cleaning the undercarriage

[Triple X]

Here's a question for you guys that like to get dirty on a regular basis. I want to pressure wash (not high pressure - just regular carwash spray wand pressure) the undercarriage. I've spent many hours lately lying on my garage floor under my VX and have taken note of the electrical connections/wiring harnesses that run along the undercarriage. However, I'm assuming that since the Vehicross is designed to ford shallow bodies of water that no precautions would be necessary before spraying the undercarriage. Can I get an Amen on that?

[Heraclid]

At the Ocala meet last year we had 7 VX's getting dirty in deep mudholes with standing water on top. PBR did not get in the mudholes but the rest of us did. Of those, 3 lost their A/C and then slowly everything else started to go. It was the alternators. Apparently the voltage regulators were not properly sealed, and since they are internal you have to get a new alternator. Dealers want $600 or so for them. This failure happened to VX1 (Scott), Frank, and myself. While Scott went through some holes multiple times, Frank and I were less gung-ho and still had the problem. Joe Black, Niv and Alex (-x-) were unaffected, and Alex went back for seconds and thirds and maybe fourths at some of the holes. So you may be fine and you may not if you get the alternator wet, but we had a significant ratio of alternator failures (3 out of the 6 VX's that went swimming). It is also mounted pretty low which doesn't make much sense for this type of vehicle. Just something to be mindful of. Definitely don't use a whole lot of pressure up under there.

P.S.- It happened to two 99's and a '00. I don't know if the 01's are safe from it, but we didn't have one fail. We had unaffected 99's too, though.

[Triple X]

Heraclid,
Thanks for the info. If I do give it a belly wash, I'll see if I can sheild the alternator and perhaps wrap the electrical connections to be on the safe side.

Thanks again.

[shawn]

i have a 99 and i go mudding alot so my undercarrigde is always in need of a good cleaning. i take it to the carwash and spray it down and i haven't had any problem. but after what HERACLID said about the alternator problem, i'm going to stay alway from it from now on.

[Simon Templar]

First of all let me say that my VX sees precious little off road activity. So, the dirt and grime that I clean off my belly is undoubtedly less severe than what a lot of you guys see.

That said, I at least try to clean the belly of my VX each time I wash (about once per week). While this won't get the really nasty stuff off, it will get the casual stuff loose. And it is simple.

I am lucky enough to have better than average water pressure at my house. I get out my high pressure lawn sprinkler (the spring loaded back and forth oscillating type)....run the hose under the front bumper down the middle to the rear and attach the sprinkler. (Actually....I lay it all out and then back the VX out of the garage over top of it.)

Turn on the water and let the sprinkler run. As I am getting everything else out to wash her down...every few minutes, I'll go to the front and pull another foot or two worth of hose toward me. By the time I am set up and ready to wash and wax....I've worked the sprayer head all the way to the front..and I am done.

No...I am not fooling myself into thinking everything is now spotless underneath. But I DO get a lot of minor mud and dirt run off....so I am doing at least SOME good. And with a street-bound VX....thats probably all I need.

And....I have yet to have troubles in terms of swamped electrical components.


....sT

[Baxman]

The following is an article I wrote for offroad.com, based on my experience with water in the '92 Trooper I traded for my VX.

Hydrolocked: a Lesson in Deep-Water Fording




Though sand typically drains quite well, the soil under the sand at Beverly Dunes Off Road Vehicle Park in central Washington is apparently less than permeable. The area is typically arid, however the week before our “dunes playday” it had rained heavily, causing water to pool up in some of the depressions among the dunes.

I drove through the edge of a large pool in my ’92 Trooper once; no problem. I drove through again, this time a little further from the edge. The water was about to the bottom of my door, though it seemed deeper from inside. Still, no problem. I thought this is cool, and it must look even cooler! I asked a buddy to station himself at the opposite end of the pool and I would drive toward him so he could click off a photo or two.

He was in position and ready. I proceeded. My earlier trips through had spawned some current action, causing a log to drift slowly across my path. I steered left to avoid it, which placed me just about in the center of the pool -- in uncharted territory. The Trooper’s nose dropped about a foot into a hole and all of a sudden the water was a whole lot closer. Instinctively and mistakenly, I hit the throttle. The sandy bottom offered excellent traction, and for the first time in my experience, the Trooper labored in 4-Lo against the resistance of the water. This created a “bow wave” that began lapping at the base of the windshield.

The engine died, but the Trooper had enough momentum to get the front wheels on dry land before rolling to a stop. I was congratulated by my buddies for making it ashore, and was assured by the photographer that the stunt had been captured on film. Relief and jubilation changed to horror as I attempted to crank the engine. A terrible sound emanated from under the hood like a starter engaged on an already running engine. I popped off the top of the air-filter box. The K & N was dripping wet.

We started pulling spark plugs, finding one cylinder completely filled, and a second partially filled. The engine was cranked, allowing the pistons to eject the water through the plug holes like a bulimic supermodel. Along with the water came impressive quantities of black carbon. When nothing but gasoline came out, we put her back together and she fired right up. In fact, during the 145-mile trip home, the Trooper seemed to have more power and had never run better!

Not long after, my speedometer would stop working intermittently – until my next attempt at deep-water fording that disabled the speed-sensor for good. This little jewel is located next to the transfer case and was eventually replaced, correcting the speedo problem. 60,000 miles later, I’ve had no other fording or hydrolock-related problems


Lessons Learned:


· Hydrolocking with an automatic transmission is not a serious matter because there is not a direct/mechanical link from the engine to the ground. With a manual gearbox, unless you can engage the clutch before the compression stroke of the hydrolocked cylinder, you will hear the sound of very expensive parts breaking because water is not compressible. The most likely noise you will hear is the sound of a connecting rod, freshly bent to 90 degrees, exploding through the side of the block.
· Without a snorkel, the absolute deepest fording depth is the height of the air intake, or roughly the top of the front wheel-well opening, about 34 inches in a stock Trooper. My door seals and transfer case lever boot held, but maybe I was just lucky.
· Carbon deposits in the combustion chambers are not fuel-soluble, and don’t necessarily get “blown out” after a long trip, but they are effectively removed by water. I’ve been told by veteran mechanics that pouring a quart of water down the carburetor at a high idle is an old remedy for carbon-choked engines.
· If you submerge driving lights, headlights, or taillights, it will be necessary to disassemble and dry them out within a couple of weeks. Water left in will not evaporate out and will cause rusting of reflective surfaces and eventually, rusting of the filament-support framework.
· Before attempting deep-water fording make sure diff and transfer case vent tubes are as long and high as possible, extending them if necessary. After fording, if the gear oil is milky or muddy-looking, drain and re-lube.
· In most off-road vehicles, the radiator fan is clutch-controlled so it will not turn when submerged. Note how it can be spun by hand when the engine is off.
· The Off-Roaders’ axiom “as slow as possible, as fast as necessary” is nowhere so true as when fording deep water. If you go too fast, the bow-wave phenomenon will get you!



Spraying your engine with fresh water will NOT be a problem.

[Heraclid]

Don't be overly worried. I wash my VX regularly and I spray the front good including the grill opening and the two openings in the cladding below it. I've also been underneath it spraying around with no ill effects. I have carefully sprayed inside the engine bay from the top. Without using a lot of pressure all of that should be fine.

Apparently some VXs will not have the problem anyway and it's just one of those hit or miss sort of things. At the meet we actually submerged the VX's up to about the headlights, and we hit the water with some momentum so the water came up through the cladding and so forth with some good force. It was kinda fun and great to see what you can get through in a VX, but it's not something I'd do again - the alternator concern being one reason, (luckily with an extended warranty that only ran me a $100 deductible and the dealer didn't say a word about all the grit and grime on the undercarriage) and the intensive clean-up being another. :-) After the meet I did find evidence that water spray had entered the air filter box but didn't get further than the bottom of that. And there is STILL some of that clay that washes out of places from time to time to this day (meet was last October). I'm guilty of it, but getting in deep water just isn't a real good idea.

[Triple X]

I was just looking through my manual trying to find the answer to the March/April quiz and found a reference to cleaning the underbody.

According to the Isuzu manual you CAN spray the underbody with water to remove dust, dirt, de-icing agents, salt, etc. They recommend that you do it at least once a year (in the spring) and state no precautions concerning any of the electrical connections located along the undercarriage.