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Bob Barry
02-03-2002, 03:34 PM
Had a fun day off-road with our club on Saturday; only one tweaked spring on my Cherokee (all the more reason to do up a flexier front pack out of the parts-leaves I have) and one stall in the water.

That is my question for the day, however; what is the best way to waterproof the engine on an FSJ?

Here's an example of an early, not-so-deep dip:

http://home.off-road.com/~wagoneer/cherokee/water_closeup_01.jpg

I have a water-line halfway up my hood from a later crossing, where I stalled out. I realize a snorkel is in my future, but for the electrical components (alternator, starter, starter relay), are there any ready-made fixes for keeping these things working when submerged or at least very wet?

When I go with the TFI coil, or any other electrical connector, I was going to rely on dielectric grease pumped in the front and rear of the connector, but I'm thinking maybe working up something more protective, like a slit of rubber tubing filled with grease (maybe even with a Zerk fitting to pump fresh grease into it).

Anybody know of any good waterproofing tips, or internet sites with such tips?

Oh, yeah, my bumper was redesignated as the "icebreaker", though as you can see from the following pic, it's more of an ice-catcher:

http://home.off-road.com/~wagoneer/cherokee/water_closeup_02.jpg

It's kind a hard to tell from the blowup, but those are chunks of ice blocking the grille. smile.gif

After the stallout on the later water-crossing, I was spraying everything electrical under the hood with WD-40 and picking ice-chunks out from the top of the distributor-cap (though, surprisingly, the inside of the cap remained clean and dry).

[ February 04, 2002: Message edited by: Bob Barry ]</p>

Bob Barry
02-03-2002, 06:09 PM
Just to add one more question: how effective are the little plastic vent-caps at the end of the breather-hoses on our FSJ's? Will they really keep water out of those housings?

Erix Jeep
02-03-2002, 06:18 PM
Bob, I can't see your pictures, but I can take a stab at your questions.

There is a product called liquid electrical tape that can help you seal all your electrical connections. Also, I have never put any faith in the OEM caps on the vent lines. They operate similar to PCV valves. When your warm axle hits colder water, it could keep them open. My preference is to get an inline fuel filter to clamp on the end, and raise them as high as possible. Just my .02 worth!

:D

PAJEEPER
02-04-2002, 12:26 AM
I would run all the vent tubes up into the cab. Those stock vents arent very good. I've found the place FSJ's really hate water at is the ignition. If you've ever seen the swamp jeep races on TV they run totally submerged sometimes. They totally encase the dist. in silicone and rubber and run a breather tube from the cap. And use a big snorkel too that should fix it up pretty good.

scotty
02-04-2002, 04:18 AM
the important thing is to use new ignition components.a worn out cap and rotor will have a hard time keeping the engine running when everything is good and wet. quality plugwires are the most important thing. if your wires cross fire and arc,it will not run under water.

other than that,i don not really do anything special.i use dialectric grease in both ends of the plugwires,and in the cap on both ends of the rotor. i used to seal my cap to the distributor with gresae,but have found this to not really be neccessary. sealing the cap with silicone is even more of a waste of time,cause it will actually help retain the moisture,rather than allowing it to escape,and when you do have to take the cap off its a PITA to scrape off the old silicone.

the little flapper vlaves work ok,if theyre actually working,wich they prolly arent after 15+ years. i made a second sorklel to attach all vents for the tranny,axles,etc. make sure tha the vent on your motorcraft carb is run to somewhere where water wont get in it. i have heard of people ingesting water into their engines thru the charcoal canister,so dont assume thats a good place to leave it.

since you have an auto,its even more important to protect it. water and autos dont mix.there should be alittle pipe or something that you can put a hose on and run up high. go to yuor local gm dealer and buy a late model locking dipstick.it should fit your tube,you will have to cut it to lenght and scribe the full/add lines.i got the shortest one they had and it was still waaaaay to long smile.gif it cost me all of 5 or 6 dollars.

another option is to use little filters on all of your breather vents. pep boys,and i think even the zone now sell a little tiny K&N type gauze filter that you can lube with K&N oil. i have been told that water cannot flow thru a properly oiled gauze filter.

keeping the intake air sealed with a snorkel is the next step. use a K&N filter in your air cleaner,and amke sure you plug up any sliitl places for water to seep in. i completely filled in the flapper valve on the bottom with silicone ,and reomved all the little fittings onthe sides of my stock air cleaner when i was still running it. you should be able to attach a stock air cleaner to PVC with a rubber 4" coupler,and a 4" to whatever size you want to run pvc reducer.i used to use clamps to keep the lid firmly attaced to the bottom.make sure that seal is in good shape,and lube it now and then with grease or vaseline.

last and not least,a mechanical fan is no good. if you want to play in deep water often,you need a clutch fan that will stop spinning,or an electric fan that you can turn off with a toggle switch. water has much more resistance that air,and it will put alot of strain on your engine to try and turn a mechanical fan(specially a big steel one-aluminum may flatten out) under water.

for the record,i have had my hood completley under water,and my engine still running. theres nothin funnerthan creek ridin on hot summer days :D

hope this helps. further questions? smile.gif

Bob Barry
02-04-2002, 05:30 AM
That's good advice, Scotty; I will immediately run all my breathers up to the engine compartment. I've got a clutch-fan with a stock metal blade; I've also got an old inner-tube that I was considering making into a belly shield from the front crossmember back to the swaybar, to keep out the splashing water (though the 6" thick ice would have ripped right through it this time; it will have to be pretty loose to "give" when it hits something hard.).