submerged tailpipe

[cfo20]

I took out the waverunner today and yesterday, but the lake is severly at a high water level, so most of the boat ramps are totally submerged. Anyway, when I back my X into the water, the tailpipe becomes submerged and the engine starts to run rough until I take it out of the water. It is only in for about 20 seconds at a time. My question is, will this cause any immediate or long term damage to the engine, computer or anything?

 

[JDraper]

Since your engine kept running while the exhaust was under water, that will cause no damage whatsoever. The reason it runs rough is because the water is drastically increasing the backpressure in the exhaust, which bogs the motor down.

If you stall it or shut it off while the engine is under water, you can cause some damage. You could damage the cat converter or 02 sensors, or if it is deep enough, have some water get back into the motor (You would be floating in the seat at that point).

 

[cfo20]

tailpipe

Thanks for the info. The water level doesn't go any higher than mid-level on the rear bumper, and I am hoping that it won't rain anymore for a while which would bring the water level down to where it should be. Since it is somewhat inclined as well, I don't think the water would make it that far into the pipe, maybe only a foot or so, but not far enough to the o2 sensors. But I appreciate the warning, I have heard to many horror stories about "I thought I could make it through that puddle." I also thank you for mentioning the o2 sensors, it is about time for those to be replaced as well.

 

[james t]

this must be just a freak incident, or perhaps the moon was aligned just right, but i have an experience with this. when i was around 13-14, my father and i were out muddin'. 76 F100, 390, headers, no cats, 36" Swampers, etc. we got stuck in a VERY deep mud hole, and while we were assessing the situation the truck died. (combo of reduced back pressure and vapor lock, the motor got very hot due to MANY high rpm blasts and a undersized radiator.) anyway, as it sat there, unknowing to us, both exhausts created a vacuum and sucked water into the engine. all the way through the exhaust, mufflers, headers, right into the cylinders. well, you can guess what happened when he jumped back in and turned the motor over. verdict, 3 bent connecting rods. good 'ole hydrolock. since then, i have never heard of this happening to anyone i know. must have been fate. d@mn, i miss that truck...

 

[Dannyboy]

one last thing to consider here, your tranny-tcase and rear diff all have breather tubes. when they are hot and cool water is present, it will suck in the cool water into the hot diff, tranny etc like a vacuum. You can relocate these tubes real easy for about $5 in hoses and that way you will keep the elements out.

 

[yob_yeknom]

Originally posted by james t
this must be just a freak incident,

Because it died buried in mud. The exhaust system was hot and the gases in it also. The cold mud cooled all that off and made the gases compress, creating a vacuum. With the system being underwater/mud anyways, it ran into the system and the vacuum sucked it up even farther. If only the back of the system was under and the water wasn't able to run into it, it wouldn't have happened.