Has anyone ever washed the undercarriage?

[sugarwood]

Originally Posted by pavegeno

In the winter I wash it more often (after each drive) with underside hot water spray jets and steam to get rid of the salt.

Does anyone here do this?
Do you Just crouch down with a garden hose, and get what you can?
Do you jack up the car for more access?
Anything to look out for? Any danger spots where dirt, salt, debris tend to collect?

[steely]

I may rinse it once in a while - like I'd do for any of my cars, but I never take the p-car out in the salt. "Danger" areas would be the wheel wells mostly, and everywhere else if you drive it in the salt.

[BFT3.2]

Yes, the most very forward part of the rear wheel wells trap dirt and gravel, once moisture gets in there it's kind of trapped. On my "100%" rust free car I found some rust in there when I removed the rocker panel trim while redoing my rear suspension. It was fortunately on the thin sheet metal of the outer body(hidden by rocker trim) and not the tub or back of door jam. Since I have zero welding skills, I had the shop cut it out and replace, seal, paint it while I had some other work being done.

If it's packed with dirt/gravel, you really gotta get in there deep with a long flat head, air, vacuum etc. to get every last bit out.

But no, I don't drive it in the salt ever so don't really pay attention to cleaning the bottom. Maybe some Simple Green and rag the wheel wells once a year to remove all the brake dust.

[Cherry Bomb]

I put my car up on four jack stands, me on a creeper, one spray bottle full of water, another full 80/20% Simple Green/water mixed. Soak it down with SG/water mix. Let it sit a few minutes while you ask yourself, "why am I doing this"......then scrub with a vinyl hand brush, like one used for tire sidewall cleaning. Then, spray it down with water only, from that same bottle you keep refilling.

That's if you do not drive in all weather or offroad. For more severe filth, 1300psi power washer, not too close!

Your method and/or results may vary, this is what works for me.

[JQ911]

Not sure if it counts. I used to frequent those DIY carwash bays (once a week) even during winter coz i use it if there is no actual snow falling, and everytime I spend maybe a good 5 minutes blasting the wheel wells with pressure washer 1st spray with the foam soap then rinse using high pressure. I use the actual pressure of the washer on jet mode on the front wheel wells 7oclock to 4oclock motion and at the leftside back wheel well I am a bit easy on spray mode only on the 1oclock to 5oclock motion as the spray is directed to the engine. same on the right side rear wheel well at 7oclock to 10oclock motion. i also spray under the rear valance on spray mode only. Then lastly I just insert the jet spray under the carriage and blast away incliuding rocker panels since i dont have a lift. I remember have an issue once when I sprayed the rear wheels and valance on jet mode. i had a bit of burble when i started the car but that is just it. You will be glad you just did it when you move your car to dry clean it away from the bay and you see all those mud and salt laying around

[sugarwood]

Next time my rear wheels are off, I will inspect that kidney bowl area in the front of the rear wheel wells.

One day this Spring, I will remove all 4 wheels and do a simple green treatment of the wheel wells. Mine are mostly black.

[sugarwood]

Cherry,
Do you clean that huge center "waffle" undercarriage panel? Not sure what it's called.

[javadog]

That would be the floor pan...

Areas to clean include around the headlight buckets, around any oil or A/C lines, behind the door latch posts, above the tail light boxes, etc.

JR

[juanbenae]

I used at the close of every race season would jack up one side at a time, pull the wheels off and pressure wash the wheel wells, the underpan areas, underside of the tranny, motor, axles, brake and suspension assemblies. there was always tons of rubber & track scourge that was nice to get rid of before you were crawling around under the car doing offseason maintenance have junk fall in your eyes and mouth and face.....

[Reiver]

The only down side I can think of, on the torsion bar cars, is being careful (low pressure) around the front T bar adjusters. The 'seal' behind the adjuster 'hat' is a piece of foam and it's very easy for a high pressure stream to be forced past the seal. Once past the seal it would probably help retain the water.
My car has no rust, a Phoenix car for life, but when I rebuilt my A arms the only place I found rust was on the T bars themselves. I suspect a PO was power washing that area.
They were pitted so replaced them.

[Bob Kontak]

Originally Posted by javadog

Areas to clean include around the headlight buckets, around any oil or A/C lines, behind the door latch posts, above the tail light boxes, etc.

+1

Front wheel wells up top by where the antenna mast mounts. Crud can accumulate.

Basic cleaning - what Cherry Bomb says.

You can get your front wheel well inner fender (box) looking like the outside of the car.

You can steel wool the oil cooler lines behind the front wheel and they will look killer for two solid weeks.

[Bob Kontak]

Originally Posted by javadog

Areas to clean include around the headlight buckets, around any oil or A/C lines, behind the door latch posts, above the tail light boxes, etc.

+1

Front wheel wells up top by where the antenna mast mounts. Crud can accumulate.

Basic cleaning - what Cherry Bomb says.

You can get your front wheel well inner fender (box - the wall) looking like the outside of the car.

You can steel wool the oil cooler lines behind the front wheel and they will look killer for two solid weeks.

[Tippy]

Just be careful with Simple Green, it's corrosive if not fully washed off.

[Bob Kontak]

Originally Posted by Tippy

Just be careful with Simple Green, it's corrosive if not fully washed off.

+1

Simple Green, Fantastic, Formula 409, Purple Power, etc. can all do some chewing. Not "through" corrosion but it (they) can tarnish the finish.

Rinse and rub. You know the routine.

[sugarwood]

Originally Posted by Bob Kontak

You can get your front wheel well inner fender (box - the wall) looking like the outside of the car.

Yea, I've seen the pics here. I never knew it was color matched! I look forward to posting a before/after. But not for a while yet.

[steely]

Originally Posted by Bob Kontak

+1

Simple Green, Fantastic, Formula 409, Purple Power, etc. can all do some chewing. Not "through" corrosion but it (they) can tarnish the finish.

Rinse and rub. You know the routine.

I think the "orange" based cleaners are a bit caustic as well - proceed with caution.

Someone mentioned the pan - if you go this far, then yes, beneath(?) or above it, depending on your perspective - you might check there and the tunnel entry / exit points. If your rear shifter boot is torn, you'll literally be sucking dirt into the tunnel.

[Cherry Bomb]

Originally Posted by sugarwood

Cherry,
Do you clean that huge center "waffle" undercarriage panel? Not sure what it's called.

I sure do!

[BFT3.2]

Originally Posted by Tippy

Just be careful with Simple Green, it's corrosive if not fully washed off.

Embarrassed to say.. but I never knew that.

[Bill Douglas]

I do, but in a very Maori sort of a way. When it rains I take it for a long drive and all the puddles give it a (low pressure) pressure wash. I live at the beach so a LOT of salt air drifts under the car and settles on things.

[sugarwood]

Originally Posted by sugarwood

Next time my rear wheels are off, I will inspect that kidney bowl area in the front of the rear wheel wells.

I did one wheel today. I see what BFT meant about the kidney bowl area. I grabbed a pick tool to pry out a few pebbles, and then blew compressed air to get it all clean. Thanks for the tip!