Do you leave your diesel running ...?
I see many diesel drivers who leave the engine running while fueling (or other short-term occasions). For a while, I asked why they did that, just to see what their reason was. Never got the same answ...
Forum Discussion
dodge guy wrote:AH64ID wrote:
I rarely wait in line, so that's not an issue.... Spooling a turbo isn't what creates the shutdown requirement, it's heat. A turbo will slow down by the time you pull up, which is the only thing your spooling comment refers to, but that doesn't mean it's cool.
Yes, but a spooled up turbo is what causes heat. driving down the hwy under load the turbo is spooled up. by the time you coast down the off ramp and roll up to the pumps it has cooled down sufficiently to shut down.
High EGT's from high load (or low airflow) are what heat up the turbo, not just spinning. The compressor side heats up from spinning and it cools off right quick when the turbo slows down, but a slow turbo can still be too hot on the exhaust side from a heat soaked cylinder, cylinder head, exhaust manifold, turbine housing, and turbine wheel. On newer trucks with a cat in the downpipe the hot cat can push hot air back up to the turbo on shutdown as well.
It is very possible to be towing at lower rpms, low boost and high EGT's and get the turbo hotter than high rpms, high boost, and low EGT's. The turbo is not nearly as spooled at the low rpms and boost, but will require a much longer cool-down.
Simple monitoring will contradict your statement on coasting after towing.
DutchmenSport wrote:
So educate me please...I'm serious...what happens with the turbos if you do not allow cooling shut down first? Really, I want to know.
The oil in the turbo can cook, and then it cokes the bearing. That shortens the life of the turbo bearing.
