Hey everyone,
I have a John Deere z525 it has the 22hp engine. I have around 65 hours on the mower. Full throttle with the deck engaged it runs great. Shut the deck off and it sputters and backfires. Issue will be present anytime engine is running above idle. Engage deck backfire goes away. I was running non ethanol gas and didn't have this issue. Recently moved and only regular pump gas is available with 10-15% ethanol. I changed spark plugs and fuel filters, issue still present. Is there a way to adjust carb to fix my issue? Or should I run higher octane? I live in Michigan I think our altitude is around 500 feet. And regular pump gas is 87 octane around here.
The idle circuit on you carburettor is clogged .
With the blades running you are running on 10% idle + 90% main jet
without blades you are running 90% idle & 10% main jet.
