Went to use my old Rover with 3.5hp briggs on it today.
It doesn't get used much, the fuel in the tank was admittedly 98 ron bought in early May. I normally have no problems using 98 up to 5 months old (though I don't normally let it sit more than 3-4).
I used it a couple weeks ago and the tank was clean, then refilled with new fuel (a bit dark and didn't look at the state of the tank and ran it 5 minutes). 2 weeks later (today) I take it out and look in the tank and it looked like it was full of milk. Tipped it out and there was a white slime layer through the tank.
Fuel as shown was milky, but no water settled after sitting 20 mins (it is stored in shed that isn't damp). It started with new fuel and when mowing it ran pretty poorly. It was also idling at 2200 rpm - I had it dialed into 1750rpm last mow. Vacujet carb by the way.
I pulled the carby and the white silt in the tank had completely bypassed the pickup filter and clagged up the main jet a bit and the idle nozzle completely.
Filled the tank full of washers and nuts and shook it around - tonne of silt came out.
Now running alright but I have never had this before.
What the hell happened? Checked for ethanol and its pure petrol without alcohol.
Did an old fuel additive caltex put in the may fuel react with the new august fuel?
