Hey guys (and gals), I am on an RV forum and they have a section for Cummins powered RVs. There is someone on there that for what ever reason seems to try to contradict anything I post there. Here are some of his statements (in bold) about idling:

"X2, The only thing you will hurt on Diesel @Idle is the Turbo, kick it up to 1000 and your good..... let er run"

"Quote:

Originally Posted by MnTom

I guess I don't understand how you would be hurting the turbo at an idle. For lube the turbo is the first thing to see oil.

"Not enough oil at idle"

"Quote:

Originally Posted by MnTom

HUH? If there is not enough oil for the turbo at idle there surely won't be enough for the rest of the engine. I know on my 5.9 the oil pressure cold at the the filter head where the turbo get its supply from the oil pressure will go as high as 85PSI and warm it is about 60PSI. That is from a mechanical gauge I installed as a test.

The clearances between rod and crank, crank-journal are a lot less than a turbo, the turbo actually floats in the oil as it spins....."

You can read the whole thread here: http://www.irv2.com/forums/f123/idling-question-229301.html

 

Then there is a discussion about air filters (again, his posts are in bold):

"I use Donaldson filters, good price at Truck it parts a.com, K & N Air Filter ,a little more $$ but ya get what ya pay for."

I countered with this:

"You may want to read this: K&N Air Filter Review - Debunking the Myths (and why OEM is better)"

then.....

"

Quote:

Originally Posted by MnTom

You may want to read this: K&N Air Filter Review - Debunking the Myths (and why OEM is better)

Never had an issue with K&N even in my off road racing career, but, I have read several threads on here about OEM air filter causing diesel engines to fail as a result of allowing dirt in....., keep using the OEM ones."

Read that thread here: http://www.irv2.com/forums/f123/couple-questions-about-isl-370-a-229696-2.html

 

What I want is more info to counter his statements. Some of you are more "articulate" with a keyboard than I am. Help me show him the error of his thinking.

I actually googled the turbo thing and read several articles.  The only thing I found about prolonged idling is that after a hard run, you should shut it down within 5 min because the engine compartment temp starts rising and heating the turbo and engine back up, therefore removing the benefit of a cool down period.  I found nothing on the oil starvation crap.  

I actually googled the turbo thing and read several articles.  The only thing I found about prolonged idling is that after a hard run, you should shut it down within 5 min because the engine compartment temp starts rising and heating the turbo and engine back up, therefore removing the benefit of a cool down period.  I found nothing on the oil starvation crap.  

That is what I tried to explain to him, but he still says there is a lack of oil. The turbo is about the first thing to see oil whenever the engine is started.

I think cajflynn idles his truck all night and he still hit over a million.  I don't need any more proof than that.  

 Guber the 'tire changer', fresh from basic training at Mc Donalds, 

 

 

That^^^^^^is funny!!!!      

That^^^^^^is funny!!!!      

X2^^^^^^^^^^^^^

. Guber the 'tire changer', fresh from basic training at Mc Donalds, .   

Worst part is this^^ is probably true!

Even worse is see ASE certified mechanics that are lost working on a Cummins.

The problem with most of your filters is the difference between filters designed to be oiled, and filters designed to be dry. IIRC, most, if not all of K&N's filters are designed to be oiled. It boils down to physics. N a naturally aspirated engine, air flow is pulled past the air filter at low pressure, so oiling the element will trap the dirt particles within the filter, and they will stay there until then filter finally plugs up, because there's not enough suction to pull them through the filter element. When you add a turbo to the intake, the higher pressure suction is now taking those same oily dirt particles and because its a much higher suction pressure, it wil quickly (in comparison to the naturally aspirated engine) pull those dirt particles through the filter element. Because its oiled, then dirt particles don't have the opportunity to fall out of the filter, and are trapped against the filter element, meaning as soon as the element starts to wear out and spread, more particles are now bing pulled through the filter.

When my 3 daughters were in their late teens they knew lots more than me. Now they are all grown up and mature. I just smile and love 'em cause they're always calling me for advice and help with everything from buying a house to cars.

 

It's so cool to be so needed now a days

 

I think some of the best younger generation are the ones that have served in the armed forces.

We use oiled filters in my dirt bike.  I don't think a dry filter would stand a chance in the dusty conditions unless it was really dense and then you wouldn't have any flow through it.  One time I rode behind 3 guys on a dusty trail and I had cleaned and oiled the filter right before, when we got back it was caked because of all the dust they were kicking up.  

 

I think if you can keep up with it, oiled filters filter a lot better.  But it's a little hard to use on something with high HP as you'd have to build an enclosure for it.  I would never leave an oiled filter out like we do with the BHAF's because they get rain on and ruined.  Mine is always soaked after the rain.  

The difference is foam vs pleated. K&N uses a pleated material with a much more porous design that allows them to claim more air flow than any other design (material) on the market. This may be true but they have nowhere near the filtering capabilities of a foam filter. Not only that, but many dirt bike and ATV's run 2 stage filters much like off road engines that utilize a primary/secondary dry element. Two is better than one.

That being said, companies like Fleetgaurd and Donaldson have made significant improvements in dry element filtration. Protecting a turbocharged engine under sustained heavy engine loads flowing up to 1300 CFM at 99.8% efficiency in dusty environments like a field during planting season or a construction site is a testament to the technology of dry elements. Ive pulled the element out of the 5088 on my families farm and the exterior was packed with fine dirt sediment and yet the intake piping was clean as a whistle. I think if oiled filtration was superior we would see it in applications like this.

I was taught to keep the idle @ or slightly above 1000 in our tractors at an early age, and then it's for when you jumped out to pee, or open a gate. Not for letting her run while you ate dinner in the house.

We figured when you dropped below 1000, you can see this is where OP drops off considerably.. and hitting 1000 again brings the op up to normal.

But then, how many of us older lads in here remember the 'low idle' feature in semi trucks of the 70's? I sure do, those things when at the rest areas would be barely ticking over. 2-300 rpm?? This is when the driver was asleep in the sleeper, probably to keep warm or cool.

Now, since I was a kid in the 70's, maybe I was not aware of a cylinder shut down system. perhaps they were shutting down half the cylinders.. and it SOUNDED like they were running half the rpm. I dunno..

It'd been pretty easy with the ol pushrod type injectors, and the jake system..

As far as the KN.. they belong on 2 stroke engines! chainsaws, bikes, snowmobiles. most every diesel engine I own is double filtered, for safety sake! If the outer filter is damaged, I still have the inner..

As far as the KN.. they belong on 2 stroke engines! chainsaws, bikes, snowmobiles.

I wouldn't put one on any of my engines...oiled foam filter yes but no K&N for me. About the only thing I see them being good for is high performance engines used in competition where the engine is torn down frequently and maximum CFM is a priority over filtration. Going by the efficiency numbers they report themselves, I wouldn't run one on anything I cared about.

Agreed.

When I was a wild buck, and snowmobiled everywhere in the 70's, My old dependable Polaris Colt went everywhere on NO filters, in fact I don't remember any snowmachine in that era with a filter.. maybe an airbox for sound. Snow back 'then' was clean! LOL

"Snow was clean back then"

LOL, ya got me there. Your absolutely right, filtration isn't as important on a sled as other applications.

I wonder what they run on new machines these days?

The snowmobile and dirt bike vs Cummins is not a valid comparison. I'm sure oiled filters can be made and maintained to an adequate level of filtration for diesels, but it is not the best tool for the job.

The best filtration systems are a dry element with cyclonic system. It uses the air to flow around the filter to put the majority of solids on the outside where they fall to the bottom of the filter tube. There are rubber "drains" that the operator pops once in a while to empty them.

The snowmobile and dirt bike vs Cummins is not a valid comparison. I'm sure oiled filters can be made and maintained to an adequate level of filtration for diesels, but it is not the best tool for the job.

The best filtration systems are a dry element with cyclonic system. It uses the air to flow around the filter to put the majority of solids on the outside where they fall to the bottom of the filter tube. There are rubber "drains" that the operator pops once in a while to empty them.

Not really validating anything here, in fact was only demoting the KN to that level of use.

Your probably right on the best type of air filtration.. just about all my off road stuff uses that. Large metal can, and there is a inverted blades inside the canister that gets the air rotating as it enters the canister.. the heavies then (should) spin to the outside, and end up in that little 'sump'. The largest filter I have is 30 inches long, and 18 in diameter.. RBHF! costs 120 bucks, and then there is the 'small' one that goes INSIDE that one! We blow those outers out for about 2 years, and replace both inner and outer every 2 years.