How to make a diesel engine quieter
- Thread starter fahafiz
- Start date
My tensioner prabably bounces 10 to 15mm each way, i watched all the pulleys and they run true by eye. Iv read a bit about the alternator pulley seizing, whats the main symptons....noise?
Regarding mixing oil with the derv, i used to have a rx8 and it was common to pre mix in the tank, but the rotary engines inject oil in to the combustion chamber to lubricate the apex seals...aparently the injection qty wasnt enough so pre mix would help.......rx8's eat cats if not driven properly, so its a bit of a bad comparasion.
Theres so much research out the for and against....each to their own, i imagine the best way is to run decat....again each to their own due to mixed reviews.
Regarding mixing oil with the derv, i used to have a rx8 and it was common to pre mix in the tank, but the rotary engines inject oil in to the combustion chamber to lubricate the apex seals...aparently the injection qty wasnt enough so pre mix would help.......rx8's eat cats if not driven properly, so its a bit of a bad comparasion.
Theres so much research out the for and against....each to their own, i imagine the best way is to run decat....again each to their own due to mixed reviews.
I thought mine was getting louder turns out to be a hole in the flexi exhaust and warn welding on the cat.
Have you got your engine cover and under engine splash thing on?
I have noticed a noise difference with oil used and petrol e.g. Shell special stuff made it slightly quieter
I will check my tensioner today and let you know how much it moves and if it gets quieter when held, could this also be down to warn engine mounts?
Have you got your engine cover and under engine splash thing on?
I have noticed a noise difference with oil used and petrol e.g. Shell special stuff made it slightly quieter
I will check my tensioner today and let you know how much it moves and if it gets quieter when held, could this also be down to warn engine mounts?
mk4 cupra wrote
Note that Brickyard thread is from 2009, and quotes American sources. American diesel was originally very high in sulphur content, so much so that European engines had to be modified for the American market. The reason was partly to do with the source of the fuel, American crude was far richer in these compounds. Americans had some very bad experiences as their diesel's sulphur content was lowered which is where the idea of pouring things into the tank gained new followers.
No. You are completely wrong on this, and it is fundamental to the point I'm trying to make.
Diesel vehicles have had to have two-way, oxidation, catalysts for many years now. These are slightly less complicated than the three-way catalysts mandated for petrol cars, but are still catalytic converters. They catalyse the conversion of hydrocarbons (unburned or part-burned fuel) to water and CO2, and carbon monoxide to CO2. They don't do anything to particulates (Particulate Matter, PM or soot).
They are most certainly not a soot cleaner.
More recent engines have to have a Diesel Particulate Filter (DPF) fitted as well as the cat. The DPF traps soot particles. It has to get rid of them every so often or it clogs and requires expensive replacement. DPF's get rid of the soot by "regeneration". At a suitable speed (motorway or A-road cruising), the ECU changes the fuel-air mix so that there is excess air in the exhaust, and the DPF burns the soot particles to CO2. It's this requirement to regenerate the DPF that is directly responsible for the appearance of lambda probes in diesel exhausts, where there were none before.
So your diesel car either has a catalytic converter, or a diesel particulate filter + a catalytic converter.
As I said above, it's a two-way catalyst not a three-way, but that has little to do with how it's constructed. A diesel catalyst will have a different mechanical construction for a number of reasons, including the fact that exhaust gas volumes on a turbo-diesel car will be much higher than those on a non-turbo petrol car.
It's good to test these things out for yourself rather than just follow the latest fashion. Your *smoke* may have been visibly lower. Your emissions (Phosphorus oxides, SO2, HC, CO) were higher, because the oil contains contaminants that have to be removed from diesel fuel, by law. Of course, these gases are invisible and the amount of them present in the exhaust gas is difficult to measure even with specialised and expensive equipment.
Two stroke oil is meant to be burned in petrol engines, which have a higher combustion temperature, so the oil will contribute a small amount of extra CO, HC and soot.
The majority of the soot particles in a diesel exhaust are microparticles and can't be seen as a black sooty cloud, only as a light haze in extreme cases. They are demonised as carcinogens by Californian environmental agencies who are following their own agendas.
The "typical smokey diesel exhaust" is the result of overfuelling. This can be completely eliminated, for a clean-looking exhaust, in modern cars with their fine injectors and computer control, but environmental paranoia mandates that we must also minimise NOx, Nitrogen Oxide production. This is what the EGR system does, and it makes smoke while it's in action.
Sorry I had to Join in with this convo I have put two stroke oil inp my Cupra tdi and I have made a thread about what I have noticed hear
http://www.seatcupra.net/forums/showthread.php?t=359004
And also hear is a link in how it works
http://www.brick-yard.co.uk/forum/adding-2-stroke-oil-to-diesel-tank-read-this_topic37935.html
http://www.seatcupra.net/forums/showthread.php?t=359004
And also hear is a link in how it works
http://www.brick-yard.co.uk/forum/adding-2-stroke-oil-to-diesel-tank-read-this_topic37935.html
Note that Brickyard thread is from 2009, and quotes American sources. American diesel was originally very high in sulphur content, so much so that European engines had to be modified for the American market. The reason was partly to do with the source of the fuel, American crude was far richer in these compounds. Americans had some very bad experiences as their diesel's sulphur content was lowered which is where the idea of pouring things into the tank gained new followers.
Muttly the fact of a cat on the diesel engine getting blocked or damaged due to using two stroke oil ain't really a worry due to the cat on diesel engines are not really what we should call a cat it's more a sut cleaner.
No. You are completely wrong on this, and it is fundamental to the point I'm trying to make.
Diesel vehicles have had to have two-way, oxidation, catalysts for many years now. These are slightly less complicated than the three-way catalysts mandated for petrol cars, but are still catalytic converters. They catalyse the conversion of hydrocarbons (unburned or part-burned fuel) to water and CO2, and carbon monoxide to CO2. They don't do anything to particulates (Particulate Matter, PM or soot).
They are most certainly not a soot cleaner.
More recent engines have to have a Diesel Particulate Filter (DPF) fitted as well as the cat. The DPF traps soot particles. It has to get rid of them every so often or it clogs and requires expensive replacement. DPF's get rid of the soot by "regeneration". At a suitable speed (motorway or A-road cruising), the ECU changes the fuel-air mix so that there is excess air in the exhaust, and the DPF burns the soot particles to CO2. It's this requirement to regenerate the DPF that is directly responsible for the appearance of lambda probes in diesel exhausts, where there were none before.
So your diesel car either has a catalytic converter, or a diesel particulate filter + a catalytic converter.
The cat on my tdi is a completely diffrent internal construction comperd to its petrol counter part.
As I said above, it's a two-way catalyst not a three-way, but that has little to do with how it's constructed. A diesel catalyst will have a different mechanical construction for a number of reasons, including the fact that exhaust gas volumes on a turbo-diesel car will be much higher than those on a non-turbo petrol car.
Myself from what I have read up and tests I hve carried out I have not found any reason it would or will damage my cat. I have smoke tested it with the 2 stroke oil mix and without the mix and with the two stroke oil mix my emissions where a lot lower.
It's good to test these things out for yourself rather than just follow the latest fashion. Your *smoke* may have been visibly lower. Your emissions (Phosphorus oxides, SO2, HC, CO) were higher, because the oil contains contaminants that have to be removed from diesel fuel, by law. Of course, these gases are invisible and the amount of them present in the exhaust gas is difficult to measure even with specialised and expensive equipment.
Two stroke oil is meant to be burned in petrol engines, which have a higher combustion temperature, so the oil will contribute a small amount of extra CO, HC and soot.
The majority of the soot particles in a diesel exhaust are microparticles and can't be seen as a black sooty cloud, only as a light haze in extreme cases. They are demonised as carcinogens by Californian environmental agencies who are following their own agendas.
The "typical smokey diesel exhaust" is the result of overfuelling. This can be completely eliminated, for a clean-looking exhaust, in modern cars with their fine injectors and computer control, but environmental paranoia mandates that we must also minimise NOx, Nitrogen Oxide production. This is what the EGR system does, and it makes smoke while it's in action.
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Seatmann wrote
American emission standards affect all of us, as manufacturers don't want to build different engines for the rest of the world compared to America, which is still the biggest market for motor vehicles by far.
The use of two-stroke engines in the US has collapsed to niche markets, such as garden equipment. If you mean that Americans pour two-stroke oil into their diesel without legal problems, that's because there is no emission testing for diesel engined cars in the US, the environmental legislation applies to manufacture.
The tiny amounts of two-stroke oil you are pouring into your fuel tank are nevertheless contaminating the fuel with the very compounds that have legally to be removed from that fuel to reduce emissions. The reason they have to be removed is because they poison the catalyst.
You challenged me on a simple technical question and I pointed you towards some documentary evidence of the facts.
I'm not going to stop you pouring anything into your tank. I just want to be sure you understand what it's doing to your car.
Muttley, the Americans have mad laws for emissions yet they use 2 stroke no problem at all, the amount we're talking about is far to tiny to cause any issues at all.
American emission standards affect all of us, as manufacturers don't want to build different engines for the rest of the world compared to America, which is still the biggest market for motor vehicles by far.
The use of two-stroke engines in the US has collapsed to niche markets, such as garden equipment. If you mean that Americans pour two-stroke oil into their diesel without legal problems, that's because there is no emission testing for diesel engined cars in the US, the environmental legislation applies to manufacture.
The tiny amounts of two-stroke oil you are pouring into your fuel tank are nevertheless contaminating the fuel with the very compounds that have legally to be removed from that fuel to reduce emissions. The reason they have to be removed is because they poison the catalyst.
You can see why I called you dad though? You come in all serious and ruin our fun lol 
You challenged me on a simple technical question and I pointed you towards some documentary evidence of the facts.
I'm not going to stop you pouring anything into your tank. I just want to be sure you understand what it's doing to your car.
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Muttley, give us a smile
As for the American market, they have crazy emission laws in a lot of their states, I read about it a lot on the tdi club but they still often use things like 2 stroke in their engines to help various factors.
Regarding sulphur they have less than us, their fuel is a bit pants compared to ours. The nozzles I bought from the states are designed for ultra low sulphur diesel.
The main thing is though that most of us don't need a cat and I don't have one.
On another note it's time to drill out my sender unit as I have a bad one with the stupid valve in it but that's another story.
As for the American market, they have crazy emission laws in a lot of their states, I read about it a lot on the tdi club but they still often use things like 2 stroke in their engines to help various factors.
Regarding sulphur they have less than us, their fuel is a bit pants compared to ours. The nozzles I bought from the states are designed for ultra low sulphur diesel.
The main thing is though that most of us don't need a cat and I don't have one.
On another note it's time to drill out my sender unit as I have a bad one with the stupid valve in it but that's another story.
Seatmann, since you ask so nicely, here's a smile
European fuel has always had less sulphur compounds in it due to the different feedstocks it is made from.
mk4 cupra wrote
Sulphur. Reduction of sulphur content in fuel allows different metals to be used to make better diesel catalysts, such as palladium, rather than the platinum catalysts that older diesels have to use. Palladium would be poisoned very quickly by sulphur compounds, wheras platinum is degraded more slowly. DPF's are more vulnerable to sulphur poisoning and will quickly be degraded. This is one reason why DPF's have only begun to appear recently.
The sulphur compounds in the oil are burned in the cylinder to produce oxides, mainly sulphur dioxide ( a colourless gas). There aren't any sulphur particles in the exhaust.
Right now, catalyst function on diesels is not checked at MOT, CO and HC emissions are not measured, so it's a bit difficult to tell what damage you're doing to the cat unless you have sophisticated exhaust gas analysis equipment and are prepared to use it regularly.
Should emissions testing be tightened up you stand a good chance of having to replace your cat if you've been using two-stroke oil for a while. Otherwise there are no ill effects - the catalyst matrix doesn't get clogged, it just stops catalysing.
European fuel has always had less sulphur compounds in it due to the different feedstocks it is made from.
mk4 cupra wrote
They ain't removed the sulpha in fuel due to damaging of the cat they removed it due to the cat can not remove the particles of the sulpha there for making the exhaust gas not as clean as it can be with out it
Sulphur. Reduction of sulphur content in fuel allows different metals to be used to make better diesel catalysts, such as palladium, rather than the platinum catalysts that older diesels have to use. Palladium would be poisoned very quickly by sulphur compounds, wheras platinum is degraded more slowly. DPF's are more vulnerable to sulphur poisoning and will quickly be degraded. This is one reason why DPF's have only begun to appear recently.
The sulphur compounds in the oil are burned in the cylinder to produce oxides, mainly sulphur dioxide ( a colourless gas). There aren't any sulphur particles in the exhaust.
Right now, catalyst function on diesels is not checked at MOT, CO and HC emissions are not measured, so it's a bit difficult to tell what damage you're doing to the cat unless you have sophisticated exhaust gas analysis equipment and are prepared to use it regularly.
Should emissions testing be tightened up you stand a good chance of having to replace your cat if you've been using two-stroke oil for a while. Otherwise there are no ill effects - the catalyst matrix doesn't get clogged, it just stops catalysing.
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