Hello all, I am a homeowner, but this seems to be the most active forum I could find in regards to pressure washers. I have been searching the internet for a couple weeks trying to find out what might be wrong with mine.
It is a Generac 6024, 3100psi, 2.7GPM, I have had it for ~6.5 years with no major issues, only had to replace the recoil/starter. Other than that, just routine maintenance of air filter, spark plug, and oil changes. In the past month, it has started giving me issues. It starts typically first pull every time. The problem lately is that after running for ~5 minutes, the engine bogs down and starts dropping RPM (and pressure), then jumps up and does this repeatedly until it dies, assuming I am still holding the trigger. If I let off the trigger, it goes back to running normally, but as soon as I press the trigger again, it starts that same cycle of going up and down before dying. It will allow me to restart it right away most times, but once this has happened, I might get 1-2 minutes of use before the same thing happens and sometimes it is right away. The same issue persists no matter which tip I use (0*, 15*, 25*, or 40*).
In my reading, one of the main culprits pointed to was the unloader valve. I bought a replacement as well as a pressure gauge so I could see what it was doing. With the new unloader valve, the same issue persists. I see that PSI drops from normal around 2600-2700 down to 1000-1500 when it starts the cycle of bogging. The only way I have been able to keep it going is either letting off the trigger or by taking the tip off and keeping the trigger on. When I release the trigger, it does jump back up to about 3000 rpm.
At this point, I am at a loss. I feel like it has to be an issue on the wet end, but I am not sure it makes sense to put too much more money into it, especially if it is a bad pump or something like that. Can anyone think of anything I am overlooking?