Engine runs but back fires then dies when put under load

either the engine is worn and has no power or the pump is overloading the engine........

squeeze the trigger before you turn on the water.....
try no high pressure hose to make sure the water exits the pump ok

To start ensure that is not a carb problem, and that the engine is not chocking because of incorrect carburetor settings. The carb should also taken apart and cleaned.

Try also running the engine without fuel tank cap, if engine runs fine replace the tank cap.

if carburetor, fuel filter, tank and fuel lines are ok it may be a faulty fuel pump failing. To test the fuel pump, insert a pressure gauge tool like this in the lines out from fuel pump.

Regards.

you need to clean the jet and fuel tube in carburetor you have to remove the fuel bowl to do this.

Be sure you are getting good fire to the plugs and if you are take a spray bottle and spray fuel into the tbi and if it runs ok then you have a fuel problem, your pressure regulator in the tbi could be week and not putting enough fuel to the tbi. If not you need to pull the o2 sensor out ahead of the catalytic converter and see if it runs ok if it does then you either have a plugged cat or muffler. To much back pressure on the engine will not allow it to draw fuel into the cylinders and fire the fuel. Hope this helps.

does the engine die or the pressure if its the engine leave the gas cap loose and see if it stays running the vent could be plugged is it loosing spark when it dies check it for spark is it fuel does it fire back up or does it need to cool off for a while like the coil is bad

if it is an older dodge with electronic ignition the gap is closing up and the advancement plate is hitting the reluctor the star shaped reluctor on distributor shaft and that will cause it to backfire etc.
replaced distributor.

Dear Modad,
First one must see if the problem is in the Honda engine or in the pump. So you must try the Honda with no load. You can remove the gun from the pump, but leave the water supply going into the pump. In this way you still have some cooling effect from the water. Now with no load you try the Honda engine. If it is possible tune and set the Honda engine to work correctly. Now if the Honda runs smoothly,...then the problem is in the pump. Regarding the pump try the system by attaching the gun with no NOZZLE/ or LANCE. Open and close the gun to see reaction of Honda Engine. If in this case the Honda runs OK....then attach a NOZZLE so that you have pressure and load. If the Honda starts to die down, this could be that the Honda needs servicing. This like having a car and uphill it will stall and dies down. Here the engine needs servicing. One small thing to look for. I came across Honda driven pumps which have a cable coming from the Honda's carbureter to the head of the pump. When the gun is released the cable is pulled from the head of the pump by means of a piston type valve and this in turn will reduce the speed of the Honda. As you see it is difficult for me to pinpoint the real cause when I do not know the model number and type of pump you have. But if you go by these guide lines you shuld find the fault. Remember...ALWAYS try HONDA ENGINE without load first. I also wish to add that the Honda could be working OK...but then the pump has some problem that it is stopping the Honda. So the pump could also for some reason be jammed and this needs the pump to be serviced. Another hint is very simple. If the Honda is not getting to its maximum power and revs...then the pump will drop pressure.
I gave you various hints to tackle the problem by simple elimination. But you must be able to know how to service the Honda or Pump yourself. To repeat and remind you...check the honda and service the Honda with NO LOAD!! Thyen tackle the PUMP.
Regards,
Fulltech.

problem like this on garden tractor ,was weak coil ,-when engine at low manifold pressure[idle] spark could jump gap and fire cylinder ,higher pressure /under load-wouldn't fire...check color of spark -orange,yellow ,white spark=weak, blue spark is stronge,

likely you air to fuel ratio is too lean, runs mean and hot but under load dies. then floods the carb.
when it happens pull the plug ,
kill engine :
is there a lot of gas or none.
remove the filter and watch the action of the carb does it open and close easily is the filter clean.
try supplying it more gas turn the gas supply screw 1/2 CCW and see if it will stay running, if not add more.
( NOT the idle screw on the carb side w/spring )
By the way did a bit of water come out if not the clutch/pump may be binding or stuck with soap goop.back flush with hot water.