Hi KB,

If your fuel contains any appreciable amount of ethanol (most do, these days), that is likely your problem. There are fuels without ethanol for small engines or stabilising additives. Some additives work and some are likely snake oil.

Better to avoid the problem than forever cleaning jets. Donnyboy73, on youtube, likely gives some reasonable advice.

Hi KB

I used to run until recently a couple of classic bikes and was plagued with fuel problems caused by the ethanol in petrol attracting moisture. A friend recommended Sta-Bil fuel stabiliser and it does work really well I could leave a bike over the winter and it would start no problem. I did used to run the float chambers empty before putting them away, but still found green corrosion and white deposits in the carbs, the Sta-Bil stopped all that. I got mine via ebay, but i think it's readily available.

Dave

Just a thought, but is the petrol old, perhaps kept in a can next to the generator? Ethanol won't damage brass, but Ethanol absorbs water which does. If it's an older engine, also possible the ethanol is attacking a plastic, and the product of that is corrosive.

Petrol might be watery out of the pump if the supply chain is wonky. Most likely suspect is an elderly roadside tank – they collect muck have to be changed periodically. Petrol taken from the bottom of an nearly empty tank can be filthy. Is there an oil refinery in New Zealand? In my part of the UK petrol has few opportunities for being mucked up because it comes from a local refinery. If New Zealand petrol is imported, the chance of contamination en-route across the Pacific to Kiwi's generator is much higher.

The ethanol in clean petrol gradually absorbs moisture from the air even if the can is closed because water molecules are smaller than petrol molecules and diffuse through the seal.

At first water absorbed by ethanol in petrol goes harmlessly into solution. But as more is absorbed, water drops out of solution and sinks to the bottom of the tank. There's a distinct risk that the end of a fuel can left standing will almost pure water, definitely bad for engines!. Also that simply draining the engine will leave a lot of water behind. I suggest:

• Use new petrol, and minimise storage time. (Perhaps monthly burn aging generator petrol in your car and refill the generator. )
• Before pouring the end of a can into the engine make sure it's not watery.
• Don't drain the carb, instead run the engine once every few weeks to warm it through and stop wet fuel settling.
• If draining for long-term storage, rinse the engine thoroughly and try hard to exclude water by wrapping etc,

Dave

I stand corrected

The green corrosion product on greased microscope slide-ways is more likely this: **LINK**

https://en.wikipedia.org/wiki/Basic_copper_carbonate

MichaelG.

.

But you might understand my confusion :

https://digitalfire.com/oxide/cuo

https://www.usgs.gov/media/images/copper-oxide-helen-folger

Edited By Michael Gilligan on 21/01/2021 08:59:50

Nearly all copper and zinc corrosion product will be soluble in household amminia solution. This will rapidly dissolve the corrosion products. Unfortunately household ammonia solution, which used to be a common cleaning agent during most of the 20 th century, is now quite difficult to find although it is readily available via ebay. If you use this wash with water afterwards and then rinse with alcohol (methalated spirit, denatured alcohol) and leave to dry.