Protect Your Turbocharger

If your coach has a diesel engine, it almost certainly has a turbocharger.

Cummins VGT Variable Geometry Turbocharger
Cummins VGT Variable Geometry Turbocharger

And, if you ever have to replace the thing, it’s going to cost a lot of money.

You can greatly decrease your chances of ever needing a replacement by remembering just a few simple things.

When stopping after a hard run, never kill the engine without letting it cool for a few minutes first.

Never kill the engine while it is on “fast idle.”

Change your engine oil religiously.

Close adherence to those three rules will almost certainly assure you of a long turbocharger life, according to a Motorhomes of Texas news release by Mike Martinkus.

Now if you want to know the short version of “why,” read on.

Turbo’s are driven by the exhaust gas blowing out of the engine. That exhaust gas is piped to the turbo unit and causes an impeller inside the unit (think propeller) to spin and that impeller is mounted on a shaft that runs through the turbo housing to an impeller on the other side of the turbo body. That second impeller blows fresh compressed air into the engine and that compressed air gives the engine more power.

When the engine is at idle speed, around 600 rpm (revolutions per minute) the turbo impellers are spinning at several thousand rpm.

ISX15 for Heavy-Duty Truck (2013) produces 400-600 hp at 1450-2050 lb-ft
ISX15 for Heavy-Duty Truck (2013) produces 400-600 hp at 1450-2050 lb-ft

But, when the engine speeds up to just a thousand rpm (high idle), the impeller speeds increase to tens of thousands of rpm. When the engine is at highway speeds, the rpm of the turbo REALLY goes up—as much as 150,000 rpm. Yeah, that’s some spinning right there.

The turbo shaft spins so fast that it is very hard (read expensive) to manufacture bearings for a shaft that spins that fast so a lot of turbo’s shafts don’t have bearings but instead ride on oil. That oil is the engine oil which is supplied to the turbo under pressure by the running engine.

If the turbo does have bearings, those bearings are lubricated and cooled by the engine oil—that hot engine oil which is, in fact, much cooler than the turbo charger and its internal parts. It’s hot because remember it is driven by the exhaust—hot exhaust which gets hotter with increased rpm. The faster the engine runs, the hotter the exhaust, the hotter the engine oil becomes and the faster and hotter the turbocharger gets.

If you are driving hard, the engine is hot.

The turbo is spinning at 150,000 rpm and has reached 1,200 F. When you shut off the coolant supply (oil) by killing the engine, the oil that is in the turbo charger literally boils and cakes the shaft with burnt oil residue. That burnt residue does not make for a smooth spinning shaft and ultimately will cause the shaft to stall completely.

Bentsen Palm Village RV Resort Super Site
Let the turbo cool down for a couple of minutes before killing the engine. This diesel pusher is enjoying a Super Site at Bentsen Palm Village RV Resort south of Mission, Texas.

In addition to damaging the shaft the vanes that comprise the impellers are by necessity very light and very thin. Excessive heat and or lack of lubrication will eventually kill them. Those blades start flaking off and being ingested its bye bye turbo and maybe sayonara to the engine too.

Let the turbo cool down for a couple of minutes before killing the engine. Kill the engine from idle but give the turbo a chance to slow its spinning first.

Remember, keep the oil clean.

Worth Pondering…

“Get your motor runnin’
Head out on the highway
Lookin’ for adventure
And whatever comes our way
Yeah Darlin’ go make it happen
Take the world in a love embrace
Fire all of your guns at once
And explode into space.”

It could be the theme song of every RVer, though it’s not likely what Steppenwolf had in mind when they recorded Born to be Wild in 1968.

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Cummins Produces Two-millionth Diesel Engine for Ram Trucks

Cummins Inc. has produced its two-millionth diesel engine for Ram Trucks, highlighting the latest milestone in a storied partnership that spans four decades.

cumminsThe 350-horsepower, 6.7-liter, in-line 6-cylinder turbo diesel is distinguished by its “Cummins Red” rocker cover and breather.

But despite its 800 pound-foot peak torque rating, the historic engine—feted at a Cummins plant in Columbus, Indiana—will not see service. Instead, it will go on display, touring the U.S., according to a Chrysler Group news release.

“The Ram Truck-Cummins diesel partnership is one of the industry’s most enduring and certainly fitting of such a tribute,” says Fred Diaz, President and CEO – Ram Truck Brand and Chrysler de Mexico.

“Both companies have benefited greatly, but Ram diesel customers are the real beneficiaries. Every day they experience the toughness and capability a Cummins-powered Ram can deliver.”

Cummins began supplying engines to Chrysler Group in 1988. Today in North America, only Ram-brand pickups and chassis cabs feature the coveted Cummins “C” logo.

“I am immensely proud of our association with Cummins,” says Bob Lee, Chrysler Group Vice President and Head of Engine and Electrified Propulsion Engineering.

“And I have no qualms matching our truck diesels against those of any competitor for performance and durability.”

For 2013, Cummins-powered Rams boast capabilities and features include:

  • Best-in-class torque and a 10 percent fuel-economy improvement
  • Exclusive dual-inlet “Ram Active Air” that adjusts induction according to driving conditions for optimal performance
  • “Smart” exhaust brake for smoother driving characteristics
  • Best-in-class 15,000-mile oil-change interval
  • A new cooling system for improved performance and durability
  • B20 fuel capability
  • Next-generation Selective Catalytic Reduction (SCR) and diesel exhaust fluid system with range of up to 4,000 miles between refills
  • Dual fuel filtration system for enhanced reliability and durability in virtually every climate and environment
  • Unsurpassed powertrain warranty – five years/100,000 miles

Cummins-Diesel-Built-for-RamThe Chrysler Group-Cummins partnership traces its beginnings to 1985, when development work began on a 5.9-liter 12-valve in-line 6-cylinder turbo diesel. When it launched in 1989, it was rated at 160 horsepower and 400 pound-foot of peak torque—less than half the numbers for today’s High-Output 6.7-liter Cummins turbo diesel.

In the 2013 Ram Heavy Duty pickups, the top-line Cummins engine makes 385 horsepower and a best-in-class 850 pound-foot of torque.

Other notable events in the evolution of Cummins diesels produced for Chrysler Group include:

  • 24-valve design introduced in model-year 1998.5
  • Adoption of high-pressure common-rail fuel delivery in 2003
  • Named to Ward’s 10 Best Engines list in 2004
  • Displacement increased to 6.7 liters from 5.9 liters in model-year 2007.5
  • Met 2010 EPA emissions certification in 2007

Details

Ram Truck
dodge_logo
The Ram Truck brand continues to establish its own identity and clearly define its customer since its launch as a standalone vehicle brand.

The Ram Truck brand has the most innovative lineup of full-size trucks on the market. Ram Truck has emerged as a full-size truck leader by investing substantially in new products, infusing them with great looks, refined interiors, durable engines, and features that further enhance their capabilities.

Chrysler Group LLC
Chrysler Group LLC, formed in 2009 to establish a global strategic alliance with Fiat S.p.A., produces Chrysler, Jeep, Dodge, Ram, Mopar, SRT, and Fiat vehicles and products. With the resources, technology, and worldwide distribution network required to compete on a global scale, the alliance builds on Chrysler Group’s culture of innovation, first established by Walter P. Chrysler in 1925, and Fiat’s complementary technology that dates back to its founding in 1899.

Headquartered in Auburn Hills, Michigan, Chrysler Group’s product lineup features some of the world’s most recognizable vehicles, including the Chrysler 300 and Town & Country, Jeep Wrangler, all-new Dodge Dart, Ram 1500, Jeep Grand Cherokee SRT8, and Fiat 500.

Worth Pondering…
I think and think for months and years. Ninety-nine times, the conclusion is false. The hundredth time I am right.

—Albert Einstein

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