Chassis Cleaning

[Murphyv310]

Hi.
No doubt many of us have bought or given a Radio, TV or other vintage items. If you are fortunate it may only have a "Light layer of dust" as one collector says on another forum. Knowing me and others including our friend Geordie McBoyne get items at the opposite end of the spectrum.
The Recent acquisition of the Soviet Record TV made me do some more cleaning. I've a couple of scrap Murphy V310's ( Sorry no scrap Trevor's) and one that had been cannibalised I decided to give it a wash to show the results I get.

In a way it was a bit of a disaster as 30 odd seconds into shooting my first video there was a parcel delivery which took three or four minutes, then another interruption that wasted another couple of minutes. I had already sprayed Traffic Film Remover (TFR) onto the chassis using a 50% diluted mix which is stronger than I usually use. Leaving it on too long causes it to eat into alloy. In fact Bicarbonate of soda does the same on aluminium.

The difference after cleaning and rinsing using a pressure washer is spectacular and so long as you don't leave the TFR on for longer than 2 minutes all is well. If you have a hot water pressure washer then the result is even better, mine is cold and 110 bar running pressure (an industrial type). it's important to start the drying process immediately you have finished, an air line is useful to blow out the excess water, a steady stream of warm air then can be used from a hairdryer or 1Kw fan heater, there is no need to get the chassis and components burning hot, 40 to 50c is fine so long as the airflow is good. There is also no need to rinse with deionised water, (certainly in this area)

Some won't attempt this, that's of course you decision but I have done this for many years and with PCB sets too with no issues, just make sure you dry it off as soon as the rinsing is complete.

I'd also like to see how other clean up their projects.

https://youtu.be/q1rah536sAQ

[ppppenguin]

Recently Paul Marshall, chairman of the BECG, restored a Marconi HT power supply. 250V at 1.25A stabilised. He had two units, which had more or less been saved from a swamp. One of the first steps was to remove the remains of a rat. I don't think he pressure washed the units. Trevor, I think your methods might have been useful.

The photo is after basic hygiene had been done.

If you're a friend of the BECG (no obligations, apart from consenting to be on our mailing list) the story of this PSU is in our latest newsletter which is emailed to friends. Older newsletters are on our website: https://becg.org.uk/newsletters/

[Murphyv310]

Hi Jeffery.
Many thanks for the link.
I've requested to join the Private FB Group.

[Cleggy]

The difference after cleaning and rinsing using a pressure washer is spectacular and so long as you don't leave the TFR on for longer than 2 minutes all is well. If you have a hot water pressure washer then the result is even better, mine is cold and 110 bar running pressure (an industrial type). 

After using the TFR, I wonder if so much pressure is needed, or advisable?  What about putting some hot water and appropriate detergent in a garden sprayer (the ones with a hefty hand pump) and seeing how that does?  I've never used a pressure washer under the bonnet of my cars, nor on the body of my cars, only the garden sprayer. The PW is restricted to the patio!

C

[Murphyv310]

Hi.
Well I worked for a company that repairs industrial cleaning equipment for nearly 8 years after I closed my Radio & TV repair business in 2006. I was already competent in vehicle repairs as I used to work weekends in a garage in my early days as a Radio and TV engineer, it did me in good stread for mechanical jobs on cars and I was able to get the hang of floor scrubbers and industrial pressure washers very quickly. I also went on courses with Karcher and Nilfisk Alto amongst others.
Some people seem to be terrified of a pressure washer on a car. In fact a sponge is far more likely to damage car paintwork than a pressure washer! There is a proviso though, you must use a fan spray, no turbo nozzles or single streams as this will lift paintwork. I wash under my bonnet twice a year and regularly do underneath with my machine, the MOT tester always says your cars are really clean and show no signs of corrosion.

Re washing the chassis, even using the pressure washer for rinsing you need to use common sense. Don't deliberately spray on line output transformers or components that can be damaged.
This year two sets were so grotty I used the method shown in the video. A Bush TV24C I got for £15 looked like a pile of scrap, it was washed as per today and now works beautifully, see it on my YouTube channel, also the Soviet Rekord was done the same way.
You could of course use TFR and then rinse with a hose on hot water, it should work fine. A toothbrush would help in corners. Remember though on alloy don't leave the TFR mix on for longer than about 2 minutes.

[AdrianPH]

Thanks for the information I have yet to have a go at the V280 I have this may give me a bit more confidence to start a clean up, would you suggest removing the oil filled EHT transformer first?

Adrian

[Murphyv310]

Hi.
I've never removed the oil filled LOPTs especially if not leaking. If they leak it has to come out as they absorb moisture, they need to be drained and dried out anyway. A dry Murphy oil filled LOPT is usually good with the execption that the U25/26 heater may not work as some have an internal resistor in series with them. A selenium or silicon EHT rectifier will of course work.

[Cleggy]

I wash under my bonnet twice a year and regularly do underneath with my machine, the MOT tester always says your cars are really clean and show no signs of corrosion.

Metal does not have to be dirty to corrode. My impression is that cars in Scotland corrode a lot because the winters are more severe than further south and more salt is used. Cars resident in coastal areas are also prone to more corrosion. The chloride ion has a fantastic ability to adhere to metal surfaces and initiate corrosion. Once on, it is very difficult to remove chloride using water alone; the Canadian Government has spent a lot of money researching this topic (their public service vehicles rot rather quickly) and the results can be found in the technical literature and are not merely "anecdotal". Cars more than ~5 years old and made of steel being corrosion-free is quite unusual.

Of course, MoT tests start at three years old and at that age they may well be corrosion-free, but it does start eventually and no amount of washing (alone) will stop that. My own two cars (average age 21 years) both have some corrosion on them, though not enough to ever get mentioned in MoT's. I attribute their good condition to the application of modern, corrosion-resistant paints and the rarity of salt on southern roads.

[Murphyv310]

Salt is certainly a killer and yes indeed Scotland's councils love the stuff even in a relatively mild winter.
I'm fussy with my cars and after a journey on salt laden roads will pressure wash underneath, I know they all have arch liners and are mildly galvanised but I still wash off the salt often daily. Up to the Pandas I ran older vehicles since around my mid 40s and never had corrosion issues. I regularly waxoyled my cars and on this Panda use a lanolin based wax treatment. That being said Fiat are extremely rust free these days. They learned the hard way, I see though some marques falling back again with some severe issues on suspension and subframes down to very poor quality powder coating.