Thread: Turbo Diesel, gentle cooling down or glazed bores ?

The only good reason to idle down a turbo diesel is to protect the turbo bearing from damage from heat soak burning the oil. To that end an EGT of around 150°C is a good a shut down point as any IMHO.

Originally Posted by bee utey

The only good reason to idle down a turbo diesel is to protect the turbo bearing from damage from heat soak burning the oil. To that end an EGT of around 150°C is a good a shut down point as any IMHO.

This.

The worst thing you can do to any diesel is prolonged idling.
One ex fleet owner (engines were DD60 Series) I knew would check his drivers data and anything over 2.5 minutes idling earned a warning, found a couple of tines and he'd sack them.

As above. The only reason to "cool down" is to allow the turbo to cool down and slow down. But this is only necessary if the driving pattern right before stopping has involved high power operation. The reality is that in most cases the cooling down has already been done as the vehicle slowed - even if it has just been driving at high speed on the freeway, most of the cooling down necessary would have happened as the vehicle slowed. About the only time any special cooling period would be necessary is the sort of scenario where you have been towing up a hill and stop at the top at a lookout.

In any case, the maximum idling time needed would be no more than a minute or so. If the manufacturers thought it was necessary they would fit a switch off delay, or at least emphasise the need to delay shutting down. Never seen that in an owner's manual, but I have seen advice not to idle for prolonged periods.

Susceptibility of diesels to cylinder wall glazing is going to be dependent on the particular model engine - some are known to be particularly prone to it. I expect it will depend mainly on the piston ring configuration and lubrication.

Once a upon a time Turbo timers were avail aftermarket, it they were really bn nneded the nmanufacturers would have fitted them. The Mitsu Starion of yesteryear had a turbo timer didn't it?

In South Australia it is against the law to leave a vehicle with the motor running. The Wallopers have been known to tour the car yards defecting any vehicle with a turbo timer for they 'could' be left flouting the LAW.

Mike

Its not a technical reply but a solution to your problem. New lodgings for number 3 son. 😆

Originally Posted by bee utey

The only good reason to idle down a turbo diesel is to protect the turbo bearing from damage from heat soak burning the oil. To that end an EGT of around 150°C is a good a shut down point as any IMHO.

Agree, - and I could think of other, equally expen$ive and less useful additions to his Toy...

Even a larger oil cooler..... to match his larger aftermarket (turbo) charge - air Cooler.

Originally Posted by Roverlord off road spares

Once a upon a time Turbo timers were avail aftermarket, it they were really bn nneded the nmanufacturers would have fitted them. The Mitsu Starion of yesteryear had a turbo timer didn't it?

They are needed for people that dont idle down their turbo
Manufacturers dont fit them because (Bean counters) also it should state in your owners book not to shut down the engine straight away after working the engine hard Maybe in fine print but im sure as hell they would cover their arse