Hello there, I've been asked to look at a 220 Daewoo excavator that's adding over a gallon of fuel to the oil in 8 hours. Well pulled the fuel pump off and checked it and no leaks so I pulled the injection pump and no obvious leaks so I filled the fuel chamber and added a little pressure and worked the pump nothing leaking into the oil chamber. Mechanic before me told them the fuel is going around the rings well ok. It runs perfect no smoking to show over fuel or wet stacking. I'd like to get the injection pump tested but I'm in remote Alaska so that's not an option. Ya this one has me scratching my head so any ideas
U can check the inj pump for leaking fuel past the p & b’s.. Remove the side cover and drain the oil out the best u can. Lay the pump in a parts washer and fill the pump up w cleaning fluid.. Rig up an air pressure regulator and hook it to the pump inlet and block off the return.. Add 25-35psi of air in the inlet and check for bubbles at the plunger and barrels.. It works, I’ve done it a million times.. Hope u find the problem..
I'm not familiar with Daewoo's but is there could be a chance that the fuel transfer pump is the problem? They are actuated by the camshaft, I think. But I may be wrong again.
Said he did that.. But they are notorious for leaking at the seal at the rod that actuates the piston.. Plug off the outlet and put air in the inlet and spray w soapy water or dunk in a bucket..
TPG has spoken. I'd double check that transfer pump if that's what TPG says. I agree that it's not adding a gallon in 8 hours leaking by the piston rings in an otherwise good running engine. (yesterday I couldn't spell mekanic, and today I is one!)
Thanks for advice. I did some pressure testing and submerging no bubbles. I finally after putting it in the lathe and hooking up a fuel system and injectors it showed the leaks. It started leaking around the plungers and barrels after it had the added pressure from the injectors hooked up. Again thank you all for your help
Have u tried re-torquing the delivery valve holders.(top nuts) 35 ftlbs..