Advice to Stop Rust (Especially During Winter)

NWOIHTS

Hi Guys

I just thought i'd post some tips on retaining your car's bodywork integrity throughout the Winter months, how to keep the rust at bay etc. I am an ex mechanic, car restorer for 20 yrs and so have plenty of knowledge and experience of all motoring issues that you can ask.

This is important because it is quite easy to retain your car bodywork and minimise rust, it will look better for a start, retain it's value better and last longer too.

Firstly watch out for the gritters coming out this is when you really need to spring into action. Grit is by far and away the biggest source or rust on most cars and it is basically the worst thing you can apply to a car's bodywork if you don't want it to rust.

If at all possible run a hose from your house to your driveway and after the end of your daily drive on gritted roads, give the car a full hose down and particularly under the arches and under the floors.

Under your wheelarches make sure there is no clogged up dirt, which there almost certainly will be on a car 2+ years old, under the rim, gentle rub your finger tips (wear gloves and watch for sharpish edges) under the rim from back to bottom of arch near back door.

Best to do it when it's dry as the dirt crumbles into dust and blows away but when wet it cakes up and you will have more difficulty removing it. This is what causes rusting wheelarches in most cases.

Also check for mud behind bumpers where it bolts to the body and up behind petrol filler pipes, if it's journey takes it above the wheel in the wheelarch.

If you get a dry relatively warm Winter day get a lying mat and a head torch, and get under the car and look for rust. Generally closer to the wheels and closer to the outside of the car there'll be more likelyhood of rust. If you see a swelling on factory underseal then give it a bit of pressure with the flat blade and see if it breaks open to reveal tin rot. Generally surface rust on flat chassis surfaces away from stress points is usually not much to worry about but best treat it anyway before it becomes more ominous.

Remove loose rust and underseal, chip away with the end of screwdriver (wear goggles and ear protectors cause banging sound under a car can give you temporary tinnitus - trust me I know ) treat with a rust eater, and then spray with underseal.

Check round spring seats on chassis and wheel well for corrosion as it can hide good in there.
Check back of sill - the bit facing towards ground and inside the wheelarch just above the sill as this is a favorite rust spot on most cars. You will usually see a rubber grommet in there, this is for access to apply rust inhibitor when car is being made - make sure this isn't missing or loose or you will be getting water into the sills - not good.
Check extremities of chassis legs usually round towing hooks and such this is a favourite rust trap too.
Check kick plate directly behind front wheel, preferably with wheel off, and check up underneath the spring housing where rust can start round joins. You might find there is a big plastic wheelarch liner and you can't see anything. These can be a bit of pig to remove so I wouldn't bother unless you suspect something or the car is say 8 years old or more.
Generally the spring housings are not as bad these days but used to get really bad problems with some models years ago (before plastic shields were used) where the whole inner wing rusted/collapsed and broke inwards and the wheels bent inwards at the top.

Another tip is do not scrape rust off unless you are going to treat it that day. People do a quick blast round the car scrape the rusty bits, apply rust treatment then leave undersealing/touch up for another day - result rust starts up again.

That's all for now folks and remember keep your car grit and rust free during the winter.

Andrew

TrickyWicky

I have a car thats been sat on the drive for 3 years (engine issues) and have noticed that the chassis is starting to rust just forward of the engine.

Any tips?

gilbert_and_sullivan

Brilliant write up Andrew, agree with every word, and i look after my cars in such ways too, probably why my 16 year old MB is in as good condition as most 5 year old cars, though i tend to pre winterise my cars before the first salt goes down.

However the majority of drivers can barely bring themselves to wash the topside, instead being unable to support their own weight leaning their fat carcasses on the fence whilst the hand wash blokes do it for them, so theres almost no hope of most of them bending down to see if theres any tread left on the tyres let alone actually hosing some of the accumulated salt out from the nooks and crannies....trouble is most people have too much money, or rather access to easy credit and a strange desire to spend their lives in debt, so no need to maintain their existing cars for a long life.

Couple of bits to add....keep those brake pipes greased and or waxoyled, and keep the working parts of the braking system free from crud and lubricated with the appropriate greases, and keep coil springs clean especially the bottom coils where they rust and usually break, again waxoyl is the stuff...nah don't worry they'll ignore that too.

When the salt has finally gone make sure to fully clean the underside, preferably after a few days of wet road driving to loosen the crud, and then inspect and touch up, coat, fix as necessary...caked on salt is the fastest way to destroy cars that i know of.

On the subject of rust preventers, i make good use of Waxoyl and as far as i'm concerned even if its not the best stuff available its a better covering for the exposed bits than nothing or salty water which is what most cars get from day one.

What do you use as someone who obviously takes time over keeping his cars up to scratch?

Regards.

mkirkby

TrickyWicky wrote: »

I have a car thats been sat on the drive for 3 years (engine issues) and have noticed that the chassis is starting to rust just forward of the engine.

Any tips?

Vactan, POR15 (nasty stuff to use but sets like concrete), Rustoleum, Bilthammer products...

All recommended and better than the old school jenolite etc.

Robisere

NWOIHTS - from an ex-workshop foreman, well retired, that is all great advice.

However, I suspect for most people it will be just too much trouble.

Have to add a little tale about rustproofing and commecial products.
Some years ago (70's) I bought the last in a long line of Capri's. It was a GTXL 1600, a write-off, bought as Salvage (NW you know how that goes - or used to!) which I rebuilt as my own and ran for 2 years. According to the Service History, it had been rust proofed from almost new by its first owner. The RP product was called "Cadulac" and is no longer produced, here is why: I attended a relative's funeral on a very wet day and was informed by a rear passenger that her feet were wet. Inspected it back home, taking up the carpets, and was gobsmacked to find that it was cracked from side to side across the rear floor 'drain holes' (put there at manufacture and sealed by rubber grommets.)

I eventually worked out that the rust proofing was to blame. It was totally inflexible, had aged to set like concrete. Very fine cracks had appeared in the stuff, which was like bitumen. Water had entered through the cracks, could not get out, and just sat ther rusting away. Eventually I got some money back before 'Cadulac' went bust, but it was a salutary lesson. If I could get caught like that, what chance for the ordinary motorist?

So now I always recommend a flexible agent such as "Waxoyl" which is great, I used to steam clean and completely dry off the underside of every car I bought (mostly salvage projects) before giving it at least two coats. I know that two vehicles I had which were treated like that, both Cortinas, are still going strong. One has a rebuilt engine, but neither has more than slight surface corrosion, easily rectified.

forgotmyname

Great advice if it was 1970 again..

But these days if you dont want a rusty car yet dont want to go to all that bother,

Just dont buy a Mercedes

Dont see many rusty cars these days, But the time they get a bot of rust the mechanical bits will cost way more to repair than the bodywork.

Wonder if i can fit a 2L Pinto into my MK3 Mondeo, Or a MK4 for that matter? Carb and points.. Oh yeah

Enough room for a rover V8 engine??

atrixblue.-MFR-.

and ofcourse if your going to be "Spraying" underseal, cover up wheel arches and any coloured paint work i.e sills, bumpers, alloy wheels.

when that stuff gets on body work its a pig to get off, dont do it next to your neighbours car either if you dont fancy the hard work of trying to get it off it.

red_eye

spray waxol under the car on every chassis orifice and in the drain holes on the doors and boot, when washing wash the crap from the wheel arch lip (especially if you have a mk5/6 escort)

Lum

If you're lazy like me, do the check underneath for rust while you're getting your tyres, or some other work, done and it's up on a lift

1886

TrickyWicky wrote: »

I have a car thats been sat on the drive for 3 years (engine issues) and have noticed that the chassis is starting to rust just forward of the engine.

Any tips?

Why not just get rid of it instead of kidding yourself you're going to fix it. Three years is a long time, you would have done it by now if you were going to

NWOIHTS

Waxoyling is only worthwhile if the car is practically new, > 1 year old, and if done on an older car with rust starting inside panels it will just make it worse as it will hold moisture in the rust.

What I find in one of the most common and first noticeable rust spots on a car is rear wheel arches and the rust usually creeps out from inside the panel where the inner wheel well is joined to the outer panel. The boot is generally a water trap as condensation from rear window runs into boot as well as it generally being where all the moisture from the interior ends up, and stays, moisture condenses on all the bare metal panels as the warm air from the interior meets the cold panel.

It's a good idea to open the boot and remove carpeting - both floor and side panels - on a dry windy day to let it air.