catylic converter with leaded petrol

Sometimes strange smell at the exhaust, sometimes you cant tell. There is so little lead in "leadded" fuel now anyway it should be OK. MOT station will tell you.

Probably not be able to tell, until MOT time if it needed the cat to pass the emissons test.

I've read that just a sniff of lead can knacker a cat - but can't confirm this!

The engine will still run fine. However its the lead in the fuel which coats both the o2 sensor and the cat matrix with lead oxide. This acts as a coating and stops the precious metals of the cat converting the noxious gases to co2 and does the same to the o2 sensor preventing its operation.

5 litres has probably not buggered it but will have taken alittle from its life.

Why did you ignore the "unleaded only" fuel sticker on the flap??

Tim..

I reckon the 5 litres bit might be the giveaway. You can't normally get leaded nozzles into the filler, so I reckon he's had a gallon can of petrol from somewhere and then found out it's leaded...

If it's LRP and therefore doesn't have lead in it, will the chemicals that replace the lead still damage the cat?

Mike

Well as a matter of fact, it was only 3.x liters. I just mentioned 5 to be safe. I don't live in the same country as you do and we CAN get leaded and unleaded petrol in any station over here, as a matter of fact it was only a few years back that leaded fuel was introduced to our country.

Anyway my car doesn't use an o2 sensor because it's a carburettor engine not EFI. So the only bad thing that happens if the cat spoils is that it polutes the air? We don't have to do emmission tests here so it should be ok right?

Thanks.

Yup!

A carb engine with a Cat !?!?

That's loonacy - you can never get a Carb engine to run completely stoich - surely that Cat wears out every year !

Yep and Yep.

Hello Nom.

24 Dec 03 09:00, you wrote to Brian Su:

N> A carb engine with a Cat !?!?

N> That's loonacy - you can never get a Carb engine to run completely stoich - N> surely that Cat wears out every year !

Nope, my mate's Golf 2 has a carb and a catalyst, 200+ k miles on the clock and the catalyst is alive and well. Judging by the cat's price (which is more than twice higher compared with the one fitted to a similar FI engine) it is designed to withstand not-stoich mixture.

Sergey

... Vegetarians eat vegetables - beware of humanitarians!

Nope. Almost certainly uses a "regulated carb" - like the Rover Metro does.

A chemically "correct" mixture. Not rich/lean Rich buggers catatonic diverters.

NO. If you have a cat, then you also have an o2 sensor. A cat only works effectively over a narrow mixture ratio scale, which the o2 sensor measures then passes to a controller.

With a carb'd engine and cat, you have a carb thats jetted on the rich side and an ecu controlled variable air leak, usually called a pulse valve which is plumbed into the inlet manifold after the carb. When the o2 sensor reports a rich mixture, the ecu opens the air valve and thus weakens the mixture. the o2 sensor then reports this and the reverse happens. simple see.

Tim..

Stoichemetric. 14.7:1 mixture ratio or "ideal" for combustion. Note that a cat equiped car on average runs slightly richer than stoich- 14.3 - 14.5:1.

Tim..