Any danger in shutting engine off at WOT?
 

I thought I remembered reading somewhere that shuting your engine down at WOT could cause reversion, hydro lock, or some other problem. Is there any truth to this? What are the odds?

I have done it in the past to see how the spark plugs looked. Did not have any problem and my daughter accidently pulled the kill switch on the passenger side once at damn near full throttle. No problem that time either.

Thoughts, opinions?

Not sure, as the seawater pump would stop turning to.

does the water pump in your car keep turning after you shut it off and go in the bar or store ?:eek:

Not following you.

I stated it stops turning, thus no incoming water.

If the motor kicks back any when it shuts down it can take a gulp

Water from your own wake can come up into the tailpipes and cylinders.

If you want to check plugs after a WOT pass don't turn off the key. Slow down to an idle, pull the shifter out of gear then pull the pulgs and read them. You will be able to see what you need to see like the heat line on the ground strap and center electrode and the color of the base ring of the plug. In cars at the end of the pass they are either clutched or basically put into neutral before the engine is shut off. It may or may not hurt anything, but the idea of turning the motor off at WOT isn't a good one.

The motor will keep turning over as the water flow over the prop is sufficient to keep the rotating assembly rotating until a lower speed, usually coming off plane. As a result all the water pumps will still be turning, the recirc pump and the raw water pump.

Now if it's a Bravo drive it can be a PITA to get it into neutral again as they don't like to shift unless running.

I would be concerned with the water coming back up the pipes caused by the force of the sudden stop. There would be no exhaust pressure in the pipes to force the water back out. I would think it would depend on the setup......how much of an uphill run does the water have to make, how far down stream does the water enter the pipes, etc.
Just because one boat doesn't have an issue, it doesn't mean another won't.
Eddie

I blew a fuel pump fuse at 95 mph (single engine vee) and motor stopped pretty damn sudden, didn't seem to hurt anything though but I wouldn't want to do it on purpose EVER, Smitty