Forst st8

[Paddy1000111]

  On 10/06/2021 at 16:45, PeteB said:

I heard a story about a tow tug tractor where the driver kept on hitting the 'delay' for a regen. Eventually, the thing would not work and the dealer had to get involved and on the advice of the manufacturer, it had to to an enforced, long term regen cycle. It was sat in the yard at full chat for a day and a half to clear it out! The exhaust was glowing red and it used a massive amount of fuel too!

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I've done a forced regen before on a ford focus. The thing was so hot that it melted the tarmac underneath and had to slide a bit of sheet metal underneath. So bad for the car, not just being at 3500 rpm for an hour but the heat and the back pressure must have been unreal.

 

I can't remember what company it was now, Volvo maybe? They have cartridge dpf units in their hgv's that get exchanged at a service and they go off to a regeneration centre for a clean.

[Khriss]

Just a point here ( Paddy will know) you shouldnt just shut off a turbo engined deisel, if its been at full bore, a idle period to let cooler oil flow through the turbo, or the heat can cook the oil from latent heat in the castings. K

[Mike Hill]

  On 10/06/2021 at 18:23, Khriss said:

Just a point here ( Paddy will know) you shouldnt just shut off a turbo engined deisel, if its been at full bore, a idle period to let cooler oil flow through the turbo, or the heat can cook the oil from latent heat in the castings. K

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No.

 

You run down a turbo because when you shut off an engine the turbo fan is still spinning. Idling the engine for a while allows the fan to slowdown without running out of oil.This is especially important with turbos mounted higher up as the oil will actually drain away from the bushes.  There is precious little oil fed to most turbo compared to how fast they spin.

[Khriss]

  On 10/06/2021 at 18:38, Mike Hill said:

No.

 

You run down a turbo because when you shut off an engine the turbo fan is still spinning. Idling the engine for a while allows the fan to slowdown without running out of oil.This is especially important with turbos mounted higher up as the oil will actually drain away from the bushes.  There is precious little oil fed to most turbo compared to how fast they spin.

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Is wot i said really  🙄  but thanks. K 

Edited June 11, 2021 by Khriss

[openspaceman]

  On 10/06/2021 at 16:53, Paddy1000111 said:

I can't remember what company it was now, Volvo maybe? They have cartridge dpf units in their hgv's that get exchanged at a service and they go off to a regeneration centre for a clean.

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Sounds far more sensible.  Why can't you swap the exhaust on a a chipper and have it cleaned? After all it must be sensing a higher back pressure that  indicates a regeneration is needed.

[Paddy1000111]

  On 10/06/2021 at 20:30, openspaceman said:

Sounds far more sensible.  Why can't you swap the exhaust on a a chipper and have it cleaned? After all it must be sensing a higher back pressure that  indicates a regeneration is needed.

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Exactly, it goes off to be cleaned and you get a cleaned exchange unit. 👌

[Paddy1000111]

  On 10/06/2021 at 18:38, Mike Hill said:

No.

 

You run down a turbo because when you shut off an engine the turbo fan is still spinning. Idling the engine for a while allows the fan to slowdown without running out of oil.This is especially important with turbos mounted higher up as the oil will actually drain away from the bushes.  There is precious little oil fed to most turbo compared to how fast they spin.

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To be fair, it's both afaik. Turbos on a lot of higher power modern cars are water cooled as well as oil cooled but if you shut off the engine at max chat not just can it lead to cast warping but the oil burns into the bearings and creates a sludge. Turbos spool down relatively fast depending on size. 

 

Have a read of this: https://www.team-bhp.com/tech-stuff/idling-rule-turbo-charged-cars

 

but to summarise what it says: HKS - a top Japanese manufacturer of turbochargers - has this to say:"The number one cause of turbo failure is oil "coking". Oil "coking" occurs when a turbocharger is not properly cooled down and the oil that normally lubricates the center cartridge heats up and forms solidified oil deposits."That burnt oil eventually goes on to block passages.

[GA Groundcare]

  On 10/06/2021 at 16:53, Paddy1000111 said:

I've done a forced regen before on a ford focus. The thing was so hot that it melted the tarmac underneath and had to slide a bit of sheet metal underneath. So bad for the car, not just being at 3500 rpm for an hour but the heat and the back pressure must have been unreal.

 

I can't remember what company it was now, Volvo maybe? They have cartridge dpf units in their hgv's that get exchanged at a service and they go off to a regeneration centre for a clean.

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DPF regens on chippers certainly shouldn't ever be carried out near the working site with chip around!

 

Does make you wonder how much tier 5 engines are contributing to the "saving the planet" when regens are all factored into the mix and the subsequent fuel used over a tier 3a basic mechanical pump unit.

 

I know of a taxi that had an oil leak which when it performed a DPF regen it set the car on fire. It burnt to nothing in a bus stop and even melted said bus stop... The lad driving was a mechanic on road test in the customers car! My brother had the joy of making the phone call.

Edited June 11, 2021 by GA Groundcare

[GA Groundcare]

  On 10/06/2021 at 16:45, PeteB said:

I heard a story about a tow tug tractor where the driver kept on hitting the 'delay' for a regen. Eventually, the thing would not work and the dealer had to get involved and on the advice of the manufacturer, it had to to an enforced, long term regen cycle. It was sat in the yard at full chat for a day and a half to clear it out! The exhaust was glowing red and it used a massive amount of fuel too!

Expand  

We had a similar issue on a customers commercial mower (Yanmar engine) when we were in that game. Cost them over 3k in repairs for various high pressure fuel components, scv valve and resetting the ecu. The machine wouldn't allow itself to go over about 50% engine rpm. 

 

Certain components only have a number of cycles and have to be replaced in conjunction with others.

Edited June 11, 2021 by GA Groundcare

[dig-dug-dan]

I read on another forum of people jet washing out their exhausts to clear them out!