For some reason that didn't happen before. When I set valve to higher flow. Instead of consistent bubbles, I get a hesitation and then a big glug, and this repeats
there are two possible problem:
1. there is a leak between the check valve and the bubble counter.
2. the hydraulic oil inside the check valve gets sticky because of the temperature.
solution, disconnect the bubble counter, blow the check valve with fast flowing co2 , then clean the hydraulic oil that comes out of the check valve as much as possible. reconnect the bubble counter, make sure there is no leak.
it seems oil travels up into air line and accumulates in the sway which acts like a drip loop
check air hose connection, make sure there is no leak, because if there is any leak the pressure in the air hose drops too low overnight, and in the morning when the solenoid turns on, there is rush of co2 from the system to the air hose, and push the mineral oil out of the bubble counter.