What kind of vehicle do you have and how much time do you plan to spend in the mud?
pre filter is good but if you plan on lots of water and speed I would build a shield if you are running an open air cleaner.
Seal up your distributor.
If you still have a engine driven fan you might want to shield the bottom of it. Lots of mud and water can suck the fan into the radiator. The list goes on just depends on what you going to do with it.
I would add that if you can, try to seal up the entire engine bay as much as you can. Some folks even hang some kind of deflector off the front end to keep mud from getting kicked up into the engine. Keeping chunks from going up into the belts will keep your alternator and power steering safe. I run an electric fan and turn it off during the run unless we are running back to back passes.
As Fordman and ChevyCrew said, keep your intake protected and seal your ignition from water. I have a shield built into the Dawgs' hood for the aircleaner and I seal the distributor cap with silicon.
Really depends on the rig and how much mud. You talking TTC Tank Trap holes or mud drags?
I'd seal up the distributer and wires. Alternator probably. Also intake for sure. Snorkel is cheap, engine isn't. Run the vents for the axles and gearboxes up high. Same for the gas tank.
My Jeep seems pretty watertight too though, I've had water come over the driver's door (window was down) as the Jeep was floating downstream. Still kept going... pretty freaky too. (pic is the only thing I have... not all that deep, but still pretty cool pic)
I want to know the tricks for getting a rig clean! Someone told me something about spraying Crisco all over the rig??
This was in Fairbanks. F-350 on 38s got pulled into the deep end by the current. It floated a good 40-50 feet and starting tipping over from the current. We pulled it out, and it ran for 30 secs after pulling the plugs... no water in the motor even... Some computer fried and insurance ended up totaling it.
You can see not even 30 feet from the truck, the water is just a few inches deep. We all drove down the stream a good ways... as long as you "guessed" where it wasn't deep, it was ok. I had no idea it got that deep until the Ford floating right passed me :shocked:
Worst part was he had a bin in the back with some guns, ammo, camping stuff, etc and it floated over the bed and was lost (currect is pretty quick). Almost lost his dog too.
Just making sure, but when you say seal it up, you mean dielectric grease? thats what I did. I know about the snorkle and sealed and drivetrain vents. Used to go to Knik glacier all the time and see how much silt we could get in the trucks. Alaska had to be the best place to go wheeling. Can't wait to go back.
Everything is pretty obvious when you start thinking about it. Going swimming in a river isn't the same as running in the mud unless you find a deep mud hole out someplace. If it's racing someplace like PV then it isn't that complicated. It ends up being what gets sprayed up into the engine bay. Then again you never know, anyone remember Weiser a few years ago? The only thing I worry about with the tranny (I run an auto) is that the mud used to get kicked up so hard it ripped my trannybrake wire off the connector.