I went to get my '79 Catalina's wheels aligned on Saturday. They advised me that the idler arm is worn and will need replaced, and that the sway bar links are bad. I've never messed with steering linkages before, is this something a DIY guy can do with a service manual, or is that something only a more professional mechanic should mess with? I replaced sway bar the links today, one was missing, the other was so rusted together I cut it out with a grinder.
I've replaced idler arms, it's definitely doable though rust may make the job more difficult than it would be otherwise. Remember heat from a torch is your friend and if you are replacing the old part you don't care about ruining it.
That was my attitude toward that ancient sway bar link. I did the job in about 30 minutes thanks to my grinder. Haha. I have phosphoric acid based rust remover gel from Rust-o-leum I could apply to the bolts holding that idler arm to the chassis. Would that be a good idea, or just use a propane torch?
The gel will help get rid of rust on the surface but won't penetrate the threads. I'd attack it with a combination of that stuff, penetrating oil, heat, and whacking it with a hammer. It can also help to tighten slightly before loosening to help break corrosion in the threads. Be careful though not to break any bolts since that's another level of hurt to deal with.