Hydrogen powered cars

[BigB]

There are many websites offering hydrogen producing systems for cars and vans etc. There are also sites debunking most of these. Non of the debunker sites mentions corrosion caused by the resulting water build up caused by burning hydrogen. Would burning hydrogen (as an additive and not the primary fuel) in an internal combustion engine cause enough water to build up in the exhaust system or even the engine to cause corrosion.?

[wildwood]

Engines blocks are usually casted from non-corrosive alloys.
Exhaust systems can be (and sometimes are) made from stainless steel.
Anyhow, I don't see how burning hydrogen would increase the likelihood of rusting.

Exhaust system mainly rust because on a parked car the steel is colder than the surrounding air - including the inside of the pipe - so it attracts any moisure in the air and rusts quicker then the body/chassis

[BigB]

I understand widlwoods answer however turbocharged engines could suffer if extra water was introduced and water internally in the exhaust would cause an increase in corrosion. Engine blocks do corrode quite easily when water is present. Have been out to plenty of vehicles that have sucked water into the cylinders and once the head is removed the cylinder is corroded quite badly. Even after a week this is apparent. The piston rings would clear this off in the swept area only though.
Im really just wondering if burning hydrogen in an engine would produce enough water to cause a problem or would it be carried out too quickly by the gases.

[nightmare]

You all appear to be forgetting that water is produced when petrol or diesel burn in an engine anyway, along with carbon oxides.
Have you never seen water dripping from an exhaust pipe on a cold morning ?

[Teddio]

For every kilogram of petrol or diesel burned in an internal combustion engine there is approximately one kilogram of water produced in the form of steam.
For every kilogram of hydrogen burned there would be 9 kilograms of steam produced.
Providing there are no cold spots in the exhaust system, the water would exit as steam or vapour. Of course for the first few minutes of running from cold, water would condense in the exhaust system; but it does this with a petrol or diesel engine anyway.