for our bearing design? The previous post is the first time I’ve seen someone actually support the assertion that 20W50 was the original recommended oil. That’s significant. I’d still like to find out what the tribiologists have to say about the oil characteristics that our bearing design should tho.
Could the bearing problems be just a fact of the age/condition of alot of these engines? Add in the fact that they are being taken to 6000 rpm over and over, some of them for several hours in enduros, and there lies the problem. It’s just mechanics. Things are going to wear out, and when used at the limit of their design, they wear out faster. There may be nothing you can do to prevent it from happening over and over again. Things get old and break, that’s why they invented Viagara.
In professional racing series, no one is running around the track with engines with over 100,000 miles on them I would bet. But they probably still have bearing failures from time to time. What’s my point? I’m not sure.
Scott, Step back and think about the number of people that are not having oil system problems. Have you considered the possibility that your assumptions may not be correct?
drumbeater wrote:
[quote] Things get old and break, that’s why they invented Viagara.
[/quote]
LOL! :lol:
My $0.02…
Ranger is a good guy. I really enjoyed hanging out with him last time at CMP (and watching him rally the troops for a motor swap at the previous CMP race). He simply has a personality quirk that compels him to find things out or do things for himself.
I don’t discourage our own Don Quixote from tilting at the motor oil windmills. I have learned a bunch about our motors and oiling in general as I have tried to keep up with his research and experiments.
That being said, I think the reader (who may be considering SE30 as a series) deserves to know what lengths you have to go to in order to have a servicable M20 engine. I don’t personally know of any motors that spun bearings provided that they were:
If anyone knows of any motors that have let go under those conditions, please speak up.
I hope Ranger’s oiling system upgrades work well and solve his problems. I also hope they are overkill.
I know Ranger got burned by a shop, but I still maintain that for most of us having a shop do the work really IS the cheaper way once you consider travel and entry fees for just a single lost weekend. Their expertise is damn near free. But invauable!
Steve D.
drumbeater wrote:
[quote]Could the bearing problems be just a fact of the age/condition of alot of these engines? Add in the fact that they are being taken to 6000 rpm over and over, some of them for several hours in enduros, and there lies the problem. It’s just mechanics. Things are going to wear out, and when used at the limit of their design, they wear out faster. There may be nothing you can do to prevent it from happening over and over again. Things get old and break, that’s why they invented Viagara.
In professional racing series, no one is running around the track with engines with over 100,000 miles on them I would bet. But they probably still have bearing failures from time to time. What’s my point? I’m not sure.[/quote]
Maybe the bearing failures are only a result of the motors being old. But motors with new bearings have failed too. Of course other variables might have played in. Maybe xW30 was a bad oil choice and that contributed to failures. Maybe someone didn’t run a qt high, maybe they didn’t have an crankscraper, maybe bearings, crank or journals weren’t quite right. I don’t know. There’s a lot of variables.
But I do know that if we are curious as to why our rate of bearing failure seems to be a little high, we might find some answers that help us reduce the failure rate. On the other hand, if we’re not curious, we’ll find out nothing.
If I had to guess I’d say that, because of the Autobahn, our oiling system was designed to support the motor at high loads for long periods. That’s not the same as racing, but it’s a good fraction of it. I’d also figure that our motor was not designed to support 1g turns every couple of seconds. I can’t help but wonder if our oil pickup isn’t sucking air more often then we think. I’d call the oil choice issue secondary.
Scott, Couple of questions for you. Where did you get the idea that the oil level should be overfilled by a quart? And what leads you to believe that the oil pump is sucking air through the turns?
Here are a few facts to throw into your thought process. My motor is on the third year. I’ve never run anything except 20W50 and I do not overfill it. The first two years I ran without a crank scrapper.
Gasman wrote:
It’s not clear that there is a systemic oiling problem in our series. It would be really hard to collect complete data on the issue, and we’ve not even collected crappy incomplete data. But the anecdotal evidence of a problem is strong enough to at least create some interest in the issue, isn’t it?
At what point is a problem systemic? For example: We perceive our sway bar mount points as weak so we reinforce them. How many of us actually broke OEM sway bar mount points? A few folks probably broke them early on, they decided that the OEM design wasn’t up to racing, so they reinforced them.
How many similar failures have to occur before someone scratches their head and says “y’know, maybe there is a weakness here”? “Maybe” doesn’t require much of a threshold, that’s all I’m saying.
Re. assumptions. Of course I’ve considered that my assumptions might be incorrect. The initial ideas about a problem are always wrong. Later, some truth is sometimes found, and sometimes not. But folks were talking here in the forum about losing their bearings long before I came along and started driving everyone crazy.
Ranger wrote:
[quote]Gasman wrote:
It’s not clear that there is a systemic oiling problem in our series. It would be really hard to collect complete data on the issue, and we’ve not even collected crappy incomplete data. But the anecdotal evidence of a problem is strong enough to at least create some interest in the issue, isn’t it?
I would say no.
At what point is a problem systemic? For example: We perceive our sway bar mount points as weak so we reinforce them. How many of us actually broke OEM sway bar mount points? A few folks probably broke them early on, they decided that the OEM design wasn’t up to racing, so they reinforced them.
I haven’t had a problem with this either.
How many similar failures have to occur before someone scratches their head and says “y’know, maybe there is a weakness here”? “Maybe” doesn’t require much of a threshold, that’s all I’m saying.
Re. assumptions. Of course I’ve considered that my assumptions might be incorrect. The initial ideas about a problem are always wrong. Later, some truth is sometimes found, and sometimes not. But folks were talking here in the forum about losing their bearings long before I came along and started driving everyone crazy.[/quote]
As John said, most of the motors have 200K on them.
FWIW: I have nothing but what the motor came with when it rolled off the line. I use 20/50 or 15/40 or 15/50 depends on what I grab off the shelf :blink: I’m going into my 3rd season of racing… no issues (to date) and my motor is strong.
I’m hoping all the stuff Mr. Gress is doing is overkill
Ranger wrote:
[quoteMaybe the bearing failures are only a result of the motors being old. But motors with new bearings have failed too. Of course other variables might have played in. [/quote]
They are still 200,000 mile motors with new bearings. Agian, even Viagara only last for a few hours.
Gasman wrote:
[quote]Scott, Couple of questions for you. Where did you get the idea that the oil level should be overfilled by a quart? And what leads you to believe that the oil pump is sucking air through the turns?
Here are a few facts to throw into your thought process. My motor is on the third year. I’ve never run anything except 20W50 and I do not overfill it. The first two years I ran without a crank scrapper.[/quote]
My perception is that the common wisdom is to run oil 1qt high. I buy into the idea.
There’s been numerous reports of oil pressure dropping during long hard turns. I haven’t personally seen this, but I only scan my gauges a couple times per lap. I’m hoping my oil pressure warning lights help me spot this in the future.
The idea of the oil pickup running briefly dry strikes me as very plausible. Several engine folks I’ve talked to over the past few months made the point that the oil volume in the oil pan is far far more energetic then most folks would imagine. Without significant horizontal baffling, there is apparently very little still oil volume if there are serious driver inputs going on.
We have no idea how quickly our gauge depicts oil loss in the galley. My perception is that auto gauges, sensors and sensor locations result in readings that are fairly “buffered”. That is to say, they don’t reflect short duration changes. What if our oil pickup running briefly dry was common? How would we know?
It is terrific that you’ve not had oiling system problems yet. And I hope that it continues that way the same way I’d hope good fortune to any buddy. But the number of anecdotes from folks that had to replace their bearings still catches my attention.
To everyone: Don’t get me wrong…I’m not jumping up and down and clammering for attention on the issue. It’s just a discussion. I’m just curious.
Not saying it’s wrong, but you are almost taking a shotgun approach at dealing with a perceived oiling issue.
Is it type of oil? Oil temperature? Bearing clearance? Pump health? Oil volume? Pan design? Combination thereof?
Seems like a lot of time and money invested in a problem that may end up being overkill. Although, it may be the only way to be sure the problem doesn’t resurface prematurely.
Do you/will you have data showing oil pressure/temperature related issue on track?
Steve D wrote:
[quote]
I don’t discourage our own Don Quixote from tilting at the motor oil windmills.
Steve D.[/quote]
I neglected to mention…that was a great metaphor.
Ranger wrote:
[quote]Gasman wrote:
[quote]Scott, Couple of questions for you. Where did you get the idea that the oil level should be overfilled by a quart? And what leads you to believe that the oil pump is sucking air through the turns?
Here are a few facts to throw into your thought process. My motor is on the third year. I’ve never run anything except 20W50 and I do not overfill it. The first two years I ran without a crank scrapper.[/quote]
My perception is that the common wisdom is to run oil 1qt high. I buy into the idea.
What exactly is “common wisdom” and why did you buy into it; is it the old theory if some is good, more is better?
There’s been numerous reports of oil pressure dropping during long hard turns. I haven’t personally seen this, but I only scan my gauges a couple times per lap. I’m hoping my oil pressure warning lights help me spot this in the future.
You may need a high output alternator to handle all of your warning indicators.
The idea of the oil pickup running briefly dry strikes me as very plausible. Several engine folks I’ve talked to over the past few months made the point that the oil volume in the oil pan is far far more energetic then most folks would imagine. Without significant horizontal baffling, there is apparently very little still oil volume if there are serious driver inputs going on.
Why does this strike you as “plausible”. Oils have adhesion and viscosity ratings for a reason, which is why you want them to be heavier…not lighter as you suggest.
We have no idea how quickly our gauge depicts oil loss in the galley. My perception is that auto gauges, sensors and sensor locations result in readings that are fairly “buffered”. That is to say, they don’t reflect short duration changes. What if our oil pickup running briefly dry was common? How would we know?
And a warning light is going to change this?
It is terrific that you’ve not had oiling system problems yet. And I hope that it continues that way the same way I’d hope good fortune to any buddy. But the number of anecdotes from folks that had to replace their bearings still catches my attention.
To everyone: Don’t get me wrong…I’m not jumping up and down and clammering for attention on the issue. It’s just a discussion. I’m just curious.[/quote]
OriginalSterm wrote:
[quote]Not saying it’s wrong, but you are almost taking a shotgun approach at dealing with a perceived oiling issue.
Is it type of oil? Oil temperature? Bearing clearance? Pump health? Oil volume? Pan design? Combination thereof?
Seems like a lot of time and money invested in a problem that may end up being overkill. Although, it may be the only way to be sure the problem doesn’t resurface prematurely.
Do you/will you have data showing oil pressure/temperature related issue on track?[/quote]
I don’t know what it is. But I’ll continue to poke around and see if I stumble across clues.
I could connect an oil pressure sensor to my Traqmate, but I’ll wait and see what the oil pressure warning lights do. And I’m a little max’d out on car projects right now. I need to get my shit running before I worry about putting icing on the cake.
The only thing I really did to address my perceived oiling problems is the Accusump and pressure warning lights. I avoided the big expenses by using steel hydraulic fittings instead of aircraft grade red and blue anodized aluminum. The Accusump itself came from Craigslist.
The other work on the oiling system was along the lines of "well, if I’m tearing into the oiling system, what other oiling system mods might be worth doing.
The more I think about it, the more I lean towards brief uncoverings of the oil pump pickup as the most likely problem child. So I’ve high hopes that the Accusump is going to be a significant addition.
Time invested is ok as long as learning occurs.
Re. 1qt high. I think that it was Robert Patton that first told me about running a qt high. Other experienced types have echo’d this. It makes sense to me because I think that it would help keep the oil pickup covered. More isn’t necessarily better. Too much and the crank will froth the oil.
Re. Why does the oil pick up sucking air strike me as plausible. Because when I imagine oil flying around the bottom half of the engine pan due to rapid driver inputs I can easily imagine the oil pickup becoming uncovered briefly.
And the oil gally becoming unpressurized strikes me as more problematic then differences in oil high temp shear. There is a “wedge” of oil between the bearing surfaces that has to be maintained. But if the input pressure of the oil drops, the wedge fails.
Maybe running xW30 was a contributor to some of the bearing failures, we don’t know. We also don’t have high temp shear numbers to compare 1987 20W50 to 2009 synthetic xW30.
And we still don’t have any of the science behind that 20W50 recommendation. It’s not the engineers that are recommending xW20 oils for modern cars today, it’s the marketing dept and their pursuit of mpg. It’s not the engineers that recommended neutral camber for our front wheels. We should not uncritically accept recommendations. We should temper recommendations with research and experience. And yes, I know that there’s anecdotal support (experience) for 20W50.
Oil viscosity and adhesion do exist for a reason.
If 20W50 is the best choice, then we should attempt to understand why.
Re. “and warning lights are going to change this?” Warning lights might tell me that I’m routinely, albeit briefly, experiencing low oil pressure at the pump outlet. It shouldn’t affect me because the Accusump is just before the oil galleys, but it would still help us as a series understand (or rule out) a possible cause.