Thread: Petrol Engines and Water

I wouldn't say I've done deep crossings at all yet. Probably the deepest has been around tyre depth (31/32").
My V8 has never missed a beat but I know of others that have drowned theirs on the same water crossing.

Even after pressure washing the engine bay, it has never failed to start.


Saying this, I bet it stops on tomorrows trip to the Watagans .

Do you have points or electronic?

Mine's electronic. Other electronics have stopped where mine's kept going though.

Normally points or electronic won't make a difference. Once the water gets inside the distributor, it doesn't take long to form condensation under the cap .

While on the topic, what's the best way to waterproof your V8 for deep water?

I read that a drink of water will do a lot less damage to a petrol engine than a diesel. True or False?

I think it was on the 4wdmonthly forum where a guy ruined his 3ltr Nissan engine while doing a water crossing (don't think he had a snorkel). Heaps of people chimed in saying they prefer petrol engines for water crossings. I was always under the impression that a diesel was ideal for those situations.

Originally Posted by rocky2509

I read that a drink of water will do a lot less damage to a petrol engine than a diesel. True or False?

Diesels have a much higher compression ratio than petrols.
Water doesn't compress like air does so there's a greater chance of bending a conrod or worse with water in a diesel motor.

You beat me to it. A petrol engine doesn't cope with water splash as well as a diesel, but IF the water does get down the inlet a petrol engine will probably just stop, whereas a diesel will probably suffer catastrophic damage.

Does getting the spark plugs wet affect them (like the sealing quality of the plug leads)? If I was to put some grease around the distrubuter cap, would that stop water getting in?

mmm water in a diesel will normal result in a con rod saying its had enough and get out and leaving the truck via the side of the block


In the Uk they run alot of Diesels becasue most events you are playing in mud. Where the diesel is best for it. as long as you have your snorkle conected properley. But then again you never know that for sure untill water gets in and buggers the engine