Mostly stock XJ stalls while crossing big puddles. . .

[wavingpine11]

Hi all,

I've been wheeling my 92 XJ in central PA and there have been several occasions when I've crossed water a foot or so deep and the engine cuts right out, then won't start again right away. After as minute or so of sitting in the puddle, I can start it, and go on my way. If I crawl across the water--and what fun is that?--it doens't stall. I took it through some mucky mud this weekend and had no problems, but as soon as I was splashing the water around, it stalled. Any ideas on how to diagnose/eliminate this problem? The rig has a rebuilt engine that doesn't feel as strong as an original stock engnine and is stock height with 235/75R15 BFG AT's that love to rub when I go over bumps. I'll get around to getting it lifted eventually. . . But for now, just would like to cross water without having to shrug my shoulders at my girlfriend!

 

[8Mud]

A few obovious things come to mind. Plug and coil cables, distributor cap and air filter.
The boots on the plug an distributor cables and/or old cables will give you grief. I use the plug cable type with the long boots, preferably silicon type. They seal better and stay flexible longer, less chance of a crack or leak.
The distributor cap, usually has an air vent built in. First place the water seeps in. You can run a very mall beed of RTV around the sealing surface for the distributor cap, which also helps.
If you splash water into the intake for the filter box, it can saturate the paper elelment and stop the motor. In worst case scenarios the motor sucks the paper element into a cone or ball shape and tries to digest it through the TB intake or air box.
Sucking water in through the fresh air intake, through the filter, through the intake manifold and into the cylinders can be a motor killer. Anytime the water gets near the front bumper, you are in danger territory. Got to watch the bow wave. And learn to look in the filter before attempting to restart. When a piston tries to compress water, engine internals break.

 

[wavingpine11]

8mud--My guess was either electrical or water entry as well. I assumed that since the engine did start, that it hadn't gotten water in the cylinders, but you're right, I should have popped the air box open before trying to restart. That's a lot easier to do than push a dead XJ home. I'll check the distributor for the air hole and try to seal it and the sealing surface with silicone. Will this cause excess heat retention in the cap? Also, can I (should I. . .) test this hypothesis regarding the electrical side of things by popping the hood and spraying the wires and distributor cap while it's idling, or does that just sound stupid?