Leaving Diesel Run

As an Ex-engineer that did a lot of automotive, I say that you are well advised to let any turbocharged engine cool a little while before shutting it down. By let it cool, I mean let it run at something less than highway load for about a minute. That is all it takes for the system to get a lot of the heat out of the supercharger body.

Matt

In our situation, we will run longer once we stop because we have to have the engine running to put out the slides. Once the slides are out, we then level while the engine is running.

So, I would say we are running at 'high' idle for a good 10 minutes to get all the above done.

MM.

Matt_Colie wrote:
As an Ex-engineer that did a lot of automotive, I say that you are well advised to let any turbocharged engine cool a little while before shutting it down. By let it cool, I mean let it run at something less than highway load for about a minute. That is all it takes for the system to get a lot of the heat out of the supercharger body.

Matt

I'm also a former automotive engineer and agree. The time you let it run will depend on how hard you were working the engine and the ambient temperature. Normally 1-3 minutes is enough.

Turbos are powered by hot exhaust gas and the gasses can reach over 1000 degrees Fahrenheit. The turbo can actually get red hot under a heavy load. The turbo is cooled by engine oil circulating through the bearings and returning the oil to the oil cooler. If you immediately shut down the engine after a hard pull, the oil can't carry the heat away from the turbo and it cooks it. It will eventually lead to bearing damage and turbo failure.

For non-turbo charged engines, the oil and coolant will carry the heat away from the cylinder heads as long as the engine is running. Allowing the engine to run for a minute or two will allow the temperatures in the engine to equalize and reduce the possibility of a warped head or injector damage.

I am an old hick country ex-corn field farmer from Horse Creek Country in Illinois and I run my generator for a couple minutes without load as well before shutting down...

We non- engineer schooled country guys need air time as well haha...

Roy Ken

Matt_Colie wrote:
As an Ex-engineer that did a lot of automotive, I say that you are well advised to let any turbocharged engine cool a little while before shutting it down. By let it cool, I mean let it run at something less than highway load for about a minute. That is all it takes for the system to get a lot of the heat out of the supercharger body.

Matt

I think this is a good answer for most, now this is my thinking by the time one pulls of the highway and gets to a fuel station or campground this should be enough time for a cool down.
This goes along with what is in Mat's quote. JMHO

Read your owner's manual. It will specifically tell you EXACTLY how long to leave it running. Simple!

Ron

Simple answer to OP's question...he does NOT have a turbo, but thanks to all the engineers that responded relative to turbos....:h...anyway, new NON TURBO diesel engines do not need a cool down period.....Dennis

Interesting-- been a very long time since I have seen a normally aspirated diesel on the road. What do you have???

And as already answered, with a turbo diesel the answer is "IT DEPENDS".

If you just climbed a 5 mile 6% grade and pull over in a scenic overlook, yes 3-4 minutes would be proper.

But, if you got off the highway and drove at low speed to the CG and checked in, the instant you get to your site turn it off.

As with most things, a little common sense goes a long way.

Executive wrote:
Simple answer to OP's question...he does NOT have a turbo, but thanks to all the engineers that responded relative to turbos....:h...anyway, new NON TURBO diesel engines do not need a cool down period.....Dennis

How many NON turbo diesels are there out there..especially in the RV lineup. ( Thats what we are supposed to be discussing...RV's )

I like Wolfe10's answer best of all.