My 9 year old Ford Ka has just passed it's MOT with one advisory:
"Bubble rust starting on both front floor pans front (sic)"
My gut instinct is to get under it with a wire brush, remove as much as I can, and underseal over it. Would that hold it at bay at all or is it fighting a losing battle?
"Bob" wrote
Certainly it would slow it down, but as Neil Young rightly stated, "Rust Never Sleeps"
Bob explained on 11/08/2007 :
In my experience that would make it more even faster. I would be inclined to wire brush it, then use a rust converter on both sides and finally underseal. Underseal only will trap the moisture and remaining rust in there, making it able to progress without the interruptions of drying out.
Ka's rust pretty terribly for a modern car. I'd flog it TBH because I hate rust.
Wire brush or 80 grit DA, two pack etch primer with phosphoric acid in it, (yes, you can use it without an airfed mask, but I would use a charcoal one), brush it on, bang some rattle can paint over the top, then put your stonechip over the top if you must.
Wot he said. Also check the inside of the chassis member just above the exhaust back box and just in front of it; they go there too. Bitch to weld as well.
Paint it with old engine oil. You'll never get rust under oil, although the process of putting the oil on is a bit messy. Bit it's 100% effective. Don't remove any material first. The more dirt and stuff the better as it helps to hold the oil like a blanket.
Rob Graham
How long until it comes off? I wouldn't bother putting dinitrol on the bottom of a car, let along engine oil...
Difficult to say. Some months, even some years. If there's plenty of crud there it'll last a heck of a time.
R
================================== Painting or spraying the chassis with oil was standard practice at one time. The underside of Minis in the 1960s were sprayed with light oil as part of the normal service routine, although I'm not sure if this was a universal practice.
It won't cure a rust problem but it will probably stop it getting worse.
Cic.
And look how long they lasted!
Put it this way, the MK2 Golf, one of the first cars that didn't have a big propensity to rust, was primed with fantastic etch primer that stops almost all spread of rust, painted, then heavily undersealed, and injected with a large amount of cavity wax. I suspect what worked for VW and tends to stand up 20 years is better than what didn't really work in the 60s...
I'd ask exactly what "bubble rust" was! Like normal rust, but with bubbles? Do they mean corrosion? If so, why not say so? The MOT manuals are freely available online, so check to see WTF they are talking about :-)
Al.
Advisories are entered by the tester, and are not selected from pre-defined lists like failures.
They can be worded however the tester wants, to provide a reasonable explanation.
If I know Minis (and I own four!) then most of them leak enough engine oil to rustproof the entire underside! Certainly true of my latest car, a 1971 model which had a massive leak and zero (really!) underbody rust.
No, I wouldn't put dinitrol on either. Plus it costs money. But look at any machine e.g. combine harvester, where grease has run out of the bearings and got around the metal plate to which the bearing is fixed. No rust there, however old the machine is. I appreciate that this is grease, not oil. But I have an old Merc which I oil up every two or three years and that's kept the rust (which was already there) off.
R
LOL It didn't do them much good. They all rotted like hell.
=================================== The point is being missed.
Doubts were expressed about whether oil would remain on the underside of a vehicle when it was either sprayed or painted on. I pointed out that it used to be a common practice to do this and the practice (which dated from the 1930s - possibly earlier) continued into the 1960s when it was done on Minis. The fact is that oil does stick reasonably well but needs to be 'topped up' from time to time.
The fact that it didn't do much good for Minis is beside the point because it was a technique being used inappropriately. A treatment that was good for 1930s cars wasn't much good for the 'tin box' style of cars which arrived in the 1960s.
To repeat, spraying or painting oil on to rusted areas won't cure the rust but it's a useful stopgap treatment to prevent rust spreading, particularly in inaccessible nooks and crannies.
Cic.
Motorcycle chain grease aerosol is better than engine oil. It goes on thin and gets in to every nook and cranny then dries off to a thick grease.
But, the advisories cannot be removed from the database!
One of my wrecks, sorry, CARS, has a few advisories on it, and I actually had every one of them done. But ... The ads cannot be removed from "Big Brother". I'm f*cking furious, having spent a LOT of money getting this car PERFECT, only to find that I cannot register that the work has been done.
Why should ads be entered? If they can be entered, they must be able to be removed, especially in my case as I went to a lot of trouble to keep my car perfect.
I think the whole system sucks - My usual mech spends 75% of his time at a PC rather than actually doing any real work.
Words fail me.
Al.
I like the current system mainly *because* you can see the advisories online.
Before I commit to buying a car these days, I'll check the advisories so I can check to see if they've been fixed or not. If not, at least I know what needs looking at before the next MOT and I can adjust my offer accordingly.
Could you have it MOT'd again?
Where do you check the advisories online?
Cheers, Rick
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