Oxford RT 110 Oil check

[Mark Vine]

Hi.I have an Oxford RT 110 that’s been sitting around for twenty plus years undercover and out in the open. I have tried to protect it from direct rain etc. I recently opened it to discover the internal mechanism covered in a thick oily dark brown deposit. The oil is also dark brown but at the right level to make me think the is no water in it. It also does NOT look like an oil water emulation. I have cleaned off the deposits from the coil, transformer, contacts etc(. Being careful to protect myself and dispose of the waste safely). And specifically cleaned the contacts back to bright metal. Now back together but to be certain I would like a opinion on the risks and chances of it working and if the oil is a problem when not clear. I don’t really have the money to pay the 120/40 pounds for 3.75gallons of new oil it states it needs on the cover. As Lawrence Olivier asks in Marathon Man,.......... ‘Is it safe’....... many thanks for any advice. I did not take a pic after cleaning.

 

[gaz1]

have you got anymore photos to point its loverly and clean

when first looking at that it looked like it had been sat rusting away in water

i have one but havent changed its oil as of yet but i know others on here have done so

 

[Mark Vine]

No no pics of clean state but could open it again and post clean pics. I just don’t see how there could be water in it as the fluid level would be higher. Wouldn’t it? Thanks for your response. I do see how this deposit could be the result of rusting of the top which would explain the red coloring. So is the oil saturated with metal and therefore electrically conductive???

 

[jimbo84]

Might be wrong on the member it was but I think @brightspark has put up some pictures of the inside of his when he pulled it apart. Might be able to advise.

There might be a cheaper oil that would work but not sure.

I have a 140 (I think) but never had it in bits.

 

[brightspark]

the contacts are all uninsulated and rely on the oil for cooling and the insulation. if u recon the oil is clean and goes back in the only way to tell if everything is ok is do an insulation megger test on the welder to see if there is any earth leakage if there isn't any give it a go if there is the oil will be contaminated or the windings will be down would have been better to test it out of the oil and cleaned before immersing it

 

[WorkshopChris]

Looks like rust contamination to me has obviously been damp from the green above the oil/water line.
Have you put a meter between the main earth and primary windings?
As above a high voltage insulation test would be better.

 

[Mark Vine]

Thanks everyone for all those thoughts. I will try to do those tests I can and get back to you all. Does not give me much hope of avoiding replacing the oil,particularly the comment about the green copper corrosion.

 

[brightspark]

pity u didn't know any of the guys working on the high voltage transformers they test the oil on them for carbon contamination .reason being there over 11 000 volts but still well clean for 240v operation