Catalytic Converters Off Road??

[DiscoSaffa]

Was chatting to a mate of mine over a bbq over the weekend and I made the comment that the D3 TDV6 was more desirable off road than my V6 petrol….. The reason I make that statement are things like range, better compression braking from the diesel (not that this is an issue any more with HDC) and better low down grunt……

But before I got a chance to say that, he said he agreed with me because of the issue of catalytic converters on petrol engines getting hot and starting bush fires. His company does a lot of work in the middle of nowhere and they run diesels purely for this reason…… Now first of all I thought that diesel engines also ran catalytic converters, but on this I am not sure…… Secondly, is this actually and issue? If so, is it an issue with the D3 or have the clever people at Land Rover done something to protect the environment from the cats?

The simple fix on my DII in South Africa was just to remove the cats …… 7 extra kW and such a lovely sound from the V8 when replaced with just a piece of pipe……..

[Graeme]

The cat on the 2.7 D3 is nicely tucked up out of harm's way.

If my remapped TD5 D2 is anything to go by, there can't be much heat being generated by its cat as the plastic invoice envelope on the replacement muffler is still intack after 30,000 kms.

[DiscoSaffa]

The cat on the 2.7 D3 is nicely tucked up out of harm's way.

So they do put cats on diesels..... I thought so...... it makes sense on a vehicle like the D3 that they would place them intelligently, so as not to be an issue……..

[JDNSW]

It is a serious problem although primarily on petrol vehicles. Every fire season there are fires started by catalytic converters, usually on the roadside where someone has stopped to take a phone call and driven off after a couple of minutes, leaving a fire smouldering behind them. The things ought to be banned outside the city!

John

[DiscoSaffa]

It is a serious problem although primarily on petrol vehicles. Every fire season there are fires started by catalytic converters, usually on the roadside where someone has stopped to take a phone call and driven off after a couple of minutes, leaving a fire smouldering behind them. The things ought to be banned outside the city!

John

So if diesels have them fitted, why is it primarily a problem with petrols?

Is the issue not that (in the example you quote) it is a problem with cars rather than 4x4s pulling off the road? They sit lower, there are more of them, and drivers tend not to be aware of such issues.......

As for banning, hardly a practical solution, would be far better to legislate how they are placed, and perhaps that they be better protected.

[Graeme]

There is a new situation where a diesel particulate filter (DPF) is fitted, as on the 1st batch of 3.0 D4s. The DPF gets burnt-out when it gets full of particulates and this is achieved by overfuelling the engine to cause the cat to reach the max possible temperature it can withstand in order to get enough heat into the DPF. I specifically ordered a 3.0 D4 without the DPF to avoid having to be concerned about setting fire to grass and crop stubble.

[JDNSW]

So if diesels have them fitted, why is it primarily a problem with petrols?

Is the issue not that (in the example you quote) it is a problem with cars rather than 4x4s pulling off the road? They sit lower, there are more of them, and drivers tend not to be aware of such issues.......

As for banning, hardly a practical solution, would be far better to legislate how they are placed, and perhaps that they be better protected.

Most diesels do not have them, some of the newer ones do, but they do not operate full time like petrol ones do, and I understand that when they do operate they do not reach such high skin temperatures.

Of course you are right, mainly cars are the offenders on roadsides, but 4x4s would be a larger risk overall because they are far more likely to be offroad, where the longer grass is likely to nullify the advantages of higher ground clearance.

Unfortunately better siting or protection is rarely easy, because the converter needs to be in the cooling airflow. And in cars at least there is little room to move it. In any case, virtually all cars and four wheel drives are designed primarily for markets where the climate is a lot wetter (and/or cooler), and it simply is not a problem.

John