My newly rebuilt 188 runs really strong for 20 to 30 minutes starts loping and dies. Will not restart. When I take the bleed screw out of the secondary fuel filter it looks dry, so i fill it up. When I do this it restarts and runs another 20 minutes. Tank is full to the top. I thought fuel was suppose to run out the top of the fuel filter when the bleed screw is removed. Should I look at replacing the primary fuel line? could the return line be clogged? Injection pump was just rebuilt. Thanks
I know nothing of the model in question.....so take this for what it's worth. This could be a fuel venting issue. have you checked the caps for proper venting??
Fuel issue I would drain some fuel out of the drain valve on the rear right hand drain and take a look at it. Your machine is a gravity system, with the bleeder screw out of the top filter it should run out freely with the tank full. When the machine cuts off, open the bleeder and let it set for a few min. If the flow does not start loosen or remove the fuel cap, if flow starts back replace the fuel cap. If no flow after removing the cap, use some air pressure and blow back threw the fuel line, if flow starts back, prime your system and start. A lower filter can be full of water/trash and not let the fuel threw also. The fuel shutoff in the tank has a raised inlet pipe also, trash floating in the tank could be sucked over it and starve the system until the suction is released and floats away until the next time. So spin the lower filter off and dump it in a clean bucket see how much water and trash is in it, if you don't have a new one, make sure the gasket is in place and screw the old one back on, open the fuel shut off, and the top bleeder screw and see if your flow has picked up. Like sstocker31 said could be just a vent issue.
I forgot to add that when I took out the bleed screw for the secondary it made a pssssh. So it had built either a vacuum or pressure. its a 188 diesel too.