I have been reading some of the other posts on this site about repainting their backhoes. My Backhoe is pretty crusty and is in need of a paint job too. My question today is about the cylinders. Most of the cylinders on my machine need seal kits. My Question is: Do I tape up the rod, sandblast, spray the cylinder with primer, put in the new seal kit, then spray on the top coat of paint? or Should I put in the seal kit then sand blast the cylinder, and then prime and paint?
Cover the rods with the old seals in them, blast, repaint them entirely (primer and paint), and then install new seals. No sense in worrying about damaging the new seals, or degreasing once for primer, and again for paint. It's worth checking if someone in your area does blasting with dry ice. We've used it on large printing presses in factories with ungodly amounts of bearings on them. Not a single one went bad due to sand getting into them, and all of the leftover ice evaporates, leaving only paint chips behind. No dust to clean up from the sand and no blasting media to dispose of
Well I see it a bit differently than rossaroni. Replacing seals require the type of work that's hard on paint. If you have an old Case you may need to peen the cylinder end with a hammer or maybe even use a torch. I decided to reseal all my cylinders before any painting prep began. I would do it again in the same order. Yes you need to be careful of the seals/cylinders etc. but at least when your done the paint will stay put for a while. Also you must keep in mind that new paint is not very resilient to scuffing and scraping.
Thank you to both of you for the input, both of your views have strong points. Although I like the idea of blasting with dry ice and painting, these cylinders have been together for the last 45 years and I may need to use some heat to get them apart. Maybe the better plan is to combine both of your ideas and reseal the cylinders and then blast them with dry ice. Now I need to find someone that can blast with dry ice. Thanks again.
When I rebuilt my cylinders did not use heat - was told by a local rebuilder to lay the end on a hard surface (anvil) and hammer with moderate force around the thread area of the gland nut. Start 1" back from seal and hammer a pattern (10 or so blows) away from eye for a about 2 1/2 " depending on size of ram. Rotate cylinder a few degrees and repeat all the way around. All my gland nuts then spun off with no problem. Only on one did I repeat the process. Bob
I would definitely rebuild before refinishing. One thing to add, if you have leaking cylinders, make sure to inspect them closely and thoroughly to make sure it's actually the rod seals or gland o-ring leaking and not a crack in the barrel or hydraulic port. A lot of Case cylinders have issues with the cast elbows on the ends of the cylinder. Only way to fix is replace the barrel, or have a cylinder shop cut the ends off and rebuild the barrel. Don't ask how I know.
Try Mavo. They use dry ice blasting in fire damaged buildings to remove catilized fireproofing and soot, etc. I believe they are all over the midwest. Maybe you can work out a deal if you can haul it to them. Dry ice blasting is the cats meow but its not cheap.