Carbon Monoxide

This got me thinking. At what point would an engine die from sucking in CO and other exhaust products? I realize a newer vehicle with all it's oxygen sensors, etc would probably compensate for the oxygen deficient atmosphere. But what about an old motorcyle, tractor, or small engine?

I'm not really too keen on experimenting with this one. Thought I'd run it by the experts.

Thanks.

Concentration of CO in air Inhalation time and toxic developed 50 parts per million (ppm) Safety level as specified by the Health and Safety Executive 200 PPM Slight headache within 2-3 hours 400 PPM Frontal headache within 1-2 hours, becoming widespread in 3 hours 800 PPM , that's only .08% Dizziness, nausea, convulsions within 45 minutes, insensible in 2 hours

Put another way, What is "oxygen deficient" for an engine? If it's less than 16% for a human, what's deficient for an engine?

Thanks guys, for all the great answers. I've gleaned a lot of useful information off these boards over the last few years. They are really valuable!

About 20 years ago, my old boss left a propane forklift running in our shop all day long.He was trying to charge the batteries ! Anyway, I figured he was smart enough to open a door or something but he was not. I remember feeling woozy and sweating a lot as the level of CO2 grew , then I remember waking up in a chair in the parking lot and another employee shaking me and asking if I was OK .

I was lucky and wound up with only a bad headache.

I suppose the forklift would have eventually stopped on its own due to lack of oxygen but I don't think I will be a part of that experiment!

Ford Man

That would mean a gasser is 100% efficent burn! That is not possible with a carbon base fuel.

Take for example a combustion burner using a carbon vapor gas fuel supply. Even with the most efficent combustion process we still have CO as a by-product of combustion with a 98% burn ratio and thats with using a after burner process.

In a gasoline engine were using a liquid carbon based fuel that has more CO as a by-product of combustion as were having to change the liquid fuel into a saturated vapor fuel and that process is not 100%.

T_Bone

I've had a dose of CO once and I don't want another!!!!

Gerald J.

Pretty safe to assume that a "victim" would be long gone well before the engine would shut off.

On a 24ft x 24ft x 8ft sealed shop, it would take approx 9.2min for a typical gasser car engine to start using recirculated air intake.

With puter controled engines then the ECM will see a fuel enrichment and start in the defueling mode of the ECM program.

Without running a bunch more numbers, I would guess about 1hr for a typical 8cyl auto gasser engine at idle to fill a room with deadly CO.

With a single cylider engine, I would think about 4hrs as they don"t have a ECM program to start defueling the engine and the CO would increase at a faster rate.

T_Bone

On computer controlled outfits, they always start in open loop anyway. They don't drop into closed loop until the coolant reaches 151 degrees F.

Allan

1) Modern vehicles with O2 sensors have cat-cons and they don't make enough CO to hurt anybody.

2) In the days before cat-cons, a couple of love-struck teenage neighbors locked themselves in the garage with the engine running. They were dead long before the car ran out of gas which took about 8 hours. Had the garage been air-tight the engine may have died earlier due to lack of oxygen, hard to say. Interesting question.

Don't bet your life on that, because you will lose.

But, I'm betting against you. RIP, My condolences to the family.

***Disclaimer***
To all others out there: Don't try this at home!

"1) Modern vehicles with O2 sensors have cat-cons and they don"t make enough CO to hurt anybody."

I thought the cat-cons were to convert Nitrogen Oxides from the exhaust gasses to CO among others. Another lesser of 2 evils thing. Perhaps I"ve been misled?

Rockin" Farmer

Three-way catcons also remove NOx as well, converting them to N.

All catcons in current use are now three-way.

Mark

Mark