Best Underseal for an older van ?

CrappyVanButFun

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Hi as got an older van showing some rust here and there underneath and would be interested in thoughts on undersealing etc.

Had it sugggested actual underseal can throw the rust back the other way and that thick oil or grease is a better bet.

Anyone have experiance of how things go please.

I`m leaning towards a thickish grease underneath myself, then each spring a clean off and re application where its shifted.

Thanks Mark.
 
CrappyVanButFun said:
Hi as got an older van showing some rust here and there underneath and would be interested in thoughts on undersealing etc.

.
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Many of the car forums have this kind of advice and certainly Waxoyl type products can be used. I remember reading to be very careful of products that cure and then could split leaving and area underneath the new sealant that can trap water; likewise product that hold dirt / road salt because they are sticky can also be dangerous. Also Amsoil seems very highly rated.
 
"Waxoyl" not only rust proofs it also cures existing rust, we tested it when I was at work. You need a nice warm day to apply it to a vehicle so's it liquifys or keep the container in warm water.
 
Dinitrol 4941 Underbody Sealant is really good stuff, better than Waxoyl in my experience

"Dinitrol 4941 is Thixotropic.
It will harden on the surface, but remains elastic underneath, and if scratched or chipped will heal by creeping back across the gap."
 
I use Waxoyl on my older van but this time of year it can be hard to apply. I usually thin it down a little with some used vegetable oil and spray it with a pump type garden sprayer, with the internal filter removed to make it easier. Even when thinning down it would still need to be carefully warmed up just to get the waxoyl flowing as it tends to solidify quite quickly in the cold weather.
This is my budget method, but, if money were no object I would opt for the Dinitrol treatment.
 
I've wasted some money on having vehicles waxoiled 7 up to present and 6 of them I've changed shortly after, whoever finished up with them had a good buy. The 7th was our present new motorhome in 2011 but we intend to keep this one as our last.

John.
 
artheytrate said:
I've wasted some money on having vehicles waxoiled 7 up to present and 6 of them I've changed shortly after, whoever finished up with them had a good buy. The 7th was our present new motorhome in 2011 but we intend to keep this one as our last.

John.
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a good cleaning with a wire brush and a couple off coats hammerite is as good anything on rusty metal. bazzzzz
 
Waxoyl can be sprayed inside body members and panels where you can't get in with anything else to clean off existing rust. It's the rust you can't see which is the problem, Waxoyl's rust CURING properties are it's biggest plus, if you spray it on rust it coats it, turns the rust black, and stops the corrosion continuing. Putting underseal on where you can access easily is a waste of time. The downside is, Waxoyl has to be warm enough to give it a paraffin like liquidity so's it can be sprayed, ideally on a really hot day, otherwise it clogs the spray tubes before it reaches where it needs to go and doesn't soak into the existing rust. I'm assuming the professionals who apply Waxoyl must have some means of keeping everything warm. We used to spray Waxoyl into the steel members of our boat trailers, which were already corroded due to sea water getting inside, we never had a problem after the Waxoyl treatment.

http://www.waxoylprofessional.com/Waxoyl-Professional.html?gclid=CJ_0--2xl7YCFUnMtAodjT4AGg

http://www.youtube.com/watch?v=zcNP4INYEMI
 
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I have found Waxoyl to be pretty useless and I speak from experience after working on classic cars for many years. Waxoyl tends to wash off with water which is no good especially on exposed panels.

We ended up using Dunlop Panel Guard which was obtained from Brown Bros. the motor factors, it was a viscous, oily, tarry goo which once it got on to something was very hard to get off, can't say that about Waxoyl, if you get some on the hands, it simply washes off.

I have just been out to the workshop where there are still some tins of Panel Guard, but unfortunately they do not state the contents. I am not sure whether they are still available & I don't know if Brown Bros are still around.

I have to do the underside of my van this year, have not got enough Panel Guard & will have to look for something else but it won't be Waxoyl.
 
Waxoyl is good for spraying inside the body members and panels, and it does kill rust not just cover it up. On exposed under parts, providing existing rust is removed, any rubberized underseal will do, if the rust isn't removed it's a waste of time.

40 years ago we conducted an experiment, we took two steel panels which had equal amounts of corrosion on each, one we sprayed with Waxoyl the other we left untreated. The panels were left exposed to the elements, significantly to salt water spray, two years later the Waxoyl treated panels corrosion had been contained but the corrosion on the untreated panel massively increased. Although the panels had been rained on, snowed on, hailed on and blasted with sea water.....it hadn't washed off.
 
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This is very interesting, It's good to hear different experiences.
Does anybody remember, or still use, the old diesel and used engine oil concoction?

'Twas a messy affair and best done wearing oilskins with the hood up, whilst working in a garage pit or under ramps.
It stuck on alright, but I'm pretty sure it was harmful to rubbers and cables ( plus any living creatures that got near it).

Then we moved on to some other tarry black stuff ( forgotten the name now) that I often used to paint on the external walls of cellars and basements ( after excavation). Goodness knows whether it stopped the ingress of damp, but it certainly would stick to your skin if it made contact. The skin would have to wear or tear before you'd be free of it. This could take weeks!

For interest's sake, I looked yesterday at the butts of an old wooden gazebo thing we built about twenty five years ago. The 4x4" posts were painted with this black stuff at the bottoms and up to four inches above ground level.
The posts seemed to be in reasonable condition, but the black, where visible, had weathered to a thin grey and had lost it's rubberyness.
I don't suppose anything lasts forever, and I wish I could remember what it was called. It was some horrible stuff a bit like shoe polish in texture.

sean rua.
 
Possibly an odd suggestion but what about something like ACF50?

I use it on my motorbikes and it's very good stuff. It was developed for the military (US navy jets/helicopters IIRC), the ACF standing for Anti Corrosion Formula.

The downside is that in-reality you'll probably want to be applying it maybe twice a year.

As I say, I use it on my bikes as the header pipes always suffer badly from de-icing salt and its very good stuff.

Just a suggestion
 
Anti Rusting

My dad used to use old engine oil painted all over the underneath with a brush. It as to be done every year as it does get a pasting off the weather but it is free after every oil change. I still use this method and I am 72 next month, but I am not sure if the newer synthetic oils are as good as the old engine oils. One thing I am sure of is you sure get no rust on the concrete flagged path if you don't cover the drive first before you start doing the job.
Tom ....
 
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