First of all, my XJ is bone stock 2WD so these questions are purely out of curiousity. Was thinking of buying a beater woods jeep, then thought about some of the deep water and mud i could run into in summer months, remembered some local jeep guys are running snorkels, and started wondering...what happens to a cooling fan when half the motor is submerged? If belt driven, does it bind from not being able to turn in the water? Does the belt slip? If electric fans do they short out? If mudding and radiator gets covered/caked, are there overheating issues?

 

Most people running snorkels are doing so for looks........I'd say 1 out of 100 snorkels every truly get used or are needed.

Yes, the belt can slip,
Yes, the fan can become a prop,
Yes, if electric, it can short out or burn up form the extra loading
Yes, if the radiator is covered in mud it will not cool like it should

Yes, the mech fan can bend and destroy the radiator,
Yes, the radiator can be pushed back into the fan,
Yes, it is rare to actually NEED a snorkel
Yes, if half the motor is under water, you have many other issues to worry about mud/water getting in as well (diff fluid, wheel bearings, transmission, tcase, distributor, alternator, A/C compressor, u-joints, brakes, interior electrical stuff, etc)

 

Snorkels do serve a purpose but I wouldn't want one because they can get damaged by tree limbs and vines, I think a cowl induction system is a better idea. Check out this video.

 

People who go through deep water will usually have their fans on a switch to turn them off if needed.

Otherwise you can try to waterproof them better.

 

Never said they didn't serve a purpose....just that the purpose they serve on 99 out of 100 jeeps is looks only.

 

If you don't water proof the electrical system it will cause bigger problems faster then a fan not turning.But you have a 2wd youll get stuck before you can damage your jeep probably.

 

I've run my 90 through water that was up to the bottom of the headlight/top of the bumper quite a few times. After hurricane Mathew, I ran through water up to the headlight for good 1/4 mile or so to get out of my neighborhood. Didn't hurt it a bit. No weird electrical issues popped up. Just keep in mind the air intake is about even with the headlight.

 

How bout the fuse box that is in the passenger side floor board? Water don’t affect that?

 

Well, I guess I need to modify my statement. I have gone through several crossings that the water comes up to the headlight when entering the water, but levels out at a lower point. When transiting for longer periods of time, the water is not higher than the bottom of the doors. I have not ran through water that was deep enough to come into the cab. I don't want to deal with moldy carpet, let alone wet electrical in the cab.

I am not promoting turning an XJ into a submarine. I'm saying I haven't done much in the way of waterproofing the engine bay and I have had zero issues. After I go wheeling, I pressure wash the engine bay and undercarriage to get the mud, sand, and seawater off of everything. Blast the electrical bits with a pressure washer, no troubles.

 

i have went into a hole where the water was midway up my dash before i got pulled back out. water level was over my hood up to the windshield.

i have a snorkel, only because for years i've been lucky to not hydrolock in these situations. so i put one on just incase i get in deep, i at least have a chance of a running motor to get me back home. electrical gremlins may take a bit of time to start acting up after it gets submerged, but i haven't run into any yet, and both fuse boxes have been under water for some time.

i still have my mechanical fan. i've only burned up one clutch fan so far. but i do want to install electric fans on a switch.

up here, there are always water holes and the level changes from day to day. sometimes with no by-passes.