Rustproofing

[snes]

Hi!
I've had a quick spray around the box sections of my GTL with Bilt Hamber wax. I used the Waxoyl hand sprayer thingy with lance attachment - not wonderful, but I couldnt find an affordable alternative. Can you hire this sort of equipment?

Anyway, I could access all the floorpan and rear box sections, chassis legs etc. but when it came to the front........ Are there any access holes where one can insert a probe or are they not true box sections? I dont want to start drilling holes for obvious reasons.

Needless to say, I'm sure the job would be a breeze with the chassis off. But in the real world.....

Any thoughts or ideas?

 

[Azazello]

I am interested in this matter, too!
I was planning to spray my box sections with dinitrol 3125, and I was wondering if 500 mm tube was sufficient to reach all sections, where could I access various places and if I need to drill holes, how much wax do I need in order to do all the job...
Any info or advice is welcome...

 

[Cornish4]

Hi Azazello, didn't one of our members suggest removing the body mounting bolts one at a time, so accessing the chassis along the length of the car. Also drilling a few holes in sensible places isn't such a silly idea, and they only have to be just big enough for the probe to enter, say 5mm. I reckon 2 litres of fluid should be more than enough for the job, but if you by a 5 litre can you will have some spare for future use as this treatment needs repeating now and then especially if you use your car a lot. Regards Brian.

 

[barnfind]

The waxoil standard sprayer is very poor, especially with the waxoil itself which tends to be too thick and doesn't atomise very well. You can hire the proper gear from some tool hire places, but at a cost. If you have a small compressor then a Schutz gun is a good buy and usually comes with a probe and you can buy the fluid in a canister to suit.
Both the Bilt Hamber and the 3125 are very good and can also come in an aerosol with a long probe. This is a reasonably good substitute in my view and gives a good even fan type spray at the end of the extension probe (that can be bought as an extra for Dinitrol products for just a couple of pounds, or, I thnk, comes as standard with the Bilt Hamber sprays).
The outer box section innards can be accessed by taking out a seat belt bolt, and by taking out odd mounting bolts from along the tops of the cills. The aerosol probe should fit in those okay (7mm hole, bigger for seatbelt mounting.) Front chassis members under the engine need doing as well ideally, you may get some access through the bolt holes for the bumper brackets, if you remove them.
It is worth doing the floorpan and wheelarches with 3125 as well, letting it dry and then putting one of the thicker anti abrasive grades on afterwards. The thinner stuff primes the surface, soaks into any surface rust and creeps into seams. The thicker overlayer then beefs that up.

 

[Azazello]

I was thinking of this:
http://www.ebay.it/itm/3-x-DINITROL..._Body_Shop_Supplies_Paint&hash=item33748b5259

But it says ML3125 while ML and 3125 are different products, and the image shows the ML can... It's worth a question.
Quite expensive delivery, I shall ask for cumulated shipping with other italian friends and for a nearer seller, too... But I do not think I have a chance to find it in Italy.

I am using my r4 quite often, since it is the only car I have. Not every day since I use public bus to go to work, and it sleeps in garage as well, but an average of 10.000 km per year is normal for me.

Thank you for the holes description, very useful!

 

[barnfind]

My understanding was that ML was for preventing rust on clean surfaces, such as new or nearly new cars or repaired sections of nearly new cars.
3125 is generally marketed as something to treat older cars and contains a rust inhibitor, being suitable for spraying onto areas that have surface rust already present.

 

[Cornish4]

I can recommend the Bilt Hamber product, S-50 I think it's called, it's in aerosol cans, and it does indeed come with a very useful plastic probe 50cms long.

 

[alewis]

very interesting discussion. I am currently rebuilding the chassis of my 1971 van and want to do all I an to stop the rust given how easy it is to access everything with the body off.

A massive rust nasty i have found but doesnt normally get mentioned is where the front bulkhead meets the chassis. On the van rain has got into here and rusted the 2 front triangles out from the inside and done some nasty damage to the front structural members running forward.

I only mention this as I feel this area can be easily missed and the rust only appears when its really bad / almost terminal !


Some of the damage can be see in this thread.
http://www.renault4.co.uk/forum/showthread.php?t=5112&page=2

 

[politeperson]

Waxoyle is great, but I dont see how you can apply it without leaving it in hot water for a least 20 minutes pr litre and spraying with a shutz gun at 100psi. This creates a cloud of waxoyle under pressure which blasts along the inner box sections coating everything beautifully.

I do not see how you could get any decent pressure by hand pumping, especially if the waxoyle was at room temp or below.

Even with a decent compressor and a bare chassis on trestles, the last one I did with a 500mm probe took me a couple of hours at 100 psi and 10 litres of heated wax. I had to drill some holes to get there, the bit you miss will definitley rust through, and any foam must be removed.

Well worth it though..

 

[alewis]

Definitely agree, I've used a shutz gun for applying waxoyl in the past and its amazing, only downside is it ends up full of waxoyl !

 

[barnfind]

The triangular void can be accessed by drilling from within the car, through the toeboard. You can then seal the hole(s) with a rubber plug afterwards.
It is a fact, apparently, that if you do miss a section of an enclosed area, the corrosive effort is concentrated there. I am not asure why this should be, but no doubt the chemists amongst us may be able to advise.
There is also the issue of that dastardly foam fill that Renault used in later models. That needs raking out, if it hasn't already rotted the box section. It is also a fire and fume hazard if you are welding near it.
The old advice given with Waxoyl in the seventies, was to tape up all of the drain holes in your cills, pour in a litre or so, and then go for a drive. This would swill it around inside the section and flood everything. However, I suspect that waxoyl has changed its constituency since then, the original stuff that I remember spraying my '66 Amazon with was much thinner and used to have the beneficial side effect of creeping under and softening up old underseal. The current stuff needs heating or thinning or both, to become properly liquid and I can't imagine it creeping anywhere!

 

[barnfind]

very interesting discussion. I am currently rebuilding the chassis of my 1971 van and want to do all I an to stop the rust given how easy it is to access everything with the body off.

A massive rust nasty i have found but doesnt normally get mentioned is where the front bulkhead meets the chassis. On the van rain has got into here and rusted the 2 front triangles out from the inside and done some nasty damage to the front structural members running forward.

I only mention this as I feel this area can be easily missed and the rust only appears when its really bad / almost terminal !


Some of the damage can be see in this thread.
http://www.renault4.co.uk/forum/showthread.php?t=5112&page=2

That looks pretty much like mine did. The problem with mine was that it had been overplated two or three times by the local garage, leaving a club sandwich of rusty metal that just got wet every time the car went out in the rain and carried on corroding without ever drying out properly. The rear outriggers were rotted mainly as a result of the foam fill trapping moisture.
Internally, from the staining, the car appeared to have had wet floors, probably as a result of a blocked up drain from the heater box. It had lived in a farm outbuilding with relatively light use, but the underfelt below the mats was probably perpetually wet underneath. By the time we found it, of course, everything was bone dry, having not been used for decades.

 

[edhothersall]

How about rustproofing door inners and bottom, any tips?

 

[Cornish4]

Hi Ed, if you remove the door pockets and unclip the trim panels you can access the inside of the doors. If you are lucky and don't find any rust simply make sure the drain holes are clear, and then just spray the inside with your chosen cavity wax. Be prepared for the doors to drip wax for a while, and don't overdo the treatment like I did. Every time Marigold is parked in direct sunlight she leaves a small puddle or two of oil. Plus it runs down the sills and upsets the better half when it gets on her best jeans!:eek: Brian.

 

[ade]

trouble with Waxoyl, even if put in hot, it cools down as it progresses along the cold metal surfaces, then it congeals and potentially forms a dam just at the entrance to seams. I use something thin, like Supertrol or 3125 heated applied using an electric airless sprayer (e.g. Eagle ,very cheap £50) as i don't have a compressor.
The reason why water gets into the triangular section is because theres no bolts bolting the body to the chassis along that 400mm just behind the wheel, and, on the n/s the exhaust dries everything out, causing even more gaps. I put bolts along there.
Don't also forget to treat, A,B,C and D (beside tailgate)-posts, tailgate itself, bonnet cavities etc etc ....ade

 

[alewis]

Ive welded the top seam up in an attempt to stop it happening again.

 

[Azazello]

I can recommend the Bilt Hamber product, S-50 I think it's called, it's in aerosol cans, and it does indeed come with a very useful plastic probe 50cms long.

With aerosol can do you mean something similar to rattle cans, so I do not need a compressor?
I found the product on the net and it is a bit more expensive than dinitrol (above all the delivery to Italy); do you think it is better than dinitrol so it's worth paying more or it's just the only product you have direct experience with?

 

[politeperson]

The reason why car sills rot is not usually because of water ingress or blocked drainage holes, it is because of the condensate formed in a closed steel section once every 24 hrs because of the temperature difference between night and day and the effect this has on airs ability to hold onto water content.

It really doesn't matter if a box section is totally sealed from water, the inside will become wet as water is formed through condensation. This will then settle on top of a seam which eventually will blow through with rust.

This is why it is essential to use enough pressure to form a heated wax mist through the correct nozzle so that all the internal surfaces are coated. Believe me at 100psi there is a positive hurricane going on in the box section and the wax mist forces the stuff every where.

The fact the wax returns to a solid at "normal human" temperatures is essential, otherwise, over time the wax would run out the bottom and leave the panel unprotected.

A bare metal, waxed, mild steel panel can be left outside for years and years. It will never rust because the clingy wax prevents air or moisture getting to it.

Also, engine oil is no good for protection for the same reason and also the smell you would get inside the car and the fact you would be dripping oil every where!

Second hand engine oil is even worse as it contains acidic products of combustion and carcinogenic materials.

So really, the only way to do it is with the proper stuff I would say

 

[Azazello]

So really, the only way to do it is with the proper stuff I would say

So, good wax to apply with a good compressor?
No aerosol cans because they have not enough pression?

Your text sounds good to me, good explanations...