Muffler started popping on my GX 690 It’s the Honda muffler.
Could it need a carburetor clean out or fuel filter change? Or something else?
Anyone know what it could be?
Is it happening while running or only throttling down to shut off?
If it have an electric fuel solenoid it may not be working correctly any longer.
while running
Does it bog down when this happens? Any smoke? It could be a bad coil, or as @PPWofLexSC suggested, it might be the fuel solenoid. Before considering those possibilities, try the following steps: clean the carburetor, check and replace the fuel filter and fuel lines, inspect and replace the spark plugs, reset the carburetor jetting, and check and adjust the valve lash if necessary.
no smoke or rough idle it’s backfiring when in bypass
I’m staying with the train of thought that a cylinder isn’t firing properly, when you kick into bypass the engine load changes and causes a backfire.
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Sounds like it’s running rich or poor combustion, have you ever replaced the spark plug?
Sounds like valves need adjusted to me.
I ran the machine for 20 minutes this morning with no backfire. I wonder if it’s the gas that’s not good and when the tank got low it had contaminants in the gas.
Possible. So it stopped doing that with fresh gas?
It was the same gas I put more in the tank I ran 50’ of hose this morning only and yesterday it was a tangled up 200’ maybe the hose being tangled yesterday put back pressure on the pump
You mean the garden hose?
If you think you had bad gas, why did you put the same gas in again??
no I was talking about the pressure hose
also it was the only gas I had available so I wanted to confirm that it was backfiring
when in bypass only
Looks like the problem is back I ran some regular high octane gas in it to get through a job now I came back and it’s backfiring really loud while in bypass. In the other thread I had a problem idling up at that time I tested the solenoid, changed the plugs and filter also did some surface rust removal on the flywheel. I hope it’s just that the machine is not happy with the regular gas or that the gas in my area is really bad but the machine is backfiring really bad now it’s super annoying.
Backfire out the exhaust usually means you’re running too rich.
Are you running ethanol free?
Did you adjust the carb?
Did you check the gap in the new spark plug?
Any cracks or leaks anywhere after the carb?
I usually run ethanol free but the last time I used the machine I ran a 1/2 tank of super unleaded. Then today I drained the super unleaded and replaced with Rec 90 gas but it still did it. I did not gap the new plugs but they are the recommended plugs for the machine and I don’t know how to adjust the carb. The machine only has 360 or so hrs on it. I don’t think it was doing this before I changed the gas again. The last time I mixed rec90 with unleaded and lost power aln throttle up and started a thread about that. I should have known to use only Rec 90 gas but I was rinsing a roof and needed to finish with what was available.
This was the last time I had an issue related to fuel
Last time I swapped plugs they were over 0.040 out of the box. Had to adjust them to 0.028. Also, valve adjustment is due at 300 hours.
What kind of rpm are you seeing while bypassing? I’m wondering if it’s a governor issue.
