Hi I started my floor pan project and figured I might share some of my adventures so far. I'm far from an expert in body work, so if nothing else you might see at least something about what NOT to do Before settling on this machine I looked at several 580/590 machines. I noticed a trend of horribly rotted cabs and floor pans, along with numerous people online echoing that these things have a tendency to rot away. It surprises me how floor plates that look like they're 1/8" thick could rot out seemingly so easily but it is what it is. My K has decent floors for an older machine in the salt belt. The left floor is heavily pitted, but not rotted, and the right has some minor rust/pitting. The right fender has zero rust but the left fender has rust on the interior all along the seam where the fender meets the floor pan, with rot in the area forward of the roll bar up to where the arch meets the floor. There was a small spot of perforation through the fender midway in this area in a small spot. I assume the left side gets much more rust from foot traffic/salt because of the shifter on the right side. I want to repair the rot on the fender and limit further deterioration. My project started by stripping the interior of the floor contact items. First I removed the seat and its pedestal as an assembly. That assembly is surprisingly heavy for just a single seat and wrestling it out of the machine solo without injury to the machine or self was interesting. This is the interior without the seat: https://www.dropbox.com/s/76za2k2gjum212x/1.PNG?dl=0 This is the most troubled area, the left side floor and fender. https://www.dropbox.com/s/stfbq38jjst11d3/2.png?dl=0 Close up of the rot on the left fender. A horizontal cut was later made above the rust hole running from just before the front arch to back just behind the brown plastic trim (more on that later). https://www.dropbox.com/s/948z6dqhu31iknk/2b.PNG?dl=0 I removed all of the interior plastic trim, consoles, and backhoe foot rest/pedals. Next I removed the floor plates that cover the front of the transaxle up to the pedals and the one that covers the backhoe hydraulic valves. I took these out so I can treat as much of the floor as possible- I want to get paint all up in the seams and whatnot. About a half dozen of the countersunk Allen bolts that hold these plates were seized and had to be drilled out. I do not know why they chose to use these types of bolts that have such a tiny Allen bits to grip a rather large bolt subjected to floor traffic and grime but this is going to have to change when I put new ones in. With the majority of the interior out I went in there with a pressure washer to blast out the worst of the accumulation of dirt, grime, mouse nest, dog fur (?), and who knows what else that has accumulated for the last 30 years in this thing. It looks like this machine had an old leak in the master cyls as the area below the brake pedals was caked up with oil/dirt/whatever. The pressure washer may not have been the best route as I made an incredible mess and splattered gunk everywhere on myself and the windows, but it sort of worked worked. After that I went on several stages of brushing and shop vac, followed by using a side grinder with a steel wire wheel. The below are a few progression shots. This is the left side of the machine after brushing and vac: https://www.dropbox.com/s/i1e2g4f6v5nrpli/3.PNG?dl=0 Close-up of the worst of the pitting. It is interesting that the non-skid-taped area that I scraped off shows almost perfect metal in the middle strip. I wonder if they used more of this on the machine if the floors would have lasted longer! https://www.dropbox.com/s/t6dovvs5y82fayj/4a.PNG?dl=0 Wire wheel of the pitting: https://www.dropbox.com/s/ytj99b2oupndj75/4b.PNG?dl=0 Shot of the same area after application of the rust inhibitor/acid. https://www.dropbox.com/s/n3wukafrfcytcny/4c.png?dl=0 This is from the left looking towards the back of the cab. The treatment of the pitting is dried and I started working on the fender area that rotted. I didn't get any before pictures but I did get a picture after the first coat of paint later. https://www.dropbox.com/s/adb4awqqiv8yzsw/5.PNG?dl=0 After I lost count of how many sessions of cleaning with the brushes, vac, MEK, brush, MEK, vac, (repeat), I did my first crash-coat of paint. I say crash coat because it was getting late, I was tired, and this is just wanted to get the first coating on the main wear areas and prevent any flash rust anywhere with rain in the forecast. I will end up touching up other areas and painting more up along the fenders on the second coat. I'm using a product similar to POR-15 that is moisture cured and is supposed to pull moisture out of the metal surface as it cures. I'm hopeful that the saturation of this product on the floor will give a good base layer for a follow up coating and eventually a top coat. https://www.dropbox.com/s/9wm98fvtzhhwqdq/6.PNG?dl=0 This is a shot of the troubled fender. The picture is an awful shot and a rotated crop. Basically I cut out all of the rotted metal that ran from just in front of the roll bar to just before the arch. I'm going to make a few more minor cuts to clean this up, touch up with paint, then cut a 2" angle iron section to patch from the vertical fender wall to the floor pan. I plan on painting the angle before I put it in and then rivet it in place to secure the fender back into the floor. Then encapsulate that with another layer of paint. I was thinking of welding it in but I'm paranoid about welds and rust so I figure riveting it into place will be fine and maybe less likely to create rust either inside or outside of the fender. https://www.dropbox.com/s/2pc24tk4iz5fb3f/7.png?dl=0 This is my first stab at the project. I'm going to put another coat or two of the primer paint and then top coat with a 2 part bedliner product. I have had good experience with Monsta liner as interior and exterior paint in my trucks. I think that the 2 part paint works well for hardness and durability. It can also be tinted various colors so that's a bonus, too. After that I need to figure out what sort of floor mats I can use in it. I think maybe a pickup mat cut into a shape would work in there. So that's my progress so far. I will update this thread as I get the time to work on this.
Big project. Nice work! I hate dealing with rust . For the mat... I've seen some rubber mat at Tractor Supply for horse areas comes in large sheets. I have the mat out of mine for other repairs and will need to paint before it goes back in. I power washed the inside too !
I have had terrific luck with POR-15. The stuff is impossible to get off your skin or anything else once it cures. The stuff is not UV stable so places where the sun hits it you need to top coat it. Underneath the stuff is fine by itself. It is not cheap but it does work. My Cat 426 has rust on the cab. The floor is particularly bad. I plan to, when the weather warms up, to remove the rusty stuff, descale and paint with POR-15. Then I will replace/fabricate replacement parts. Does not need to be a restoration just need things functional.
Thanks Highway. Yeah the rust is a constant battle in the Northern states. I saw those mats at TSC. I'll have to check it out again to see if they'll work. Edgephoto - POR is a good product and I've had good luck with it too. The product I am using is very similar to it. It is the same type of moisture cured paint and because of that it's impossible to get off your hands! . I painted up the "A" pillars about 6" with the primer to try to limit any corrosion/rust from salt creeping up the pillars. These paints seem to do a great job of sealing things up.
I had some time to continue this project recently and figured I'd share. During this project I discovered some considerable wiring issues with the connectors under the floor. The 4 connectors between the cab harness to chassis harness were completely gone, which significantly delayed putting everything back together. Thankfully this explains the wiring gremlins I was planning on tackling anyway. More on that later. So, the floor project is pretty much done now. After the primer cured I sprayed rattle can Rustoleum bed liner as a top coat to give it some grip. I was planning on using something nicer like a 2-part stuff but I just needed to get this done. I might topcoat it with something someday but so far I'm pretty happy with how it came out. The other item I addressed while I was here was to replace whatever putty/paste Case put between the floor pan and the floor plates with rubber strips. At certain RPM, particularly low-idle, the floor pans would start a symphony rattle trap orchestra from hell (thank you large 4cyl diesel engine with no balance shafts!). With the rubber strips it is now nice and quiet at any RPM. This is a picture of the strips I cut and glued to the underside of the plate. I did the same on the other two plates: Here is a shot of the repaired left-side fender with the angle iron rivet into place. It isn't pretty, but I think it is going to be fine: While I had the floor up I replaced the clips and tiny allen bolts with these and zinc-plated giant phillips head screws: Also while I had the interior plastic consoles out, I figured I had to change the faded-brown plastic to something else. I went with this "soft iron" paint and I like how it came out The paint is gray with a little bit of flake in it. I think it looks nice, even if it isn't the 'correct' color scheme for a Case of this era: The seat was also totally beat out so I replaced that. While the consoles were out I figured I might as well add a cigarette lighter and two USB ports to be able to charge any accessories I might want to use. I did not take any pictures of that but it's pretty self explanatory. I also ended up priming and lining a bit up from the floor to the dash/a-pillars. Unfortunately, the paint creeped under my tape line so I might want to clean it the edge a bit at some point. I'm not sure if I'm going to keep the brown or change it. I've been considering doing the same gray paint on that. Eventually I will also paint the plastic "dash" pieces, but that is for another day. This was just about rust prevention: Back to the wiring issue, this is what I found. Not only are the connectors right next to the tire area where it seems they'd get water splashed/hazed on them, but they aren't even sealed. They also don't have any locks/catches. So on mine they left a tiny crack for air to oxidize them and eventually completely rot out. Not just a little coroded, literally rotted through. The positive 12v lines/lugs literally fell apart when I unplugged them! I also found out they must have gotten super hot as the insulation on them was melted in some areas and it was difficult to strip them during the wiring extensions, I suspect due to the poor connections. Gone! I ended up cutting all of the plugs off of the chassis harness as they were not savable. Then I soldered in extensions on both the cab and chassis harnesses, heat shrink, taping that, and then plastic coil wrap for abrasion resistance. The extensions allowed me to relocate all of the connectors inside the cab, above the floor pan and inside the side console. For replacement connectors I went with Deutsch connectors which are sealed and snap/lock together. This was probably more than a bit overkill, but I did not want to have to revisit this again. I think that Case could probably have avoided a lot of these wiring issues had they just located the wiring in the cab/console in the first place (or used sealed connectors), but now I hope this upgrade will outlast the rest of the machine. So that was my floor/wiring project and hopefully it may be helpful or interesting to anyone else planning on tackling something similar. I should probably get around to getting a picture showing the whole thing instead of just bits and pieces, but that will be for another day. Right now I'm working on replacing the seals in the backhoe boom and dipper cylinders that just gave up on me. It seems there is "always something" that needs TLC, particularly on an older machine.
Nice work. You are inspiring me to deal with the rust in my cab. I have a Cat 426 and the seat pedestal is wobbly and I need to disassemble and figure out how to fix it. FYI, for future reference, there is heat shrink tubing you can buy that has a sealer inside so once you shrink it it makes the connection weather tight.
Thanks Edge. From what I understand, the Case K model has a particular and serious propensity to rust. I thought this was mostly isolated to this machine, but I'm not familiar with the others. Does the Cat have the same same? It still kind of surprises me to think that these thick plates of steel would rust through so easily - almost like a bad alloy of steel or something. There are definitely some seams that I think could trap salt and moisture which can't help, but even still it surprises me how far gone I've seen some of these Ks when I would imagine that their salt exposure is not as severe as a car (made of super thin sheet metal) that is moving down the road at high speed and driving through aerated clouds of salt water. I've seen the weather tight shrink stuff and even wire nuts with dielectric grease in them, but I don't know I'm just weary of using that by itself even if that is not a rational concern. I hate dealing with flaky connections and wiring gremlins. For this I used the shrink on each line, then did electrical tape wrapping running from before and after the shrink wrap on each line to help give it some extra sealant, then bundled the wires together as a common cord with tape before topping that with the plastic spiral wrap to armor it. It might not be the prettiest looking thing, but I've had good luck with quality electrical tape making a good sealed connection in the past so I figured this should work. I'm hopeful it will be way ahead of the factory setup, especially with those plugs that are hopelessly exposed/unlocked/unsealed.
I am no expert on coatings, but I think how well a machine lasts over time is largely due to the quality of that initial coating and, of course, what the material is exposed to. I work for a drilling company and we use a very high quality, Sherwin-Williams two-part paint system that generally holds up very well. We have some rigs that are 10-15 years old, working nearly every day of their life that still look great, others, that were exposed to harsh drilling fluids like brine and some caustics that just look terrible. My Case 590 SL is an open cab and still looks very good considering it spent most of its prior life on the East Coast and outside - very little rust. My Bobcat, which came from PA, is much newer but looked very bad when I first got it. A lot of wire brushing and new paint and it looks a lot better, but still flaking off in some areas.
From what I can tell the Cat 426s were prone to rust in the cab doors and stuff.