Rust in rear wheel well

[Jayc4929]

I bought this 2013 jeep wrangler jk sport 2 door about 5 month ago and im still making payments on ut. I do have a warranty but i am pretry sure it doesn't cover this issue. I just found In rear driver side wheel well that it is basically crumbling away fairly easily in the area the arrows are pointing to. My questions are, how can I repair this and is it structural? Structural meaning is it part of frame. What part is this if i was to describe it to someone? Im not a welder and would probably have to find someone to do this for me. Im concerned it will get worse and spread to more areas. It's pretty close to that filler tube and vent and I'm not sure how comfortable most people are with working in that area. Any advice is appreciated

 

[JeepJeezy]

Ouch. I see you're from NY. I'm betting my paychecks money that's not your only spot in really bad shape. As far as repairs, are you looking to repair yourself or have a shop make the repairs?

 

[Jayc4929]

Ouch. I see you're from NY. I'm betting my paychecks money that's not your only spot in really bad shape. As far as repairs, are you looking to repair yourself or have a shop make the repairs?

Well I'm definitely not a welder so I'm probably looking at finding someone to do it. Yes om in NY and there was rust on undercarriage when I bought it. All appeared to be surface rust. They undercoated it before I bought from used car dealer, but they didn't remove loose rust beforehand. I THOUGHT I checked everywhere for more severe rust but apparently I missed this section. Been underneath with a screwdriver tapping on everything i can find to test for more areas. Which i did the same before i bought it. I've owned it now for 5 months and still making payments also. VERY aggravated with myself at this point for not finding this right away.

 

[pc1p]

I'm afraid that @JeepJeezy is likely right - this probably isn't the only spot you're having issues with. I would check the torque boxes directly under the rocker panels, plus hidden areas such as the formed, sheet-metal "braces" that traverse the body from driver-side to passenger side.

If it turns out that these areas are the only problem areas, then the work ahead of you has a couple of options. You could obviously cut and weld in new panels. This would obviously be extensive and likely expensive and time consuming. An alternative option would be to knock off any loose rust and then use an encapsulator to stop the cancer from spreading. This could be followed up with some structural expanding foam (don't laugh, the JK has some of this from the factory!), followed by some additional encapsulator or sealer to keep the material from soaking up water and salt.

 

[Jayc4929]

I'm afraid that @JeepJeezy is likely right - this probably isn't the only spot you're having issues with. I would check the torque boxes directly under the rocker panels, plus hidden areas such as the formed, sheet-metal "braces" that traverse the body from driver-side to passenger side.

If it turns out that these areas are the only problem areas, then the work ahead of you has a couple of options. You could obviously cut and weld in new panels. This would obviously be extensive and likely expensive and time consuming. An alternative option would be to knock off any loose rust and then use an encapsulator to stop the cancer from spreading. This could be followed up with some structural expanding foam (don't laugh, the JK has some of this from the factory!), followed by some additional encapsulator or sealer to keep the material from soaking up water and salt.

Thank you for the advice. I have knocked on the frame with a screw driver and I have not noticed any other areas even remotely like this section. Although I believe you may be right as well seeing that I missed this section until now. There was significant rush on undercarriage when I bought this from used car dealer 5 months ago. Although majority was surface rust so they sprayed undercarriage before I took possession. What they didn't do is clean off loose rust before spraying.
By encapsulater what type do you think would be best? And if I were to go with second option. Do you mean spray foam? If so, how would I keep it in place as it dries? There is going to be a pretty decent sized gap once I remove most of the brittle rust.

 

[pc1p]

Thank you for the advice. I have knocked on the frame with a screw driver and I have not noticed any other areas even remotely like this section. Although I believe you may be right as well seeing that I missed this section until now. There was significant rush on undercarriage when I bought this from used car dealer 5 months ago. Although majority was surface rust so they sprayed undercarriage before I took possession. What they didn't do is clean off loose rust before spraying.
By encapsulater what type do you think would be best? And if I were to go with second option. Do you mean spray foam? If so, how would I keep it in place as it dries? There is going to be a pretty decent sized gap once I remove most of the brittle rust.

For an encapsulator, paint, and similar stuff, I like Eastwood products. I'm currently working on my JKU and am cleaning and sealing BEFORE it becomes an issue (https://wranglerjkforum.net/threads/2008-jku-argenta-build-thread.32367/post-471207). I'm hitting any surface rust with mechanical cleaning and then spraying with their Matte Rust Encapsulator, then painting or undercoating.

Here's the link to the stuff I use:
https://www.eastwood.com/eastwood-r...W400iJ1c4_S7dyMCUkMMsm0nCykNxHNxoCsVEQAvD_BwE

For the foam, any closed-cell "marine" foam would work well. You would have to get creative with barriers and forms (aluminum foil and balsa wood are handy for boat hulls!), but would be manageable. Here's some stuff that works well: https://www.imperialsupplies.com/item/9266012

 

[JeepJeezy]

For an encapsulator, paint, and similar stuff, I like Eastwood products.

I like Eastwood products! POR15 has worked wonders for me in the past. @Jayc4929 Can you remove the undercoating? That's the worst thing to do to your underside. It traps moisture and promotes rust underneath it. Before it gets cold out, I pressure wash the whole underside, let it dry, they apply Fluid Film. Keeps the salt off and the rust away!

 

[Jayc4929]

For an encapsulator, paint, and similar stuff, I like Eastwood products. I'm currently working on my JKU and am cleaning and sealing BEFORE it becomes an issue (https://wranglerjkforum.net/threads/2008-jku-argenta-build-thread.32367/post-471207). I'm hitting any surface rust with mechanical cleaning and then spraying with their Matte Rust Encapsulator, then painting or undercoating.

Here's the link to the stuff I use:
https://www.eastwood.com/eastwood-r...W400iJ1c4_S7dyMCUkMMsm0nCykNxHNxoCsVEQAvD_BwE

For the foam, any closed-cell "marine" foam would work well. You would have to get creative with barriers and forms (aluminum foil and balsa wood are handy for boat hulls!), but would be manageable. Here's some stuff that works well: https://www.imperialsupplies.com/item/9266012

I actually was just at the mechanic shop today and had them take a look at my undercarriage and brought up your idea with the foam. While they did sat they've seen it done, they didn't recommend doing that as it would end up holding moisture in as well and rot from the inside. Have you found this to be an issue. As for the rest of the undercarriage, they said frame is actually in pretty good condition with just surface rust. But as I said the dealership told me originally that they put preventative on as well as fluid film before I drove it off lot. Although they didn't clean off old flaking rust beforehand so it's all just flaking off. Also on a side note, found all of my body mounts are pretty much gone!! AND my aftermarket headlights and tail lights are not DOT approved and wont pass inspection. I cant believe i didn't pay enough attention to this thing before I bought it.

 

[pc1p]

I actually was just at the mechanic shop today and had them take a look at my undercarriage and brought up your idea with the foam. While they did sat they've seen it done, they didn't recommend doing that as it would end up holding moisture in as well and rot from the inside. Have you found this to be an issue. As for the rest of the undercarriage, they said frame is actually in pretty good condition with just surface rust. But as I said the dealership told me originally that they put preventative on as well as fluid film before I drove it off lot. Although they didn't clean off old flaking rust beforehand so it's all just flaking off. Also on a side note, found all of my body mounts are pretty much gone!! AND my aftermarket headlights and tail lights are not DOT approved and wont pass inspection. I cant believe i didn't pay enough attention to this thing before I bought it.

If you use a closed-cell foam and coat the metal below, it would hold any moisture. Closed-cell foam is what they use to make boats out of and won't inherently hold moisture. Still, the prudent thing to do would be to encapsulate BEFORE foam coating, which further ensures moisture protection. Remember, your JK already has pockets of closed-cell foam between the inner panels behind the rear wheelwells.

The dealer could put 15 gallons of Fluid Film on there but it won't matter if the cancer is already started and it's flaking off. Personally, I've never been a huge fan of Fluid Film. It's messy and always seems to get places I don't want it to. For me, I clean thoroughly each spring, touch-up and coat before winter every year. With proper surface prep and quality materials, you won't need to do to much each year.

Don't beat yourself up too much - it's easy to get excited when buying a new rig and overlook otherwise red flags

 

[pc1p]

Can you remove the undercoating? That's the worst thing to do to your underside. It traps moisture and promotes rust underneath it.

I have to disagree with this. This is an Old Wives Tale from the guys that sell Fluid Film and other oil-based products lol... seriously though, I think most of these reports come from people who were already trying to cover-up cancerous rust, or used so much material (the "more is better" logic) that they plugged up drain holes in tubs or frames, which will indeed exacerbate rust issues.

I grew up in the northeast and deal with snow and salt routinely. We heard stuff like this for years and despite working in a body shop for a number of summers in the late 90's, I've never seen this be the case, nor have I ever found an example of where the undercoating has "bubbled" and held water inside (which I've heard many times as a potential issue but again, have never once seen - EVER - despite decades of working on cars in the rust belt).

Properly prepped and applied, rubberized undercoating is significantly more durable that most chassis paints and works perfectly on tubs, wheelwells, and similar. I don't usually do the frame in undercoating because the frame isn't often peppered with rocks or salt pieces. Instead, a good chassis or epoxy paint has proven to be the most effective there.

 

[Jayc4929]

I like Eastwood products! POR15 has worked wonders for me in the past. @Jayc4929 Can you remove the undercoating? That's the worst thing to do to your underside. It traps moisture and promotes rust underneath it. Before it gets cold out, I pressure wash the whole underside, let it dry, they apply Fluid Film. Keeps the salt off and the rust away!

I was told that that undercoating was rust preventative and fluid film. The dealer that did it before I drove it off the lot put it on 5 months ago but put it on over the top of the flaking rust. Didn't clean it first, so it's all just flaking off. Im thinking I need to get under and wire brush everything I can and that put some kind of rust inhibitor like PCP1 stated

 

[Jayc4929]

For an encapsulator, paint, and similar stuff, I like Eastwood products. I'm currently working on my JKU and am cleaning and sealing BEFORE it becomes an issue (https://wranglerjkforum.net/threads/2008-jku-argenta-build-thread.32367/post-471207). I'm hitting any surface rust with mechanical cleaning and then spraying with their Matte Rust Encapsulator, then painting or undercoating.

Here's the link to the stuff I use:
https://www.eastwood.com/eastwood-r...W400iJ1c4_S7dyMCUkMMsm0nCykNxHNxoCsVEQAvD_BwE

For the foam, any closed-cell "marine" foam would work well. You would have to get creative with barriers and forms (aluminum foil and balsa wood are handy for boat hulls!), but would be manageable. Here's some stuff that works well

so do you recommend a good mechanical cleaning solution spray or should I just wire brush loose rust and encapsulate spray paint it?

 

[Jayc4929]

If you use a closed-cell foam and coat the metal below, it would hold any moisture. Closed-cell foam is what they use to make boats out of and won't inherently hold moisture. Still, the prudent thing to do would be to encapsulate BEFORE foam coating, which further ensures moisture protection. Remember, your JK already has pockets of closed-cell foam between the inner panels behind the rear wheelwells.

The dealer could put 15 gallons of Fluid Film on there but it won't matter if the cancer is already started and it's flaking off. Personally, I've never been a huge fan of Fluid Film. It's messy and always seems to get places I don't want it to. For me, I clean thoroughly each spring, touch-up and coat before winter every year. With proper surface prep and quality materials, you won't need to do to much each year.

Don't beat yourself up too much - it's easy to get excited when buying a new rig and overlook otherwise red flags

What do you recommend for surface prep on mine before putting on encapsulator paint? Also, would 2 cans of your previous suggestion cover most? So fluid film doesn't go over the encapsulator paint?

 

[pc1p]

What do you recommend for surface prep on mine before putting on encapsulator paint? Also, would 2 cans of your previous suggestion cover most? So fluid film doesn't go over the encapsulator paint?

You will need to mechanically remove the flaking rust. The easiest way to do it is to use a needle scaler and go to town. I have this one and surprisingly, it works as good as the fancy one I used many years ago: https://www.harborfreight.com/compact-air-needle-scaler-58646.html?hftm_sc=820&utm_source=google&utm_source=google&utm_medium=cpc&utm_campaign=22880249704&campaignid=22880249704&utm_content=185070214273&adsetid=185070214273&product=58646&gad_source=1&gad_campaignid=22880249704&gbraid=0AAAAADAHb4efSX6RLMTlAFtz_KHit9ULC&gclid=CjwKCAjwxrLHBhA2EiwAu9EdM15vy-aj2s33sS02LtkNx0ry9BHB9rCV41DtkwisgUxnA3BXp1GBIxoCrCgQAvD_BwE

You need to get some safety glasses on and get in there and get every loose bit of rust needled off that you can. It can be tedious and time consuming, but it's really the only thing that works for flaky rust. At that point, I would coat with the rust encapsulator plus (https://www.eastwood.com/eastwood-rust-encapsulator-plus.html). This has higher than typical zinc levels that offers galvanic protection to the metal and prevents the spread of rust even better than the regular formula.

I suppose you could use something like Fluid Film on top of the encapsulator, but it would be a waste since I don't think the material will really be doing anything at that point except floating on the encapsulated surface. Given the area that this is in, the rubberized rust encapsulator may offer better protection and some additional rigidity that could help the base material, though if you're going to use foam to provide some structural rigidity, I wouldn't bother.

 

[tJKrider]

I've never been a huge fan of Fluid Film. It's messy and always seems to get places I don't want it to. For me, I clean thoroughly each spring, touch-up and coat before winter every year.

This has been my strategy as well with a decent rattle can paint. It works remarkably well, imo, and doesn't come with the issues of other coatings.