Don't forget the sand.............lots and lots of sand! I think there may be a few places where dirt has been imported in and there's even some clay but, it's still mostly sand.

 

How bout the fuse box and relays, are those water tight? I could imagine the ASD or fuel pump relay killing it if it gets wet.

 

yeah, during the dryer months, everything is nothing but sugar sand.
it actually gets real deep, its almost like mud for us lol

 

thank you, that didnt even cross my mind... that might be a pretty big pain in the *** to waterproof. but, its located relatively high, about level with the valve cover. im not looking to go any deeper than just above the headlamps, and only for short periods of time.

i have no idea how my '94 did it with very minimal waterproofing, battery & alternator in stock location, and a mechanical fan. factory freak, i guess.
or maybe the fact that it was obd1, made it less finicky.

 

 

Now I can't talk from experience because I try to avoid submarining my Jeep, lol, but I do know a bit about how engines have to function. I would highly doubt you're hydrolocking from the exhaust. In order for the water to get into the engine it has to flow up the entire exhaust system and displace all the air that's in the head and headers. Since an engine is designed to pump air in the intake and out the exhaust I would have a very hard time imagining how water would be able to displace the all that air unless all your valves are burned so bad they leak like a sieve, in which case you would have terrible performance.

I would agree with the people that said to check the intake, again. It's would be more likely that it's a slow leak that will allow water to seep into the engine over time like you mentioned. It gets enough water in to make it run poorly and stall, but it's not coming in fast enough to immediately hydrolock the engine. You let it sit and then try to crank it and it lets a nice big gulp of water into the cylinders and locks up.

I don't know if it's possible to start an engine under water at all, I would think the back pressure on the exhaust would be too much, but idk. Anyway, just remember the engine is a one-way pump and in order for it to hydrolock through the exhaust you're going to have to start pumping backwards, or allow the trapped air to escape.

Let us know what you find with the snorkel. A tip for checking the system would be to start at the lowest point with a garden hose and run water over all the connections of the snorkel/intake. Check the inside to see if its wet. Keep moving your way up to the top and see if you can find anything.

 

Ya..........I was stationed there for over 3 years. Try riding through that sand when it's dry on 2 wheels. You practically have to sit on the tail light to keep the front wheel from digging in.

 

when motors stall or are shut off some valves will be in the open position water can get in there since the heads lower than top of hood and waters over top of hood you get the picture

 

Yes, but that would require both intake and exhaust valve to be open. Even if the exhaust valve is open the cylinder would be air locked. As far as I know these engines aren't built such that both valves are open at TDC between exhaust and intake strokes.

 

motor stalls under water ,waters gonna displace the air..instead of page after page of my my vechicle dies when i completely submerge it under water just keep it at a safe level and all will be ok simple fix

 

Ever take a glass jar and hold it upside down and dunk it under water? Same concept. Can't displace the air if the air is trapped.

 

If the rear CCV hose or grommet were leaking, you could suck water right into the manifold and kill the motor. If the front CCV hose, valve cover, or oil pan gasket were leaking badly, it could suck in there too and end up in the oil, raise the level until the crank is beating the oil to a froth, etc. That Humvee in the vid has fording gear, it pressurizes the crankcase to a few PSI to prevent ingress of water. A few feet under water is 1-2 PSI of pressure. With the CCV, our crankcases are under a few inches of vacuum.

 

its gotten worse and more frequent; however now its stalling out in roughly ~30" of water. i havent been goin in water any deeper than my tires lately. i'll be in 4Lo, creeping along around 1300rpms, just easing it, and then it just cuts right out. go to restart it, it'll crank a few times, it's always trying to fire but wont get above 1,000 rpms and then stumbles back down and dies. when trying to restart it, once in a while it will fire right up and i can throttle up to about 4k rpms in nuetral, but within a seconds or two it cuts right out and falls back down & stalls.

it's only up 4" inches, but even if the water was at the top of the tires, the intake manifold, distributor, computer, coil, fuse/relay box, & the entire engine harness are all well out of the water, and im not splashing that hard. i can hit 2ft deep puddles at 25mph all day long, and believe me i do, but it just cant handle cruising in the water for extended periods of time.

i've popped my hood with the engine running and taken a hose & sprayer full blast to EVERYTHING under the hood, sprayed the fueltank & fuelpump area, dumped 5gallon buckets of water on my distributor & plug wires, snorkel, wiring harnesses, spent a good 30 minutes doing that. the engine didnt even stutter.

i understand the exhaust is fully underwater, but if it can crank, fire, and rev to 4k rpms for a couple seconds before cutting out, i dont see how that could be the problem.

help me out guys im lost

 

I had a similar problem and was the O2 sensor that is after the catalytic converter. After that the engine worked fine until I played in mud holes for a while. Coming back home the engine started to fail randomly. Depends the wheather. I bought new wires, sparks and distributor cap to replace the old ones. Also I will re-check again the O2 sensors. A mechanic told me that they need to be cleaned after wheeling in water and mud because can missread the exterior info and send incorrect information to the computer (loosely speaking).

 

OP, you might try hosing the crap out of the O2 sensor(s) and see what that does. Also check the exhaust around the sensors or upstream of them to see if there are any cracks that could be letting water into the exhaust system and affecting the sensor.