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diesel/engine oil as rust prevention - steveo30
anyone try this?? i run a very clean mk2 golf ,and id like to keep it that way..i feel waxoil has limited suceess where a little rust has started in hidden seams etc

seeing as diesel /oil mixture is very thin i recone it would seep into seems and hold back the rust

im only thinking of using it in the sills and inner arches etc.

any comments ??? i do plan to use it over some newspapers before i get told off for that
diesel/engine oil as rust prevention - John Shelton
Why dont you just thin out some waxoil and pump it into the cavities? Its harmless and wont flow into places you dont want it to flow into. It works better than something like oil which will shortly wash out of the cavities when car is used in wet weather eg, wheelarche seams.
diesel/engine oil as rust prevention - THe Growler
In years gone by old sump oil was often used for this purpose before products like Waxoyl were invented. IMO the messiness isn't worth it. Plus it won't last long because it doesn't cling (or bond) with the surface. I waxoyled a 26 year old car which had no trace of rust in 1991 and 10 years later it was as rust free as when I started. And this was in a coastal climate with high salt content and humidity (Bahrain). It's all in the quality of the application process. Of course it costs. Used oil doesn't, but you would have to keep applying it.
diesel/engine oil as rust prevention - Civic8
You would be better off cleaning rust off and re waxing.oil will wear away with salt and enough water.I did years ago try it and found I had to do it again six months later ended up cleaning off rust undercoating and spraying did not have a problem after that.The art is to clear all rust away not cover as it will come back
diesel/engine oil as rust prevention - madf
Dinitrol is better than Waxoil: penetrates better.

Oil - if it comes into contact with rubber - leads to rubber perishing.

Used engine oil is carcinogenic.. I would NOT (NEVER) put on a car due to risk of contact when servicing it


diesel/engine oil as rust prevention - steveo30
im talking about seams and places that are hidden...i have apply both dinitrol and waxoil to cleaned up rust ,and ive found that it didnt do alot...i know its great on new stuff, but im not convinced it stops existing rust getting worse
diesel/engine oil as rust prevention - Dizzy {P}
A scientific study about 30 years ago showed that old engine oil did more harm than good because of the acids it contained and new engine oil was no good eeither because the dust particles it holds provide a passage for dampness and salt.

In my experience, having used Waxoyl since 1975, it is over-rated. It does help slow down rusting in seams but only if it is diluted with about 10% white spirit, then heated until it is translucent and applied to hot bodywork, e.g. on a hot day in mid-summer. Otherwise it just doesn't get down into the seam between the spotwelds and therefore traps in any dampness rather than excluding it.
diesel/engine oil as rust prevention - nick
From experience I agree with madf. Dinitrol 3125 is better than waxoyl as it penetrates much further. Practical Classics did a test a few years back and Dinitrol came out top.
diesel/engine oil as rust prevention - steveo30
ok..i'll leave the oil...does anyone have any links to reviews/tests of rust prevention fluids or paints for that matter??

ive searched but cant much by the way of reviews
diesel/engine oil as rust prevention - dieselhead
yup but having said all that some of the best unrestored classics had there sills/door bottoms etc. filled with engine oil. And you don't find much corrosion on the front subframe of a mini.
diesel/engine oil as rust prevention - Dizzy {P}
yup but having said all that some of the best unrestored classics had there sills/door bottoms etc. filled with engine oil. And you don't find much corrosion on the front subframe of a mini.

I bought a 1965 Triumph 2000 in 1970. The sills on these cars have a centre wall as well as inner and outer walls and by lifting the carpet the centre wall can be seen through holes in the inner wall.

All these sill components were rust-free so I decided to keep them that way by plugging the drain holes and filling with old engine oil. After a couple of weeks I unplugged the drain holes, partly because the oil had soaked through into the carpet!

The car failed the MoT less than two years later because the inner sills had rusted through. When I queried this with a car restorer, he told me about the tests that had been carried out that showed corrosion to be hastened by using old or new engine oil.

Regarding corrosion of Mini front subframes, that's a good point. All I can think is that this may be a different situation because the subframe is in the open air rather than being an enclosed part where dampness persists for months on end. That's only a guess and there may well be other reasons for or against.
diesel/engine oil as rust prevention - nick
Get a copy of Practical Classics and see if any of the back issues available cover this. If not try giving them a ring and they may be able to send you a copy of the tests they have done. IIRC, waxoyl, even if thinned, just sat in top of any existing rust whereas dinitrol 3125 penetrated about 2-3 mm into crusty rust. I had an old Triumph Toledo a few years ago an religiously injected waxoyl everywhere with an airline and a proper applicator. Despite this, the sills still went from inside out. When I cut into them, the rust was covered with a good thickness of waxolyl but it had had little effect. If you car is rust free, then any wax should do some good but once rust has started, dinitrol seems good.
diesel/engine oil as rust prevention - Ppaul
My late uncle used a product called Supertrol. Is this the same stuff as Dinitrol?

I've been considering applying Waxoyl underbody sealant to my '95 primera this summer, but I recall reading/hearing that it wasn't worth the hassle. Is this the case?

diesel/engine oil as rust prevention - madf
My comments on Waxoil vs Dinitrol are based on practical experience.. my own.

We bought in 1980 a 5 year old Mini estate.. 20k miles.. and injected all body sills etc with Waxoil thinned with paraffin. Stank a lot - it was an ideal time to do it - summer.

We kept it for 10 years (!) with meticulous care and attention and the good news was it did not need new rear doors (a favourite rust spot). We had , howver, to put in a new fuel tank.. rust in seams and neck, rear subframe, sills and rear skirt under rear bumper.

So much for Waxoil.

Dinitrol applied to a rusty Ford Fiesta 1993 appears to have stopped rust gaining more of a hold.. son has run and neglected it for 2 1/2 years so far.

Dinitrol is ideal in spray cans for applying to rusty seams where the paint has flaked and penetrates the seam and sticks,

- unlike Waxoil which just sits on top of rust and allows it to fester.

Having used Waxoil for 20 years , I say Dinitrol is much much better.. 1970s technology versus 1950s..


diesel/engine oil as rust prevention - dieselhead
I have owned a few Datsuns 120Y vans etc. in my time so i know a bit about rust.
I think the quality of application is more important than which product you use. The waxoyl spray kits don't atomise the fluid and will always leave areas that don't get coated. This can do more harm than good.
I do know that if a box section is treated, any areas missed become more prone to corrosion than if no treatment had taken place at all. Same applies if you apply rust proofer once the flake type of corrosion has set in.
Best treatment i have found is to spray all the seams and surface rust with something thin like WD40, allow it to soak in then back this up with a coat of wax to keep the water out.

diesel/engine oil as rust prevention - Cliff Pope
I agree oil in the cills is useless. I tried that in 1964 on a brand new Morris 1100. I plugged all the holes, filled the cills to the brim, left it for a day, then drained it out. It created an apalling mess, and the cills rotted through in 5 years.

I have always used Waxoyl, but am impressed by the votes for Dinitrol. Waxoyl as it comes though is useless. It is far too thick to spray properly, and also goes all lumpy and clogs the nozzle. It needs diluting with at least 10% white spirit, and then heating up. A bowl of boiling water helps, but best is to leave it on the hot Rayburn flue overnight.

I have never managed to get the extension pipe with the nail in the end to spray properly. I always drill 1/2" access holes at intervals on top of the cills,poke the ordinary nozzle in, and plug afterwards with special rubber caps. On the Triumph these are hidden by the cill guards anyway.
diesel/engine oil as rust prevention - machika
I've been considering applying Waxoyl underbody sealant to my '95 primera
this summer, but I recall reading/hearing that it wasn't rth the
hassle. Is this the case?

Any car produced in the mid 90s should be well protected underneath, I would have thought.
diesel/engine oil as rust prevention - Mondaywoe
This time last year, when I went to prepare my Mum's 1994 Clio for MOT, I found most of the underside really bad with rust - no perforations, but lots of serious 'scaly' rust. I coated it with a mixture of grease and oil (dash of grease with a paintbrushful of oil rubbed into it.) This produced a coating that 'stuck' OK initially, but I haven't been able to look at it again since. Will be interested to see if it's 'stabilised' any or just got worse! The thing is, it's one of those situations where paint would be too awkward to apply, so it has to be something 'oily' that will creep into all the corners.

My own feeling has been in the past that oil+grease produced a suitably 'sticky' substance. I am, however, well aware of the stories about acid being in the old oil and possible carcinogens. (No, I'm afraid I don't wear gloves..!)

diesel/engine oil as rust prevention - sierraman
I agree,I,ve hacked off many an old sill and found evidence of Waxoyl,it does not flow evenly,sticks in big lumps instead of flowing into the nooks and crannies.The decidedly low tech applicator does not help.I spray the underside of my car using a paraffin gun loaded with a light oil.Yes,it has washed off by the end of the winter but it only takes half an hour to do.
diesel/engine oil as rust prevention - 3500S
I've got 'medieval' on my P6 over the last couple of years taking this more and more seriously as I think tinworm will be the death of it. The car was waxoyled for a number of years and it's still good with only a tiny weld required in my time around the rear wheel arch (a well known rust point). Last year thanks to the excellent weather, I went for a hard Dinitrol compound (479) on the underside. It comes in a can and stinks to high heaven. And it took ages to apply but then I took all the panels off, got the car on ramps and set to it with a collection of wire brushes (including a 3500s cut down special for those hard to reach places). I did the entire underside, wheel arches and as much of the base unit as I could (all four panels off). Hardest bits was the gaps between the battery box and the boot as it's about 2'' wide, I literally got my rubber gloved hands and lightly smeared it on. The interior came out, carpet up, back seats out and I painted a thin coat under the sound matting and there was no rust. Door seals can get brittle and let water in.

The other treatment I found for surface rust that is very drastic but works was a coating of Jenolite for an hour and then a Hammerite coat or two.

However, if you have a perforation due to rust, get it sorted pronto, cut and weld everytime.

In terms of sills, personally, unless they were wax injected when replaced, they are notoriously difficult to protect. I would never block breather holes and never keep a car in anything 'airtight'. Damp is a fact of life in the UK and a well vented garage I think is essential to dry a car out.

If you really want to try and protect box sills, a bone dry car and a wax injection of Dinitrol or Waxoyl is probably your best bet.
diesel/engine oil as rust prevention - Aprilia
Ankor Wax from Morris Lubricants is good stuff. The farmers use it on Combines and so on. Only £13 for 5litres from a factors.

A few years back I also used Shell 'Ensiss Oil' - that was good stuff, very thin and sticky. Comma 'Wax n Seal' also seems to do the trick.
Not a fan of Waxoyl (it doesn't penetrate, its far too think), and Dinitrol is too expensive.

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