You won't even need that... all you'll need is something to spoof the sensor(s) to make it think the cat is there.

More weight and complexity sure sounds fantastic to me.

Boom!!! American ingenuity within an hour!!!! And two years before the deadline...

OK, now read the California regs. 2008 for under 500 hp, and 2009 over 500 hp.

In California, ODBM is required, a marine version of ODB II. It's been a while since I have read the regs, but as I recall that requires monitoring catalytic converter efficiency, which means a sensor after the cat.

California's version of working with the manufacturers was building up a boat with cats, and running it in a few lakes. The test boat never touched salt water, yet they called the package good to go. When I asked them about this, the woman's response at the California Air Resources Board was, "salt water's not that corrosive". Brilliant.

I have yet to see accurate figures for justifying any emissions regulation. The figures are ALWAYS inflated by the government, sometimes by adsurd margins. Why? Because they can get away with it most of the time. People don't question them. When justifying the California marine regulations, they said there were thousands of gasoline engine powered boats running at any one time. Since we don't have any lakes in the LA basin, that meant all these boats had to be offshore. Yet, when I went by the coast everyday, most days there wasn't one boat out there. If there was one, it was usually a fishing boat with diesels. I did a little math, and by their figures there would have had to be a gasoline engine equipped boat lined up offshore EVERY 30 FEET!!! The entire thing was a complete lie.

Please people, when you look at emissions inventory figures, do a little math. I can guarantee you the numbers will be inflated every time. They just want something else to regulate.

Michael

Sorry to have opened a can of worms here but I just wanted to add some engineering viewpoints.

Michael, sorry, I was reading the EPA regs not the CARB ones.

You are quite correct that you require a sensor after the cat for diagnostics. However, you only diagnose part of the cat volume so there is normally a second larger substrate behind the second sensor.

Looked at all my automptive sensor specs last night and all of the mainstream stuff has to do 150-200hours salt spray even for cars. And that's at 5% saline which is Dead Sea levels of salinity. Last time I looked average seawater is about 3.5% isn't it? You do get salted roads and they do get wet and car engine bays are open to that enviroment.

Whether salty or not, water will kill a cat or an O2 sensor quite quickly (they run at high temps so water ingress will cuase cracking) so prevention would have to be the main approach. A water trap might have to be used to prevent the possiblity of reversion.

Colleague here was powertrain chief for the Gibbs Aquada (wierd boat/car thing) which had to pass car emissions AND pass USCG regs so it is doable. They had to create a reversion dam (a basic U bend would suffice!) to stop water ingress.

Why in a lab? Labs have nothing to do with it. See the INDMAR link earlier in the thread, they already have a marine cat implemented. It'll be implemented sooner than decades!

Boats are already running EFI on the latest engines so we're not talking about a major change. Yes the exhaust systems will have to be re-engineered and yes they will have to add oxygen sensors to the EFI but that's not as big a change as going from carbs to EFI in the first place. There are fuel system changes for evaporative emissions too but plastic tanks and fittings won't corrode either so that's also got to be seen as a plus point for owners.

It will put the costs up, of that there is no doubt, but I doubt it will be as much as you think when compared to buying a current EFI motor package.

Well I've tried to keep this to an engineering discussion not US politics. You're entitled to your own views on emissions but, as an Engineer, if I can keep something clean, improve fuel economy (at least compared with a carb running 12.5:1!) and maintain performance then that's what I'd want to develop.

2% of national emissions (your figure) is not a small number and a typical 90% reduction (the sort of cat efficiencies that are required) of noxious emissions would be significant once the technology becomes more widespread. Plus then there's the safety on board aspects that I also described, I'd have thought they'd be considered a good thing.

Unless there's an amendment somewhere that I missed, that says you all reserve the right to pollute as much as you want....

This is not meant as any offense to you as an engineer. The problem is that you as an engineer design this cat to work as you say efficiency, improve fuel economy, lessen pollution, and maintain performance. When the boat leaves the factory all of that is true, What happens 5 years down the road when the system you designed fails? Now the expense is on the boat owner. The problem with engineers is that they don't have to work on the POS system that they design. You wash your hands when it leaves the lab and go on to the next project. You as an engineer should be required to spend at least a year working on the equipment you design in the real world before it is ever released to the public. I bet you would then change your tune and realize that mechanical life expectancy out in the real world is way different and expensive than mechanical life expectancy in the lab. The cost and problems of everything today is passed on to the consumer. Instead of picking on responsible countries like the US, why don't you take your technology and figure out a way to stop the pollution in China and India, they need the help, not us.

As an Engineer, I agree with you. Like I said in my first post, it's often a decade or more before a newly-mandated piece of equipment is finally working as intended. Looks at what happened to light truck diesel OEM's (especially Navistar/Ford). A mandate comes out, forcing OEMs to adapt in little to no time putting to market untested equipment resulting in a plethora of failures.

What happens when your water pump fails? It's a regular occurrence for many shallow-water saltwater boaters. It usually takes a couple minutes to notice that youre temps have risen or an alarm goes off - youre engine gets hot and you shut it off. Usually, no big deal if caught in time. A water-cooled cat in the meantime is now probably at 500 to 600 or more degrees. Sounds really safe.

@Gerritm

India and China already have emissions standards that are at least as good as the US/EU had about 5 years ago. and they got there a whole lot quicker than we did!

China just introduced fuel econ regulations for new cars that are in excess of that in all the Western Economies.

Oh I agree with you about working with products in the market place. Large companies have warranty departments and, as a consultant, having worked on a few warranty analysis projects to feed analysis of real world customer experience back into the development cycle. SO no, I'm very aware of what happens when things get used by actual people.

Hey I'm not picking on the US and don't need to be told to go to China or India, they're your regs and you developed them all for yourselves. I was just talking about the engineering of such a solution and how it might be achieved. You don't know me chap, you shouldn't make assumptions about where and how I work. Labs? Sheesh! Let drop the "ad homs" and stick to engineering shall we?

@Cigdaze

With respect to cat overtemperature caused by a blocked water pump, that could be diagnosed too and shutdowns managed or power reduced. For example, every Japanese Domestic market car is produced with a cat temp sensor for that very reason. They are also right underneath the car and exposed to everything that is thrown at it. They are very reliable. So in the case of a failed raw water pump, the cat temp could be sensed and a diagnostic limp home mode eg limited power only implemented.

I agree about newly mandated stuff but we're not talking about reinventing the wheel here? A new exhaust system needs to be developed that marries automtotive catalyst technology ( a mature technology) with a water cooled enviroment with decent protection against water reversion and a damn good FMEA for the whole thing. As I said before, Marine EFI from carbs was probably a much bigger step than this.

Thanks for the dialog here.
Sounds like an awful lot of sensors and monitoring equipment.
So, what's all this going to cost the average boater? Weight?

You are taking a group of people that represent less than 2% of the vehicles in use and mandating them into regulations that make little sense as compared to the cost & benefits.The industry is already on the ropes with fuel prices. I did not implement the regs. some useless politician that probably has never had a real job or been in a high performance boat felt it was his duty to go after this group. I am not talking about working as a consultant on projects in a sterile enviroment. I am talking about working in the field under real world conditions. Getting your hands dirty. Realizing what it takes and costs to do the repairs. PAYING FOR THE REPAIRS. Every mechanic on this forum will tell you the same thing. Pollution is a very serious problem, I feel that the resources alloted to develope this could be better used for other more important pollution issues.

By the way if China and India are so far advanced with their pollution controls, why all of the concerns and pictures of the air quality before the Olympics. It has been on every news report in the nation. I know individuals that have been to major cities in both China and India and have described the unbelievable pollution present in the air and water. IMHO.

Who says China and India are anywhere near us or any European nation with regards to pollution control??? You can't find a dirtier region on this planet than China/India! They're disgusting.