'Keepers' - preservation of brake pipes, etc.

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Sun 12 Mar 2023 09:15
'Keepers' - preservation of brake pipes, etc. - John F

Not much on here these days, so having read about sunflower oil in a thread here I thought I'd start a new topic. For those of use who keep their cars till they die, painting stuff onto the exposed bits underneath is advisable to avoid things like corroded brake pipes, cracked springs, rusty subframes etc. What, if anything, do you do? I had never thought of using sunflower oil.

I still have an old jar of lanolin grease I inherited thirty years ago which when heated becomes liquid enough to paint onto things but almost solidifies at room temperature. Excellent for brake pipes. I've always just painted old engine oil on springs and subframes every three years or so. The only mechanical immobilisation I had on my first Audi (100 2.0E) was when the front anti-roll bar broke. On inspection the fracture site had developed from a corroding micro crack. I had a spring break once; likewise it had been weakened by a longstanding crack - corrosion was visible half way across its diameter, the other half was a clean shiny fracture. So, rightly or wrongly, I've thought it sensible to occasionally apply something oily or painty to such items. Perhaps biennial sunflower oil in a power sprayer might be the way to go?

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Sun 12 Mar 2023 09:47
'Keepers' - preservation of brake pipes, etc. - Andrew-T

John, I suspect that the main benefit of your efforts at protection might be peace of mind, because the flaws which led to your spring fractures were quite likely present from new and would not have been prevented (but possibly delayed) by your applications of sticky stuff.

In early railway days, some serious train crashes were caused by a crankshaft fracturing at speed. Engineers and drivers knew all about the need for lubrication, so there would have been plenty of oil around, and probably most parts would have been painted. The usual reason was an undetected flaw in the casting. Clearly methods have advanced a long way since then, but I doubt that such flaws have been totally eliminated.

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Sun 12 Mar 2023 13:51
'Keepers' - preservation of brake pipes, etc. - Adampr

I used to have a Mitsubishi Delica. As a Japanese import, it had no underseal. I got it undersealed by a very odd man in Sussex who pressure washed, steamed and scrubbed it, then injected some kind of great into the sills and sprayed the entire underside (not the exhaust.....) with dinitrol bitumen. I never had any problems with rust and only got rid of it at 26 years old because the electrics were shot.

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Sun 12 Mar 2023 14:20
'Keepers' - preservation of brake pipes, etc. - Chris M

I'm with Andrew T on the springs point. Had cars with rusty springs (current 12 year old Panda has had them at the rear for at least the 6 years we've had it) and they ain't broke. But I have replaced broken springs which, with a quick wipe over with a damp cloth, look like new (apart from missing a few inches at one end).

Edited by Chris M on 12/03/2023 at 14:22

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Sun 12 Mar 2023 15:54
'Keepers' - preservation of brake pipes, etc. - edlithgow

I only started using sunflower oil on my current car, in Taiwan.

In the UK I sprayed motor oil, thinned with diesel fuel or kerosene enough to be sprayable with a cheapo plant sprayer, because thats what I had.

I wouldn't use "old oil" (which I take to mean waste used motor oil) because its toxic and unpleasant. A little unused motor oil goes a long way, especially thinned. One can scavenge it by rinsing out nominally empty oil bottles, and here in Taiwan I have a lot of hydraulic oil I dont have much other use for.

I don't know the relative effectiveness of motor oil, sunflower oil, Waxoyl, etc, and I'm not sure anyone does.

Sunflower oil eventually sets, (so will resist wash off) but takes quite a long time to do it (so will get a chance to penetrate rust. seams etc, if it doesn't get washed off first).

Once it has fully set, though, it seems possible that it might have the same problem as paints and underseals, that of trapping moisture next to the metal and actually promoting corrosion. It can also grow mould in enclosed spaces.

Latterly I spray a mixture of diesel, motor/hydraulic oil, and sunflower oil.

ITHINK the other components will probably retard the setting of the sunhflower oil and MIGHT inhibit mould. Slower setting could also be achieved by using more stable vegetable oils like Cannola, Rapeseed or Castor (though Castor is probably too expensive), faster setting by using a less stable oil like Linseed. You can also modify the oils behaviour by pre-oxidation (look up "blown oil")

Your lanolin grease is likely very effective in protecting your brake pipes, BUT

(a) It likely isn't sprayable (though I have a clever trick in mind for that)

(b) Its probably cosmetically inferior to SFO with aluminium, and cosmetics can be important for the UK MOT.

Pipes so treated look galvanised, and pits are filled in (requires some judgement as to how far it is safe to push this).

I have heard of greased/oiled brake pipes being failed by inspectors because it could hide (or mimic) leaks, which I think is less likely with the aluminised veg oil, though I havn't tried it.

Re suspension protection, I'd agree that the failures you experienced likely wouldn't have been prevented by corrosion protection. I've seen leaf spring stacks with grease nipples, and a leather sheath around the stack to retain the grease, but this might have been mostly for smoother/quieter suspension operation rather than protection.

tw.forumosa.com/t/classic-car-clubs/76122/76

Edited by edlithgow on 12/03/2023 at 16:57

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Sun 12 Mar 2023 18:24
'Keepers' - preservation of brake pipes, etc. - madf

Our 20 year old Yaris is TOTALLY rust free.

Dinitrol.

Waxoyl washes off.

I do NOT like to repeat work.

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Mon 13 Mar 2023 10:48
'Keepers' - preservation of brake pipes, etc. - Xileno

Maybe I've been lucky but I've never had a car with rusty brake pipes and I can't think of any family member who has either. No harm is wiping something on of course, maybe just some engine oil but I would use a cheap new one rather than old.

I have two tins of Waxoyl in the garage, the clear and black one. I tend to mix a little new engine oil to make it creep better and it seems to reduce washing off. I've heard Owatrol mentioned a few times on the forum with good reviews so I might use that next.

The Dinitrol v Waxoyl debate would lead to heated exchanges on the Landrover forums!

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Mon 13 Mar 2023 11:37
'Keepers' - preservation of brake pipes, etc. - galileo

Back in the days when my cars were very second hand I bought a flaring kit, a coil of "Cunifer" brake pipe and end fittings and replaced the seriously rusty ones myself, once done, no corrosion problems.

No doubt steel is cheaper which is why O/E pipes are made of that.

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Mon 13 Mar 2023 12:34
'Keepers' - preservation of brake pipes, etc. - gordonbennet

Back in the days when my cars were very second hand I bought a flaring kit, a coil of "Cunifer" brake pipe and end fittings and replaced the seriously rusty ones myself, once done, no corrosion problems.

No doubt steel is cheaper which is why O/E pipes are made of that.

Another Kunifer DIYer here back in the day, lovely material to work with.

For underbody, i spray the whole undersides with ACF50 twice a year, have painted the Landcruiser chassis in marine grease which is what i use on brake and other pipes.

This is the usual treatment method for me now, but after derusting treating and painting over as necessary.

Keeping the tin worm at bay is an involved and constant process, there is no do it once and forget method, least not where the country has a fetish for road salting...

Saturday afternoon a prime example, M6 betwen B'ham and Catthorpe, several gritters spreading tons of it, never dropped below 8'c and hovered around 12/14'c Sunday, since when its rained...you'll need to do some rust prevention to counter the futility and pointlessness of that section alone and its going on over whole swathes of the country, presumably salt now needs to be thorn down to keep the budgets valid as April approaches, batty britain.

Edit, get busy on brake maintenance soon as the salt's gone folks.

Edited by gordonbennet on 13/03/2023 at 12:37

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Tue 14 Mar 2023 01:35
'Keepers' - preservation of brake pipes, etc. - edlithgow

I actually brought a roll of kunifer brake pipe back from the UK, and a flaring kit in Japan, but the SFO/aluminium treatment has held up, so I wasted my time and money.

Of course no non-marine salting here in Taiwan, and I havnt tested it in salty Scotland, but I would expect it to be fairly effective, as long as it had a chance to set (so perhaps apply in spring or summer, ideally not driving in rain for a while)

In the UK I might use boiled linseed oil for its fast setting time.

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Tue 14 Mar 2023 08:45
'Keepers' - preservation of brake pipes, etc. - John F

It would be interesting to know if cheaper cars still use cheap steel brake pipes rather than the more modern copper nickel alloy which would be less likely to suffer significant corrosion.

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Wed 15 Mar 2023 01:15
'Keepers' - preservation of brake pipes, etc. - edlithgow

It would be interesting to know if cheaper cars still use cheap steel brake pipes rather than the more modern copper nickel alloy which would be less likely to suffer significant corrosion.

I'd bet (and assumed) that more expensive cars still used cheap steel brake pipes too.

Is this not the case?

I hadn't really thought of copper pipes as being "more modern",(I suppose they may be, but they've been around for a long while) just more expensive.

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Tue 14 Mar 2023 08:41
'Keepers' - preservation of brake pipes, etc. - Big John

Our 20 year old Yaris is TOTALLY rust free.

Dinitrol.

Waxoyl washes off.

I do NOT like to repeat work.

Agreed re Waxoyl washing off where exposed, also if injected into chassis sections the waxoyl didn't soak in well (I know after cutting out rusty metal with blobs of Waxoyl sat on top of thick rust) - was much more effective internally when mixed with clean engine oil. Didn't have to bother with that once I found Dinitrol - great stuff.

For Exposed surfaces I've been a real fan of Owatrol oil which sets to a resin type finish and doesn't wash off with rain etc.

For the exposed parts of my brake pipes I periodically protect with general purpose grease,

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Wed 15 Mar 2023 01:10
'Keepers' - preservation of brake pipes, etc. - edlithgow

When I had a dodgy manifold-downpipe joint which required periodic bodging I put bits of beercan in the downpipe with a teaspoon of portland cement, for internal corrosion resistance

(I seem to have managed a longer term bodge now, so its not getting dosed any more. There is a picture in the linked post of an exhaust pipe section just after external treatment with sunflower oil and aluminium. Its effective generally, for example on brake drums, but probably burns off exhaust pipes quite quickly)

tw.forumosa.com/t/exhausting-all-options/193821)

No objective evidence that the internal treatment works, but the theory seems sound. This is a non-cat exhaust, of course.

Outside of the pipe to the first box is wrapped in aluminium pipe sheathing (from aircon piping), with an outer layer of beercans wired over it on the straight section. An oil leak perhaps also helps to suppress surface rust.

Edited by edlithgow on 15/03/2023 at 01:37

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