I have an AR SXMV4G40 Pump 3450rpm direct drive 4gpm 4000 psi coupled to a 13hp Honda engine. I'm using a size 4 nozzle. I cant get 3,000 psi no matter what I do, let alone 4,000. Even with a new tip. The unloader hasn't been touched, it was set at max psi since, I've been regulating the pressure with tips. I still get 4gpm flow, atleast without a tip in the gun (tested with a 5 gal bucket and a timer) and there is no excessive vibrating in the hoses or anything. It acts totally normal except for 1,000 psi or so missing. I've gotten water in the pump oil a few times but only after water has come in contact with the pump. The oil cap is vented and water can get down inside it. I have run the pump with fresh oil and the water doesn't come back unless i accidentally drive through the rain or spray water at it (not on purpose of course). So i dont think its a seal leak. Also a worn out seal I would think would cause a strong vibration in the hoses and an audible pulse in the spray. The last pump i wore out had those symptoms (i assume from two seals working fine and one not working fine).
Anyways, I have a new tip, plenty of water flow, unloader all the way open, engine RPM is fine, doesnt bog down when the trigger is pulled, etc. I'm stumped?
Also forgot to mention that the pressure on the gauge shoots up to about 4500 psi when the trigger is released which tells me the pump is capable of it, but for some reason its just not doing it.
Anyways, I have a new tip, plenty of water flow, unloader all the way open, engine RPM is fine, doesnt bog down when the trigger is pulled, etc. I'm stumped?
Also forgot to mention that the pressure on the gauge shoots up to about 4500 psi when the trigger is released which tells me the pump is capable of it, but for some reason its just not doing it.