I have ordered this
from
Mishimoto. I am hoping it will fit in the filler hole - will test it on receipt - and will also try it in the drain hole when I do the 10k oil change. I like the idea of a larger magnet.
I'm a nervous nellie when it comes to this sort of stuff. I've already asked Votex for more info on how they secure and QA the magnet, to which they have replied:
"The adhesive used is the best on the market and is magnet specific and permanent. In testing the polymers strengthened when being exposed to oil. All of our drain plugs are QC'd before leaving our warehouse."
I bought a similar SST magnetic drain plug for a new VW Golf TDI in 2003. It was supplied with a plastic washer. By the next oil change both the plug and the magnet were loose. Of course the oil gets hot and the diesel engine vibrates.
But we have the advantage of customer reviews these days and they seem to be highly supportive of Votek's plugs.
The Mishimoto plug will fit fine but to a large extent the application details are left up to the customer. I'm not sure why Dowty washers are popular as it's not the sealing that's the primary task, it's keeping the plug secure. Dowty washers are made for high pressure hydraulic applications with steel fittings and I'm unsure if the aluminium surround will deform during the install in our lightly-torqued application. The soft washers we are using now of course deform to match the fine detail of both surfaces and as such are good at keeping the plug secure. Sealing against oil seepage is just icing on the cake.
The long magnet certainly improves the chances of catching particles. It looks like a high quality part but the first thing that I'm thinking about is what sort of material is it (cast or formed) and will it resist the continuous impinging flow of oil. Will there be flow eddies that will induce a vibration and fatigue-stress the magnet in a bending mode? The other issue is differential thermal expansion between the aluminium plug and magnet and how the glue handles that, although the Kona gearbox barely gets lukewarm. My gut says all this is
probably fine but my engineering side says don't start off being biased! My conservative take on this, since I don't have the tools to carry out a formal analysis, is that it's more risky than the Votex product and that alone would put me off.
I believe the short Votex magnet will be sufficiently effective. Particles need to be right there at the magnet to stick, they don't get pulled from far away. Every mm³ of oil containing a particle of steel will have a very high probability of momentarily being adjacent to the magnet over a long period of running time, a wild estimate might be every hour driving. That time could be reduced by increasing the magnetic area or strength but it's going to be good enough.
My Suzuki 4x4 has very weak ceramic magnets on the various gear oil drain plugs and the oil always comes out in great condition.
I would still like to see a used oil analysis on the old fluid. There are companies in North America that routinely do this - mainly for fleets, and it isn't hugely expensive.
One owner on Reddit said they'd do that but certainly in NZ there are no inexpensive consumer-oriented analysis services like there are in N. America. In any case I'm confident I know what's in it. It's not like in an engine where there are a dozen potential contaminants.
*****
I did write our NZ importer:
Hello,
I’ve owned a Kona Electric since Oct 2018 and am a degreed mechanical engineer with a fair amount of industrial power transmission experience.
Here’s the issue I’ve uncovered and would like to make you aware of:
The reduction gearbox in the Kona, a simple splash-lubricated design, is notable in that it appears to be missing a magnet on the inside surface normally installed to sequester ferrous wear particles.
All gearboxes with steel gears that do not have pumped fine particle filtration normally have this feature, in both automotive and industrial applications.
Without the benefit of a magnet, all particles resulting from normal gear wear (especially during the first 1,000 km) remain circulating in the oil.
These hard steel particles become crushed down to a fine dust when running through rolling-element bearings and gears, eventually making the oil look black in colour.
The end result is that ball and roller bearings suffer from this moderate abuse and will become noisy. That does not necessarily guarantee a complete gearbox failure during the vehicle’s service lifetime but the gearbox will be operating in an unnecessarily deteriorated state for only saving the cost of a small magnet.
Often a magnet is placed on the end of the drain plug for ease of cleaning, sometimes a second on the filler plug. The Nissan Leaf for example, having a very similar gearbox, is designed with both.
The (original) Ioniq and Kia Niro appear to have an identical gearbox design to the Kona.
My recommendations:
At minimum I would suggest that all these models have a one-time gear reducer oil change between 1,000 to 5,000 km, or at their next service before the oil change currently called for at 120,000 km.
That alone will greatly improve the chances of an adequate service life.
Even better, Hyundai could review the deficiency and provide a replacement magnetic drain plug and oil change as a TSB.
Please ask if you have any questions.
Thanks for reading and best regards.