Car mechanics not afraid of rust

April 26, 2019 8:50 AM

As a car owner for the first time in 15 years, I have some anxiety about maintenance. Especially because the mechanic who looked at the car right after I bought it (early 2010s Honda Fit) said that the rust in the undercarriage was dire and not something he could deal with. Are there mechanics who can work around rusted undercarriage? Do I need to drive out to South Dakota to find one?

Two questions
1) Anyone anywhere, especially in snowy areas where they salt the roads. Is rust really so terrible? How does your car repair shop deal with rusty undercarriages?
2) LA County people (especially those on the north and eastern side of the county) can you recommend a mechanic who can handle rust? I'm guessing most mechanics in California will not have as much experience dealing with rust as a mechanic in the Midwest or New England.

It's not obvious why the car has so much rust underneath but speculating it came from a city with snow? Mold isn't an issue so I am ruling out hurricane flooded cities for now.

I'm currently anxious about the suspension (why is the 10 between Claremont and Baldwin Park so bumpy?!). Which leads me back to thinking I need a mechanic who will be willing to deal with the rust.

posted by spamandkimchi to Travel & Transportation (13 answers total)

The rust isn't "in the way". A mechanic doing what they need to do isn't impacted by the rusty undercarriage. "Not something he could deal with" I take to mean he's not a body shop, not that he can't maintain your car mechanically.
posted by humboldt32 at 9:04 AM on April 26, 2019 [2 favorites]

Cars from areas where they salt the roads will have lots of rust. It makes everything much more difficult to deal with. Bolts will break or need to be cut off. New parts wont fit because the mating part has changed shape. And so on. Its a huge pain in the ass.

Depending on how well it was maintained, your car could be pretty hard to work on. Not impossible, but... If you're not used to dealing with it, it would be an extra hassle with a non -zero possibility of extra work as things break.
posted by Pogo_Fuzzybutt at 9:14 AM on April 26, 2019 [4 favorites]

Best answer: "Rusty undercarriage" can mean a wide range of things. If the structural members of the unibody are seriously compromised by rust, the car is unsafe and essentially scrap as repairs would exceed the value of the car. If removable subframes and such are corroded through, they can be replaced, though it's expensive and often a huge hassle. If the mechanic is just grousing about it being difficult to work on the car due to corroded hardware (on preview, what Pogo Fuzzybutt said) that's something which can be dealt with but requires extra skill. Rather than just unbolting a (for example) lower control arm, you're taking a welding torch, cutting through nuts and bolts etc, or spending hours trying to remove some corroded part without breaking it.
posted by Larry David Syndrome at 9:16 AM on April 26, 2019 [3 favorites]

Find another mechanic and get a second opinion. It would be very unusual for a 9 year old car to have severe rust. Cars are constructed with much better rust proofing than even a couple of decades ago - even for cars from the salty northeast.

You can do a Carfax search on your car's VIN that might give you an indication of whether your car had an unusual history, such as salvage.
posted by JackFlash at 9:24 AM on April 26, 2019 [7 favorites]

In L.A.? Go to the 76 station on Hollywood blvd. just west of the strip...ask for Milo. He will hook you up. He took care of my '89 Olds for many years and his prices are fair. My car was $200 and very thrashed in general and he kept it running and reliable well past its expiration date.
Also, the book 'car repair for dummies' is really useful for diagnosis and helping to ward off bullshitting (ie getting a quote to replace the engine when you know it's just a belt)
posted by sexyrobot at 9:33 AM on April 26, 2019 [6 favorites]

Best answer: Yeah, mechanics don't really deal with rust, that's more of a body shop and/or paint shop issue.

Any mechanic ought to be able to work on a rusty car, although it can be sort of a pain in the ass (fasteners get frozen and are difficult to remove, often requiring replacement; this can drive up the cost and time involved in a procedure) but they're probably not going to be able to fix the rust itself.

For that—which is worth doing, if you are going to hang onto the car—you want to go to a body shop that does paint work. Not because you're actually getting the visible parts of the car painted, but because they'll have the proper equipment to remove the rust and then paint the underlying metal. (You can also DIY this if you want to, it's not brain surgery or anything. You basically want to wire-brush the loose rust and any flaking paint off, then use rust-converting primer, then topcoat with something cheap to protect the primer. I used to do the undercarriage of my rust-plagued Jeep with grey Rustoleum primer and flat black Rustoleum paint. I didn't even do much masking, except to the hot exhaust parts and brake discs. It's a filthy job because you have to be under the car as you're brushing the rust off—wear a dust mask!—but not difficult. And body shops can be expensive.)

If you have trouble finding a local place that will do this, find a body shop that works on off-road vehicles. They will probably be used to doing all sorts of undercarriage work.
posted by Kadin2048 at 11:18 AM on April 26, 2019 [1 favorite]

did the mechanic say rust wasn't something they could deal with in response to the question "can you fix this rust?" or did they say it in response to you asking for something car mechanics normally fix to be fixed?

because if the former, that's just the mechanic saying "i don't do bodywork."
posted by zippy at 12:11 PM on April 26, 2019 [2 favorites]

Best answer: Anecdote: I loved my 2008 Honda Fit, but rust had undermined the undercarriage by late 2017 (I think they said the rocker panels had become structurally unsound, or something like that). I never talked to a body shop about it. I live on a dirt road in Vermont--definitely not a good environment for a car's undercarriage (mud plus salt plus ice)--but I was pretty disappointed. The Fit rides pretty low to the ground, which might have exacerbated the issue.
posted by baseballpajamas at 1:03 PM on April 26, 2019 [1 favorite]

Best answer: I will add: California mechanics are wimps. I bought a Subaru Forester in NYC and drove it around New England for years. I took very good care of it and my northeastern mechanic thought it was relatively rust-free given it's age. When I moved to Oakland mechanics would regularaly scoff and refuse to service it. You'll find someone who can handle it.
posted by thebigdeadwaltz at 1:04 PM on April 26, 2019 [2 favorites]

I'm not saying this is your car (I'd almost guarantee it's not) -- seriously, you need to a) find out exactly what the mechanic meant by his comment to determine if it's his dislike of working around rust or if it's a compromising structural issue and b) likely find another mechanic assuming it's just his general perference -- but rusty Hondas are a problem serious enough to warrant a recall in certain parts of Canada.
posted by sardonyx at 3:52 PM on April 26, 2019 [1 favorite]

Response by poster: In response to zippy, it was the mechanic saying "the rust is a problem for you, when your car has a real problem to fix, it will be hard to fix because the rust corrosion." He went as far as to say we shouldn't expect the car to be in decent driving condition more than a year or two. It seemed like basically it would be really hard for him to work around all the corrosion on the frame, like what Larry David Syndrome and spitbull were talking about.
posted by spamandkimchi at 5:32 PM on April 26, 2019 [1 favorite]

Is rust really so terrible?

Yes-- it's never cured, only arrested for a while.

How does your car repair shop deal with rusty undercarriages?

Depends on the shop -- those that restore classic cars deal with rust most effectively by cutting out the affected areas and welding in shiny new steel.
posted by Rash at 5:14 PM on April 28, 2019

We have our car's undercoated with a lanolin-based product and it helps keep the rust at bay here in Vermont.
posted by terrapin at 12:58 PM on April 29, 2019