by pass oil filters

[H3Jim]

Regarding Seans problem of his engine being dirted out.

Would a bypass filter have cleaned all the silicate out before Sean had put very many miles on his engine?  Its true, the dirt all went in the air filter, and would be doing damage as it made its passes around the engine before it could get filtered out.  But it would be filtered out, and before too many miles had passed, way before the next oil change.

So the question for some of our more knowldgeable bus nuts out there, Would a bypass flter have helped Sean get more miles from his engine before requireing a rebuild?

Is it good insurance for those of us that occasionally drive on dirt and sand, if our air intakes don't stop all the dirt, do the bypass filters get it all, soon enough?

[Buffalo SpaceShip]

Jim, it 'sure wouldn't hurt', as they say. Some folks swear by the bypass filters, and it's hard to doubt the technology behind them. I guess most outfits use them to extend the oil changes, but those big "diapers" should filter out a lot more stuff than the full-flows... including silicates, I would presume.

Hmm... anyone seen a good supplier of these? My old GMC Maint. Manual lists them as an option way back in 1978 (which didn't come on my coach, but I had one on my old '68 Fishbowl). Sounds like good insurance to me!

Brian B.

[tekebird]

I have a brand new bypass filter system if anyone is interested. 

note: most bypass filters I have seen filter very fine particles but they do not flow opil like a standard filter.  only a % of the oil passes per pass vs a standard filter that passes all the oil every time it cycles by

few years ago there was a test in one of the trucking mags. incidently using the filter I have......they drove the same oil, synthetic I beleive for 1,000,000 miles with only oil samples taken.  it speced fine at 1,000,000 miles.  not that I would recommend that but it does say something.

It was an independant magazine run test.....and although the filter system was mentioned......I have yet to see an advertisement for it in the magazine

[Sammy]

Jim, I don't think it would have made much difference in this case.
The dirt was drawn in from the air intake, into the turbo (if he has one) and blower, into the air box.
Some dirt might have gotten scavenged out, some obviously was drawn into the cylinders causing failure.
Sean mentioned that they found stuck rings in the piston lands - most likely from dirt.
Some dirt then definitely got past the piston rings, into the engine oil, and the rest is history.
Periodic inspection of air intake system is critical. I know its a pain in the a** most of the time to do this on converted coaches, but it could save alot of grief. Everyone should add it to thier lists of things they hate to do, but need to do. 

[TomC]

The reason some of the modern engines with synthetic oil can go 1 million miles with no oil change, is they burn so cleanly, they produce very little soot both out the tail pipe and invading the oil.  With two strokers, we can't do that-even with DDEC because of the dirty nature of the two stroke. 
The main reason for the by pass is to filter a portion of the oil continuously (all oil gets through the filter at least once an hour) and to lengthen the time between oil changes.  With our mostly low mileage per year, the best is just to change the oil once a year, or do it by having the oil analyzed.  As Sean said, he believes the oil was never really analyzed properly, or else his dirt invasion could possibly been detected sooner.  I personally do about 3-5000 miles a year.  My last oil change was a 2.5 year interval, but with oil analysis every year.  Even at the end of two years, the oil was alright, but older filters make me nervous since they can disintegrate after time (the specific amount of time hasn't been determined). Good Luck, TomC

[Sean]

... Sean ... believes the oil was never really analyzed properly ...

Just to be clear:  It was not analyzed at all.  When I gave the shops the list of things I wanted done, including changing the engine oil, I specified that samples should be drawn for analysis.  Each time, it was a case of walking up to pay the bill, and asking when I might expect the analysis report, and having the shop say "oops... we forgot about that."  At which point, of course, the old oil has already been dumped into a vat with every other customer's used oil, so no way to go back and get any of it for testing.

I try to respect the rules, whether enforced or not, in most shops prohibiting customers in the work area.  Even if a shop doesn't claim such a rule, mechanics hate it when customers are constantly looking over their shoulders.  There's an old adage about shop rates:  Standard, $50/hr -- If you watch, $75/hr -- If you help, $100/hr.  We consider ourselves lucky if a shop let's us sit in the coach while they work, as opposed to booting us out and into a waiting room or customer lounge.  In the future, though, I will be more attentive when it comes to draining the oil, and make sure they pull that sample.

On the subject of bypass filtration, I favor the Gulf Coast O-1.  Unfortunately, I can't imagine where I would even put such a monster in my engine bay (and the O-2, which is nominally specified for engines over 250bhp, is completely out of the question).  While GC will be happy to sell you "elements" for this, it readily accepts Bounty Big Roll paper towels, which is what everyone including the US government uses.  But, as noted above, the damage to my engine came from the dirt in the combustion chambers.  Sure, some of that ended up in the oil, but, frankly, we changed the bearings only because they're cheap and you might as well once the rods are out -- the wear was well within spec.  FWIW.

Whenever we are done with the bus, we're buying a boat, and you can be sure it will have a Gulf Coast bypass filter on it.  Getting rid of old engine oil is a major hassle on a boat, and we'll want to go to extended drain intervals through bypass filtration, synthetic base stock, and regular analysis.

-Sean
http://ourodyssey.blogspot.com