Undersealing - a concensus ?

Just been trawling through the multitude of 'undersealing' threads - or should I say arguments and yet seem to have found no concensus as to which is the better method or material.

I have got to be honest in my past I have both Waxoyled and oil sprayed. The Waxoyl a nasty horrid job and a bastid to get off the driveway, oil not exactly environmentally responsible but easy to spray a good use for old oil and not as much hassle as Waxoyl and landrovers put oil on the drive anyhow. Environmentalists needn't respond re oil spraying - I don't care - just so you know.

Just about the only tool I have never got right in my tool arsenal is cavity injection stuff but I have yet to find any 'decent' stuff such as lances and hoses that don't clog yet.

Now given that I am these days not really a fan of grovelling around on the floor and getting covered in crap should I even bother buying tools or just pay somebody else to get dirty - the downside to this being the quality of the work, expense, the upside being almost zero hassle and no time in the shower necessary.

If I invest in the toolkit are there any people here with decent kit that can recommend what and where from - not the cheap junk with a 300mm piece of tube. (I have two commercial high pressure / volume compressors)

If anyone knows of a decent trader to do the work in the North West Manchester / Sheffield sort of area drop me a line - I have already spoken to a couple but I'm not paying £600 for 8 hours work.

have bin thinking of doing this myself with the waxoyle kit you can buy from halfords is it really that good and how often should it be done

Waxoyl done right every couple of years but be prepared it is a nasty nasty job - very hard to spray properly even heated since it can cool and clog pipes for fun if the temperature isn't right outside, it is OK on large easy to get at surfaces but getting it into cavities successfully is something I have never really got right. What they don't tell you about Shutz guns and the like is that they only work properly upright so you need to get the car VERY high to be able to use it 'on the tin' as designed - horrid job for the DIY'er really.

Oil spraying I'd do once a year, thinned it down with a bit of diesel (not too much) and used a normal 'siphon' pot paintgun with a 2.5mm nozzle/needle combo.

ive used a b and q garden sprayer before works well but still need to thin it a bit !

bitumen paint

Dr_evil said:

bitumen paint

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never mind fekkin underseal you need to be concentrating finishing yer homework so yer can ave a go at that v8 tratter that wont start

johnny curt 1 said:

never mind fekkin underseal you need to be concentrating finishing yer homework so yer can ave a go at that v8 tratter that wont start

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I've done my homework ………ish got a few electrical equations left to do


I'll be attempting it this weekend weather permitting although it looks like snow up here

I have avoided hard coatings such as the bitumen paint for a long time now. If water gets behind it then significant damage is done before it is visible. One thing that I have done is clamp a sacrificial anode to the rear cross member (get them from most boat chandlers) this should in theory halt the rusting process to a degree -the reasons are somewhat complex but it is the same issue that causes destruction of aluminium engines and radiators when bad earths and inappropriate coolant / antifreeze is used.

Google galvanic corrosion if interested in the process ...

My mate had his cosworth painted in bitumen, good half inch coat and it never rotted thats the key……****loads

i had a mk 4 cortina once over with a near mint undercarriage due to the previous owner coating it evry year with the used drippin out of the chip pan evry time it was cleaned out it looked like hed been trowelling it on uke:

Right now it is looking like a few dirty weekends with Dinitrol 3125 ... really not a job I like or even want to do but praying to the rust god is mandatory with landrovers. Based on what I can see on my Disco 2 they didn't bother there ass protecting the chassis with anything internal or otherwise - would have expected better for a 2004 car.

There are few jobs I truly detest, gardening is one -- rustproofing cars is another -- my 15 year old Landcruiser chassis was in much better condition

Rustproofing. Get under body steam cleaned properly. There are places that do this, ask at your local bus garage. Get underneath and remove/clean up any surface rust and apply a good rust convertor.
Paint everything you can paint with either POR15 or if you can get your hands on it,Kephos 253. (This is what Aston Martin Heritage protect all their restorations with.)
Coat everything with a wax type coating, preferably dinitrol or eastwood, or even better, Tectane. Waxoyl is not as mobile as these products in our climate. Especially when your warmed up waxoyl is sprayed onto nice cold steel. it doesn't penetrate as well.
Galvafroid Is another product that comes very highly recommended, It's used for protecting steel boat hulls though I have never used this personally so can't vouch for it.

Ok fellas possible stupid question so be warned. How to you get the underside of your LR clean enough to waxoyl? I steam cleaned mine the other day and while it was in the wash bay it looked quite clean, only when I sent it up on a ramp (rare chance I get to use a ramp in work) I noticed that it wasn't really clean at all, defo not clean enough to wayoyl onto anyway! Is it just a case of getting on you back with a wire brush?

Never mind dan read my mind.

Doesn't need to be sparkling, just free of as much surface rust as possible, good to give the inside rails a good blast with an air gun too and take off front bumper to try and force crap out

Can also spray chassis with rust killer or rust to metal stuff first before applying wax

Where I used to work we used to have an outdoor ramp and an apprentice. That worked well,

Getting a car like a landrover high is the bain of life since I am not in the motor trade any more - not for some time - and it is the only way to do a thorough job. When we cleaned truck's and other plant we'd wear what was almost a wetsuit, put the vehicle on 8ft high ramp / deck and blast away guessing many places don't any more. Friend of mine who has a garage says he can't anymore without installing special sumps and traps to avoid contamination - absolute BS but the powers the environmental agencies have is scary ****.

I love the idea of the likes of phosphating with Kephos, if I ever did a body off with the landrover I'd give it a go but that stuff is lethal - worse than two pack isocyanates I do have breathing gear but it seems a little impractical for an assembled car and does seem to need some specific pretreatment that I doubt would be successful on yer driveway unless of course you do 30cm sections but then how can you do that inside boxes so dipping becomes necessary - too much hassle and cheaper to buy a galvanised chassis.

As for the POR-15 I used that once and it is what I'd call a high maintenance coating, if it gets damaged you really need to fix ASAP because water gets behind it and destroys from behind - bit like powder coating, plus if you don't get it dead right it peels off in sheets - POR-15 is a three step task too - cleaner, primer, POR-15 ...

I just want to put a serious brake on any further degeneration, I'm not crazy enough to think I can stop it but you have to try eh ..

You think a decent rust convertor followed by say Dinitrol or Tectane would be a good combo - never heard of Tectane until now, never heard of Galvafroid either - I'll do some digging.

I've heard of chassis box section being filled with expanding foam, it actually helps if the box section is damp inside. Given that a high density foam expands to 40 times its size it would build up a fair old pressure. The downside being that once its in there, thats it for the life of the chassis. Never tried it myself but interesting nonetheless.

You know if you could get the box completely dry inside - maybe get it all ventilated with air at 100 degrees or so for a couple of hours, foam it, that may not be such a bad idea to preserve an old and fading chassis, not sure how you could be sure to get in all the corners but perhaps drill holes in the corners and fill a bit from each kind of thing - the downside is as you say it is for life and you woulnd't be doing any welding with that stuff in there.

old engine oil, mixed with diesel, touch of grease waxoil etc, heat up, spray with a shultz gun, my mx5 and xr31 all done like that, last 20 years, never ever rusted, done every year, just doing the gaylander now.