Underbody wash / detail

ejay

TJ Addict
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Dec 29, 2019
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CA to WY refugee
So I've got some old mud under there. It's not really thick; mostly residue from not washing it off quick enough over the years. I don't want it to do any damage over time so I thought I'd find a way to easily wash it off. Maybe surface rust treat with rust buster, too. I want it to look puuuurdee before winter.

Anyone use a fallout remover with pretty good results?

BTW I've pressure washed and did a half-assed brush job but it did not do a great job. I'd love to get it on a lift and really blast everything but I'm without a lift.

I'm guessing some of you guys in the rust belt might have some pretty tried and true methods for washing the underbody.
 
I put on clothes I don't mind messing up and getting wet, take my creeper with me to the spray wash, and roll around and spray underneath with goggles on. I probably look like a weirdo, but it works.
 
I put on clothes I don't mind messing up and getting wet, take my creeper with me to the spray wash, and roll around and spray underneath with goggles on. I probably look like a weirdo, but it works.
Yeah, that's what I did last time. Some old coveralls, a pressure washer and a soapy brush. I didn't fair well. I was hoping on an acidic spray or something of that nature that would get in there deep.
 
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Yeah, that's what I did last time. Some old coveralls, a pressure washer and a soapy brush. I didn't fair well. I was hoping on an acidic spray or something of that nature that would get in there deep.
I wet it and spray it with simple green and let it sit for 20 mins, then head to the car wash. Works pretty good but you have to get the mud chunks out first. There is a professional detailer on this forum so maybe he'll chime in with some better tips.
 
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Pressure wash, simple green in a chemical sprayer, pressure wash let dry over night, WD-40 in chemical sprayer. The WD helps keep mud from sticking again and obviously displaces water as it’s designed to do.
 
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I just get under it at a self spray car wash like an idiot. Completely soak myself but I’m able to get it all out. We took a trip south of the salt lake a couple of years ago & got mud everywhere, took a few trips to get it all out. Since I started coating everything with fluid film twice per year it’s gotten much easier to keep it all clean.
 
I bought this attachment (and a longer section for the wand) to use with my pressure washer. I've used it on fresh stuff and it works pretty good. I've never tried on old hard packed mud though. I use it after every trip to the Outer Banks when I've been driving on the beach.

https://www.amazon.com/gp/product/B07K22DGRY/?tag=wranglerorg-20

1602048855515.png
 
I have also herd that people use a lawn sprinkler and let it run for awhile, I have never tried it but is sounds like it could work.
 
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I do the following after every wheeling trip:

- Pressure wash the bottom and top
- Spray the bottom, liberally, with Purple Power and let it soak for 10 minutes
- Pressure wash the bottom again
- Wash top with wash/wax
- Let it dry and grind/repair and paint any damaged steel areas
- Wipe down control arms, cables, etc. with WD40

At least 2X a year I also treat any rust and paint the bottom side with a Satin paint.

There is no doubt this is a pain, and some say excessive. However, I've been doing it for years now and the bottom of my LJ always looks like this

GBD9n64.jpg


Even after this
cKku4HG.jpg


If your Jeep is in rougher shape, you can still revive it. However, it's going to take some elbow grease and dis-assembly to make it happen right. Here's one I did with simple tools. I spent around $50 on Rust Reformer and Satin spray paint and did the entire frame and bottom of a TJ I bought. It took me a couple weekends to do though!

bKjWTej.jpg


tYcl13m.jpg
 
I do the following after every wheeling trip:

- Pressure wash the bottom and top
- Spray the bottom, liberally, with Purple Power and let it soak for 10 minutes
- Pressure wash the bottom again
- Wash top with wash/wax
- Let it dry and grind/repair and paint any damaged steel areas
- Wipe down control arms, cables, etc. with WD40

At least 2X a year I also treat any rust and paint the bottom side with a Satin paint.

There is no doubt this is a pain, and some say excessive. However, I've been doing it for years now and the bottom of my LJ always looks like this

View attachment 194719

Even after this
View attachment 194722

If your Jeep is in rougher shape, you can still revive it. However, it's going to take some elbow grease and dis-assembly to make it happen right. Here's one I did with simple tools. I spent around $50 on Rust Reformer and Satin spray paint and did the entire frame and bottom of a TJ I bought. It took me a couple weekends to do though!

View attachment 194720

View attachment 194721

That is some exceptional work. Hard work has paid off!
 
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I'm probably late to the party but, I need some ideas/direction:

My 2004 LJ had a bad oil leak when I bought it (back of valve cover and RMS). It had been leaking for some time. I bought it, fixed the leaks and really want to get the jeep back to looking like it never had a leak. It is not the wet oil but rather the old, dried oil/mud/grime mix that just wont come off. I've done well with the engine compartment and suspension components and have spent hours with simple green, pressure washer, rags, etc on the undercarriage but my hands just done fit everywhere. As you can imagine, its the underside of the motor, trans, etc. Its really driving me crazy as I am used to keeping vehicles pretty new looking.

Ideas?? I am thinking about paying someone to steam clean the undercarriage. Anyone do that before?


Thank you
 
I bought this attachment (and a longer section for the wand) to use with my pressure washer. I've used it on fresh stuff and it works pretty good. I've never tried on old hard packed mud though. I use it after every trip to the Outer Banks when I've been driving on the beach.

https://www.amazon.com/gp/product/B07K22DGRY/?tag=wranglerorg-20

View attachment 194708
I have the same one. Very easy to use and the mud just flows off the Jeep. Last time I had the Jeep really muddy I made sure to drive it in the rain. Then I used this pressure washer attachment and got tons more mud off.
 
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I'm probably late to the party but, I need some ideas/direction:

My 2004 LJ had a bad oil leak when I bought it (back of valve cover and RMS). It had been leaking for some time. I bought it, fixed the leaks and really want to get the jeep back to looking like it never had a leak. It is not the wet oil but rather the old, dried oil/mud/grime mix that just wont come off. I've done well with the engine compartment and suspension components and have spent hours with simple green, pressure washer, rags, etc on the undercarriage but my hands just done fit everywhere. As you can imagine, its the underside of the motor, trans, etc. Its really driving me crazy as I am used to keeping vehicles pretty new looking.

Ideas?? I am thinking about paying someone to steam clean the undercarriage. Anyone do that before?


Thank you
Id be interested in this as well. Ive sprayed purple power. Let it sit. And hit it with the spray wash. But it just seems like a pro job on a lift is whats needed. I have no idea where to look for such a service.
 
I do the following after every wheeling trip:

- Pressure wash the bottom and top
- Spray the bottom, liberally, with Purple Power and let it soak for 10 minutes
- Pressure wash the bottom again
- Wash top with wash/wax
- Let it dry and grind/repair and paint any damaged steel areas
- Wipe down control arms, cables, etc. with WD40

At least 2X a year I also treat any rust and paint the bottom side with a Satin paint.

There is no doubt this is a pain, and some say excessive. However, I've been doing it for years now and the bottom of my LJ always looks like this

View attachment 194719

Even after this
View attachment 194722

If your Jeep is in rougher shape, you can still revive it. However, it's going to take some elbow grease and dis-assembly to make it happen right. Here's one I did with simple tools. I spent around $50 on Rust Reformer and Satin spray paint and did the entire frame and bottom of a TJ I bought. It took me a couple weekends to do though!

View attachment 194720

View attachment 194721
Not trying to rain on your parade but it looks like you may have used too much elbow grease on that last picture--you polished the gas tank and exhaust right off!



Just kidding. Looks fantastic!
 
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Id be interested in this as well. Ive sprayed purple power. Let it sit. And hit it with the spray wash. But it just seems like a pro job on a lift is whats needed. I have no idea where to look for such a service.
I'm tm not picking on you but accumulate what's been commented in several posts..

I had experience in the chemical and cleaning industry...

Acidic cleaners are the wrong pH for dirt and are going to do nothing but possibly activate or worsen rust.

Purple Power as far as the cleaner itself is very high on the alkalinity scale because it has sodium hydroxide... This is also known as caustic soda. It's effective but if it's used enough it will eat off paint finishes and attack metals. purple Power sells a wash and wax product that is economical and one of the better washing wax products I've ever used for your exterior paint finish.

Simple Green is probably one of the best cleaners ever put on the market for repeated use...what will make simple green work the best is to put it on and give it 20 or 30 minutes to work.

Heat always makes a difference in the cleaning process...even a scrub brush dipped in hot water will clean far better than one in cold water.

A water hose hooked up to a hot water spigot is amazing.

Heat and agitation are your two biggest factors in cleaning... Pressure is a two-headed sword ... It can get bad things out of nooks and crannies and it can get good things out like Grease.

Also any cleaner needs to be rinsed thoroughly.. Some cleaners will attack bushings, gaskets and o-rings.

Also taking the vehicle for a good drive before you put it in a garage is a good idea if you want to keep ahead on the battle against corrosion.
 
I'm tm not picking on you but accumulate what's been commented in several posts..

I had experience in the chemical and cleaning industry...

Acidic cleaners are the wrong pH for dirt and are going to do nothing but possibly activate or worsen rust.

Purple Power as far as the cleaner itself is very high on the alkalinity scale because it has sodium hydroxide... This is also known as caustic soda. It's effective but if it's used enough it will eat off paint finishes and attack metals. purple Power sells a wash and wax product that is economical and one of the better washing wax products I've ever used for your exterior paint finish.

Simple Green is probably one of the best cleaners ever put on the market for repeated use...what will make simple green work the best is to put it on and give it 20 or 30 minutes to work.

Heat always makes a difference in the cleaning process...even a scrub brush dipped in hot water will clean far better than one in cold water.

A water hose hooked up to a hot water spigot is amazing.

Heat and agitation are your two biggest factors in cleaning... Pressure is a two-headed sword ... It can get bad things out of nooks and crannies and it can get good things out like Grease.

Also any cleaner needs to be rinsed thoroughly.. Some cleaners will attack bushings, gaskets and o-rings.

Also taking the vehicle for a good drive before you put it in a garage is a good idea if you want to keep ahead on the battle against corrosion.
No offense taken here. I'm well aware of the caustic nature of Purple Power. However, I've also used it for years with no ill effects. Part of the trick is to not use it on anything other than the bottom, only do so on wet surfaces, and never let it sit longer than 10 mins. Also, I routinely paint the bottom, so I haven't seen any issues there.

I have used Simple Green, but found that it didn't remove the heavy clay stains in my area as well. Admittedly, my experience with SG is dated and I'm open to giving it another shot!
 
No offense taken here. I'm well aware of the caustic nature of Purple Power. However, I've also used it for years with no ill effects. Part of the trick is to not use it on anything other than the bottom, only do so on wet surfaces, and never let it sit longer than 10 mins. Also, I routinely paint the bottom, so I haven't seen any issues there.

I have used Simple Green, but found that it didn't remove the heavy clay stains in my area as well. Admittedly, my experience with SG is dated and I'm open to giving it another shot!
Good post.. you are using Purple Power the right way and you really get down to a choice of acting fast with something aggressive or having to get something that isn't as aggressive more time.
 
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you really get down to a choice of acting fast with something aggressive or having to get something that isn't as aggressive more time.
This nailed it. I spend 6 - 8 hours wheeling, then two to three times that bringing the Jeep back to my happy state! :(