Having trouble with New Holland DC100 engine surging from loss of fuel. I've changed fuel water separator, canister filter and inline filter. I also changed the fuel pump, which has a hand pump mounted with it. I blew the line back to the tank to make sure it was not clogged. Nothing seems to help. It will run fine for about 15 seconds and starts slowing and smoking like it's out of fuel. after about 10 seconds, it picks back up and runs fine for about 15 seconds again. Fuel is full with fresh fuel. The dozer ran out of fuel down in the pasture and I let it sit for about a year before I put fuel in it and ran it again. I added a can of sea foam yesterday but haven't ran it yet. Anyone have any suggestions.
You may be sucking air some where . Did you bleed the system before starting?
How long did you let it run like this? if it keeps up after a few minutes, then it's sucking air like Bls said. It could be plugged as well, a year with an empty tank would turn that quart of diesel to slime which could be plugging an intake screen in the tank, or some other screen. It's usually not that hard to measure the fuel pressure coming into the injection pump to see if that's the issue, or a clear section of tubing on the return to the tank to see if it's sucking air.
Check the air filter ,sitting for that long you may have some critters in there blocking air.
Start the equipment, hop off and work the hand primer when it starts acting up.. if it picks back up and stays up, it just had air in the system. If it picks up and then dies again when you stop.. its a supply problem.. either air, a clog somewhere or your supply pump isn't working. Pull the air cleaner OUT before you start, just to eliminate air supply problems. What fuel system is on it?? and pictures?
Hey guys, thanks so much for the fast input! I have to go back to Houston tomorrow for a few days and will return. I will check all your suggestions when I get back. I like the idea of the clear section of hose. A previous owner put the inline filter on the machine, I don't think it's factory. I got to thinkin today, that may be indicative of past problems with trash in the tank. Anyway thanks for the fast responses and I appreciate it a lot!
What kind of inline fitler? a small one like you see on a lawn mower? it could be rated for gas and will have too much restriction with diesel. You want a large hose to a filter base, and an oil filter (cheap and easy to replace) to catch the garbage if there's no suction screen in the tank.
As in a 3/8 in and 3/8 out like you see on an automobile. The rubber hose coming from the tank is a 3/8 and the fitting on the filter/water separator housing is 3/8. I would assume from the factory. Looks like somebody just added the inline filter.
Komatsu and Case used an inline filter like this. I have changed them on both these brands dozer.
Check the fuel tank also and make sure it is not under suction there is a vent on it which will plug up.
OK, Finally figured it out! I think! Wix has 3 different 3/8 inline filters. A clear and a metal housing (Wix 33033) that filter down to 21 microns, for gasoline. There is a 3rd called a strainer for diesel (Wix 33270). Metal housing and filters down to 140 microns. Changed the filter to a strainer and replaced fuel hose from strainer to fuel pump with clear hose. Still had air in line coming from tank. Assumed leak in hose coming from tank, so changed line to tank to clear. Still had air in line coming out of tank. Assumed hole in pickup tube, so removed sending unit/pickup from tank. No leak. What was happening is the return line tube from injector pump and pickup tube are side by side and same length, 2" apart. My guess is, the air/fuel returning from injector pump was cycling back thru the system. Ran a hose from injector pump to fuel drum and allowed air to go to drum and the air cleared up immediately. The fuel return line should be cut shorter in the tank so the air doesn't leave the tube next to the pickup. Anyway, machine runs perfect! Thanks for all you guys help!
Good find. Simple fix to a complex issue.