premature turbocharger failures

Junkman · Dec 8, 2004

I am posting information that I received by e mail from Noria Corporation. If you would like to get onto their e mail list, follow this link. It is free and the information sometimes isn't relative to anything that I own, but many times it is educational and practical. One of this weeks tips is below.....

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From "The Practical Handbook of Machinery Lubrication"

A construction equipment contractor was experiencing premature turbocharger failures when certain engines were operated under full-load conditions and used around the clock. Investigation through oil analysis and diagnosis of the failed components revealed that the failures were caused by coking of the petroleum base oil within the turbocharger oil passages, thus restricting oil flow and resulting in bearing failure.

The initial cause of the oil coking condition was excessive temperatures within the turbocharger housing. A fully synthetic diesel engine oil was selected of the same viscosity as the original petroleum base mineral oil and installed. Premature turbocharger failures did not reoccur and oil temperatures dropped by about eight degrees Fahrenheit.

SkyPup · Dec 8, 2004

Anyone running a turbodiesel and NOT using a topline full synthetic like Amsoil or DelVac is asking for it. Dino oil will burn and coke for certain under load.

We've always used Amsoil 10W-40 full synthetic in all our turbodiesels over the last ten years and have never experienced a failure, even running full out for hours on end. /forums/images/graemlins/laugh.gif

slowrev · Dec 8, 2004

Junkman,
That is why I do not like turbo charged engines. Give me a larger natuarally aspirated one anytime over a smaller "pushed HP" turbo one. Turbos are often an manufacturers way to cut costs by using the same block in a larger tractor.

Ben

JerryG · Dec 8, 2004

The initial cause of the oil coking condition was excessive temperatures within the turbocharger housing. 
Coking is primarily done at shut down. The oil stops flowing at shut down and the extremely hot turbo actually cooks the oil to the bearing. This can be avoided by allowing the engine to idle for a short period before turning the engine off. This allows oil to cool the turbo bearing before shutdown. Synthetic oil does slow down the process because of it ability to withstand higher temperatures.

gsxr1100 · Dec 8, 2004

nothing new here. This has been an issue with dino oil for years in turbos.

This is why you are to idle the engine, which cooling turbo down. There are also idle kits that automate this process. Just turn the key off and walk away and the engine still runs till if reachs is shut off temp.

Welcome to the late 1990's.

SkyPup · Dec 8, 2004

Most turbodiesel turbocharger applications are NOT water cooled, although the exact same turbocharger setup when utilized on a gasoline engine IS water cooled due to the higher operational temperatures.

Plus, turbodiesel engine typically operate under sustained heavy loads for much longer periods of time than gasoline powered engine.

Shutting off any turbodiesel engine while it is running hard under load will coke the oil, however letting it idle down under no load for 15 seconds is all that is needed to prevent any coking from shutting down. You'd need to be drawing 1 atomsphere or greater intercooled compressor pressure to be heating up the turbocharger enough to worry about oil coking, and most turbodiesel turbocompressor application do not even put out 1 atomsphere and don't require the use of any intercooler.

Any OEM turbocharger will last as long as any other component of the turbodiesel engine if it is oiled properly and its air filtered properly.

Bird · Dec 8, 2004

( Premature turbocharger failures did not reoccur )

There is no such word as "reoccur". /forums/images/graemlins/wink.gif And I'll never forget that because many years ago, I got back a report I had written and had to do it over because I used that word. And that was before the days of word processors; everything had to be typed on a typewriter and NO corrections allowed. /forums/images/graemlins/frown.gif

DK35vince · Dec 8, 2004

( Any OEM turbocharger will last as long as any other component of the turbodiesel engine if it is oiled properly and its air filtered properly. )

I agree..
I've been around turbodiesel engines in trucks and many other types of equipment nearly every day for going on 20 years now.
It is extreamly rare to see a turbo failure.
I prefer the turbo diesel over the naturally asperated and would gladly have one in my tractor (to bad it wasn't an option /forums/images/graemlins/tongue.gif)

RalphVa · Dec 10, 2004

I believe it, Junkman.

Exxon chemical used to market an estor oil that they sold to aircraft engine folks. It was the only synthetic that Exxon had at the time that would stand up to turbine engine temperatures. I'm sure that Mobil 1 would work, too, as it will for turbocharged engines.

Ralph