Corrosion

I did some updates to my i-MiEV this weekend and needed to remove the motor cover. After taking the cover off, I found salt deposits around the lip. Must have happened during the winter when they sprayed salt on the roads. In Ontario they are using less and less of the stuff but its still being used. I also found several exposed bolts corroded and corrosion around all of the bolts on the inverter and DC/DC converter covers (white deposits). Some paint was knocked off the frame rails on the left rear tire - I know it's not a frame per say, but its some type of square steel tubing holding up the back of the car and providing attachment for the shocks and springs. I also found corrosion in the rear bumper steel - it's like two pieces of thick steel welded together, between this sandwich I found the beginning of rust. I had the rear of the car up on the ramps so I could take a good look around. I didn't have enough time to clean all of this up, so I'll have to revisit it another time.

I want to keep the car a good long time and salt is a real enemy around the North East and Mid West and else where. Just wanted everyone to be aware and take note. I also find the paint to be quite thin in all places on the car, I keep a good solid coat of wax on this throughout the winter and summer.

This is something that I worry about in terms of the longevity of the car, since I live in the 'rust belt' as well, and small cars tend not to do very well in that regard around here.
I've had pretty good results with oil-based rustproofing significantly slowing down the rusting pace on cars in the past (my previous car had very few rusty areas at 18 years old). What are your thoughts about applying this type of rust proofing on the i-MiEV? I would definitely request that they stay away from the battery and electrical cables, mostly focusing on the inside of the body panels, and the chassis.
The dealer where I had bought my i had tried to sell me a rustproofing package (don't even know what type), but I declined.

There are a couple of things to do. You need to get the salt off the car and neturalize anything that stays on. There is a product called "salt away" that is basically used in marine engines to help flush the salt out. It can be sprayed on with a garden hose after you have washed with soap (important) and water all of the components and the underbody. If you are using a self serve carwash, keep the high pressure away from connectors but otherwise get it clean. If you want to keep the aluminium parts nice, after everything dries, spray those parts with either "Corrosion Block" or "Corrosion X". These products should be available from either a marine or aircraft supply.

I put the car up on ramps yesterday and inspected the undercarriage for corrosion and found plenty. Most notable the parts that face forward and get a high-speed scouring of road hash made up of salt and sand - what a combination! The forward facing parts of the lower control arms and some brackets at the front of the battery pack had bubbling paint and notable rust on the metal surfaces. The framing is made up of tubing and many of the welds were exposed and the black paint was flaked off. All of the bolts had corrosion.

I took my wire brush and scraped off the paint and rust down to bare metal. Then washed and cleaned the underbody with a slightly moist rag to removed any debris. I followed this with a coating of self-etching primer on all metal surfaces; control arms, framing, some of the stabilizer bar, metal brackets holding up the battery pack, the open spaces between the battery pack and the sills. Covered all of that up with Pro-Grip (Rustoleum's answer to Plasti-dip).

This winter I'll take siai47's advice and get Salt-Away and be sure to spray the underbody with that. I've read a bit about that product and the nice part is that it leaves a coating if not rinsed to prevent any further corrosion.

I have to say the only nitpick I have about this car is the very thin paint job on it. It seems like I just look at the car and get another scratch or gouge in it.

If you really want to get upset about corrossion, I would think that removing the plastic panels under the battery pack would be a real eye opener after a salty winter in Northern climates. My brand new I-MiEV was already showing signs of rust under the panels when it was delivered new. Just the time it sat on the coast at the port had already corroded the motor and gearbox housing. When I dropped the panels, there was a lot of dirt and sand under them along with surface rust---and this car had less then 30 miles on it. At the end of each winter season, I would remove those panels and flush out the area around the pack----no high pressure, just a good rinse with soap and water followed by some saltaway at the end. I know water and electricity don't mix but salt water and electricity is worse. Just be careful around connectors and at the top rear area of the pack as there is a vent up there. The housing for the pack is thermoplastic (and therefore won't rust) but the frame that holds in in many areas is just sheet metal with a very thin coat of paint. To make matters worse, this frame is pressed up against a stainless steel screen (Farady cage) that will lead to dissimilar metal corrosion with the plain steel getting the worst of it. This is what is going to rust to the point of structual failure if it is not maintained. As far as the body sheetmetal, I think that the paint thickness and quality is better then a lot of new cars I have seen. When you look underneath the car, you will see that there is a great primer coat throughout the entire structure. The body primer looks like it might be dipped or at a minimum it is electrostaticly applied. As far as a top coat goes, (at least on the two I-MiEV's that I have) I find pretty good paint coverage---especially if you look at the bottoms of the doors and rocker panels compared to other cars.

I'm also worried about the rocker panels along the sides of the car, hoping no saltwater gets into that area. Probably next season I'll take them off and inspect for corrosion. I did see some seals along the outside edges. Hope that holds up.

I keep the outside of the car waxed throughout the winter season and I know that has helped.

Thanks for the advice on this. You own two i-MiEVs? How cool.

This thread is close to my heart, as I have always owned older cars and fighting rust is always a big deal. As to the question MLucas posed, regarding the oil treatment to a new car, My opinion is a resounding yes. The trouble spots are always where two layers of steel are sandwiched together and moisture can be trapped. I would soak these areas and fill them with either the specialty products that are available, or even simply straight 30W motor oil [essentially chain saw bar oil.] I did this when my '92 F150 pickup was new and today I think have the only 22 year old pickup truck in NY without holes on top of the rear wheel wells in the bed.

Mike

Isolating the doors I found the rear doors ok but the drivers side compartment was wet. It was the plastic part only, nothing inside the door. On my wifes side the ankle attaching the plastic armrest to the door has rust on it but nothing wet.

The water in the drivers door most likely comes from me wearing shorts even in winter. But were comes the rust in Karins door from? I'll try a rust converter on it. Looks mostly harmless right now.

Cheers
Peter and Karin

Our car is 'new'. A 2012 model we bought with 150km on the odometer. It was a demo, only licensed in Feb this year. I find the car generally "lightly built". This is no surprise but I want to keep it for a long time and Ontario winters are hard on any car. Hence I am thinking about rustproofing it. I am especially concerned about areas you can't see like the doors (inside) and the rocker panel cavity. Our 2003 Corolla was under coated with some drip-type oil product and re-coated for the first five years of our 13 years of ownership. The dripping was quite an inconvenience but this stuff found its way into the various nooks and crannies where water likes to go. Now our son drives her and it looks fantastic.

There arena lot of good ideas above, but some are not very practical unless you have a ramp to lift the car. My question is did anyone had their "i" under-coated? What product did they use?

Also, does Mitsubishi has an opinion on undercoating this car? My Toyota dealer told me not to undercoate the Prius!!

Laszlo

I had my car done by this guy

Louis Caron
6056 Rue Anthony
Brossard, QC J4Z 1L7


He shoots grease. It stays I place mostly but the car does ooze grease forever. He opens the doors up and shoots the inside as well as the entire underbody. It's more epensive then the yearly oil treatment but it's one treatment when the car is new and then a re shoot after 3 years for free and that's it.

I did this on a 1986 honda civic crx and I owned and ran it in montreal for 18 years before I had to put it down. It was rusted in spots but the body was mostly good. I totally outgrew they car but it was my first baby. I did it again on a 2001 civic is and when I traded that in on the imiev it was perfect.

Time will tell if the Kiev holds up.

Don.....

I thoroughly Waxoyled my iOn in the summer (2014) and noticed rusting to the battery pack mounts under the plastic belly pan when I took it off. I understand there is a recall on this issue in Germany? I gave the pressed steel members a good internal squirting so it'll be interesting to see what difference it makes in time.

I also sprayed the motor, controller, charger - everything really - with some trepidation in case it got hot enough to ignite or something. I took it for a fast drive afterwards and nothing was getting even vaguely hot. A couple of days later I blasted (well, as much as you can in an iOn!) up the motorway 180 miles home and checked again halfway. Still no issues. It all looks so much happier with a good coat of Waxoyl - no aluminium oxidation etc. I did all inside the 3 ply spot welded cills and inside the doors, bonnet and boot lid, too. Stank for days but it's gone now.

I have read up on the long term effects of Waxoyl on rubber an plastic and generally there appears to be no issues. MW

Hi All,

After some trepidation I have decided to have our Mitzy undercoated with a product called "CorrosionFree". Their website is http://www.corrosionfree.com/

I was able to watch most of the application at the local All Brite dealership. The product has a greasy/silicony feeling to it when touched. It is clear, it does not run, drip or smell. It was applied to cover the entire under body, and all nooks and crannies, cables, inside doors, under the plastic fenders etc.

It has a pretty good sounding warranty but I hope I never have to use it. If the car is re-treated in every 18 months the warranty covers the life of the car, assuming it is less then 3 years old - I think, maybe 2 years? Check the website.

The runny/drippy oil application (and yearly reapplication for the first 5 years) kept our 12 year old Corolla look like new. The drippy nature of the stuff make it a bit of a nonsense every year for a few days. BUT it sure worked!

Will this CorrosionFree product work as well? Only time will tell.

I just had the corrosion free coating applied for my new 2016 i-MiEV. I just had the undercoat done, not the full package with the door/trunk/lid seams, etc. Cost was $100. The shop said they'd had very good experience with it. Cars coming in after 5 years with no rust/corrosion, when applied to a new car. They even told me I shouldn't bother to come back for 5 years, and not to worry about reapplying every 18 months. I guess I'll take a good look in 18 months and see how it's holding up.

I like Loctite 633877 Extend Rust Neutralizer. Great product.

The best price with free shipping options: http://www.homedepot.com/p/Loctite-10-25-fl-oz-Extend-rust-Neutralizer-6-Pack-633877/202057888

Interesting to read the comments on this thread. I bought my used 2012 (~18,000 miles on the odometer) in November 2015 and have been driving it without incident ever since. The car spent the first two years of its (leased) life in Normal, Illinois, before getting sold to a Los Angeles dealer. It basically sat on their lot for the better part of a year before I bought it. I've given the car a couple of really good cleanings since I bought it and - with the aid of a high pressure garden hose nozzle - blasted out a significant buildup of old leaves and plant parts from the rubber-lined slots on the roof and around the taillights under the rear hatch. Other than a superficial exterior washing that may have happened at the California dealer with a cursory Armor All application to the plastic interior parts, I probably gave this car the first real detailed cleaning it had since leaving the factory.

Then couple weeks ago, just out of curiosity, I decided to pop the lid to the motor compartment. At first, I couldn't get those wingnut/Phillips fasteners to budge. So, I alternately applied some B99 biodiesel (marvelous rust inhibitor for those unfamiliar with this stuff, but keep it away from rubber) and WD40, letting that cocktail soak in for a few days. The two fasteners nearest to the bumper then came off without too much trouble ( I used a big wooden handscrew clamp to grip the wingnuts on those) but the inside ones needed more work. The one nearest to the passenger seat eventually came out (a 1 1/8" socket wrench was the perfect tool to grab hold of the wingnut edges when there wasn't room for the wood clamp,) but the driver's side one was basically rusted shut. Worse, the wingnut portion of that one was spinning freely around at this point and the Phillips head portion - with slots starting to strip badly - was still capturing the wingnut and not responding to any attempts to grab by the edges with Visegrips. I finally ground off the top of the Phillips head with a Dremel tool, pried off the free-spinning wingnut portion and then proceeded to securely grip the rest of the exposed fastener's shaft with the Visegrips, slowly and methodically spinning it out. The good news was that no threads got stripped on the car's sheet metal and the lid incurred no damage. All the fasteners had rusted thread sections. Two were completely unscathed on the top portions. The third one was dinged up slightly and the 4th, of course, was a couple of pieces scrap metal after I got through with it. At first, I replaced the 4 wingnut/Phillips lid fasteners with stainless steel M6 X 1.00 X 16mm hex head cap screws, with matching stainless washers and large diameter rubber fender washers.


(L to R) Cleanly removed fastener with rust on threads, destroyed evil 4th fastener and stainless M6 cap screw with rubber fender washer

What I found after I removed the lid gave me some pause for concern. There's a piece of matted fiberglass material mounted on the underside of the lid, held on by plastic screw-on fasteners. It's got a woven black covering as well (facing towards the motor area) and, one assumes, it's basically there for sound abatement. What it ended up doing, though, was to act as a sponge for moisture kicked up from the road surface - and I'm guessing with lots of snow and road salt at times - wicking up all this crud and pressing down onto the top of the controller and charger cover! The entire top of the motor area was covered in black-colored muck. The ribbed orange plastic wire covering tubes were completely black, as was the translucent coolant reservoir.


The evil under-the-lid mat

It all required a detailed cleaning, which I did mostly with WD40 on the metal, household spray cleanser on the plastic, all with a combination of a few old toothbrushes and lots of cotton swabs for tools. The heads of some of those steel fasteners on top of the aluminum boxes were severely pitted with rust and they've now benefited from the same cleaning technique I used on the lid fasteners. I'm not about to open up the electrical covers anytime soon, of course, but I don't want it to be an unexpected chore for the technician, if and when that has to happen someday.







Then, just yesterday, I finally popped the rear passenger bench seat for the first time. No unpleasant surprises this time . . . clean as a whistle. That electric tire pump hidden under there is cool! I extracted that and the expired bottle of tire flat sealing goop from underneath there, with the former now living in my tool box and the latter resigned to the trash bin. What I noticed, though, was the wingnut bolts holding that metal cover in place are identical to the motor lid ones. But these wingnut bolts are essentially brand new, without a speck of rust on them. So, today, I swapped out the hex head cap screws for the wingnuts, with the latter now holding the motor lid in place (nice to be able to quickly show people what's under there without having to use a 9mm socket wrench.) Again. grease on the threads and a small dab underside on the flange.

Next, I went to a local auto detailing shop today to investigate the possibilities of steam cleaning the underside of the car, with the goal of stopping any road salt debris I can't see from continuing to do any damage and to generally give it a good first-ever underside road muck cleaning. There's some surface rust buildup on some of the rear suspension components but not anything all that bad on it or the surrounding sheet metal.





I grew up in Pennsylvania, working on cars in my teens, and have witnessed what horrendous salt-induced road cancer looks like. The $65 estimate I got for the steam cleaning is reasonable and I'm going to take it back in sometime next week. I know that this is the first fully electric car they've encountered and I'll want to be there to point out to them the major high voltage connections going to the battery. Now that the car is living in deepest, hottest, driest Arizona, it will never have to encounter road salt of snow ever again, so I'm guessing that upcoming steam cleaning will keep it in good shape for many years to come.

Nice write up. Illinois must use a lot more salt than PA does. I got some rust (including those bolts holding the motor cover) on my cars (Koorz is worse being a Michigan car), but I haven't had any trouble with the sound baffling on the bottom of the motor lid. Everything under it is covered in road grime, but it wipes clean with a damp paper towel.

I use a pair of Linesman's pliers to break the bolts free.

I would continue to stress that any I-MiEV owner who drives in the winter (salt) season heed what others and myself have said on this thread. In the Spring, it is very important that the underside of the car be flushed off with hose and soapy water. If you use a high pressure sprayer, just keep the nozzle a little farther away when near any electrical connectors. It shouldn't be of any concern if the connectors are sealed properly, but better safe then sorry. It is also very important that the plastic battery shield be removed during the cleaning. It's really simple to remove but be aware that there are a couple of grounding screws that need to be removed (under plastic covers) before dropping either half of the shield. The screen that is attached to the shield along with the battery case needs a through cleaning. The only caution is spraying up the sides of the case to try to dislodge crud from the top of the case. About 3/4 of the way back on the battery case top is a vent for the case. You don't want water in that, however if you take it easy with a hose and be careful in this area, it will be OK. Also, the entire motor compartment needs to be cleaned. This also applies to vehicles in non salt areas as road dirt really packs in there. Other than direct spray on connectors, you should be careful around the vacuum pump as there is an opening (exhaust) in the pump that shouldn't see water. After cleaning with soap and water, I use a product called salt-away that can be purchased from marine dealers. They have a little kit that allows it to be mixed with water while rinsing after cleaning. The product help neturalize the effects of the salt. Although it attracts dirt, the motor compartment should be sprayed with a corrosion inhibiter like "corrosion block" or "corrosion X". Both products protect aluminum parts from corrosion and are available at marine and aircraft suppliers. If you want something a little heavier, "Boeshield T-9" works in a similar manner but also is good on metal parts. This is a Boeing aircraft product and is available at aircraft suppliers and sporting goods stores. I've gone over this before but sometimes people don't read an entire thread. The I-MiEV is a great little car but because of the way it is designed, it has a lot of small metal and big aluminum parts that are exposed to really bad things in the Winter.

As I alway do, I'll be using salt-away.

Brian

Illinois must use a lot more salt than PA does. I got some rust (including those bolts holding the motor cover) on my cars (Koorz is worse being a Michigan car), but I haven't had any trouble with the sound baffling on the bottom of the motor lid. Everything under it is covered in road grime, but it wipes clean with a damp paper towel.

I use a pair of Linesman's pliers to break the bolts free.

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I sure hope Pennsylvania has cut down on the winter road salt. I owned a '64 VW back in the late '70s, while living there, that was basically missing the entire floor pan on the passenger side. I ended up replacing that whole area with layers of fiberglass cloth and molding it in with a long fiber fiberglass filler paste called Tiger Hair.

Linesman pliers were an option for freeing the wingnut/Phillips bolts on the i-MiEV motor lid cover and that was but one tool I used on troublesome fastener number 4. But I didn't want to mar up the wing part at first. The best tool was the 1 1/8" socket, 1/2" drive and with a long breaker bar. You have to grip the socket to prevent it from wiggling around, keeping everything perpendicular while applying pressure to the breaker handle. But, when done with care, it snugs over the edges of the wings and doesn't chew into them. That technique only fails when the wing starts spinning on the shaft of the rest of the bolt. Then, there's little choice other than to destroy the top of the fastener in order to extract it cleanly.

What's surprising was that, despite all the trouble I had with the lid fasteners, the amount of rust on the underside of the flange was minimal. But, yeah, if you're in a wet climate, checking on that mat on the underside of the lid is prudent. It could be no trouble for some but a real mess for others.

Good tips here regarding products like Salt Away, Loctite Extend and Corrosion X. The caveat regarding the metalwork around the back of the battery is noted and will be passed onto the guy who steam cleans my car.

The PA Turnpike stays totally white until mid-April. Every year they seem to run out in my area for the regular roads. I try to wash the car at least once during the winter. The local automatic car wash has a floor sprayer that does pretty good at getting the undercarriage.

Can't wait for Solar Roadways and their pothole-free, heated surface (and hopefully in-road power transfer to EVs) .