I recently purchased a Case 1150E military dozer. When I first ran it I noticed it was low on power. So I thought I would replace both fuel filters and drain the tank since it came from a military base where it has been sitting with JP fuel in it. I replaced it with diesel and after finally getting it started it sounded great. Well after a few minutes of letting it warm up it went back to low power. The RPMs would barely go above idle with the pedal to the floor. In low gear it could barely make it up a slight grade. I shut it off and let it sit for about 20-30 minutes and when it cranked up it sounded great full RPMs and turbo spooling up. Then after a couple minutes it would be back to low RPMs and no power. Oil pressure is great when I first start and get the RPMs up. I cracked each injector and I could hear a change in performance for all six. It seems like I am getting plenty of fuel but I don't know. Any help would be appreciated.
Sounds like the fuel supply line from the tank or the tank shut off valve has a partial clog. Take the line off at the lift pump to check the free flow.
Try rigging up a makeshift fuel tank ie a 25 litre drum and put the fuel line in that if it works ok then its a blockage in the fuel line from tank.
Well your running the 6T-590 engine in that machine. I would park it with the fuel tank drain low on a slope. drain the fuel again and remove the plug and flush. Remove the two shut off valves and fittings, blow out good, do the same to the lines going to the lift pump and return fuel. There is no telling what may be floating in that fuel tank, or lines up to the fuel filter base. Your filter base has a fitting that screws into you filter while also secures the base plate, to the head, this will sometimes loosen when changing the filter and cause a air leak. The shut off valve at the injection pump should have 24 Volts on it with the switch on, you may want to screw it out and remove the spring and plunger, reinstall the valve and try it. You should have a lever on the pump to shut it off by hand. Does your machine still have the compressor and engine fan cutout hooked up.
I will try flushing tank and lines tomorrow. Are you talking about an A/C compressor? I am not sure what other compressor would be on it or where it is? The fan has a cutoff switch but I am not sure if it is hooked up. I have to drive three hours to the dozer so hopefully I can get some good results. Thanks for the help.
The machine has a small air compressor, 24 volt that works with the engine fan pulley, mounted up in the dash area on the engine side, when you throw the dash switch the fan will stop turning allowing a water crossing without doing damage to the rad core. Getting back to the running issue, rags, grade stakes, rust chips, wood chips, little silver seals from additive containers, leaves, can be found in fuel tanks just floating around waiting to closeup the main fuel line. May also check the tank vent. You may get lucky and see something stuck in the inlet pipe from the tank with the fuel drained out.
Well I drained the tank and a bunch of rust came out. So I removed the fuel gauge float to get a better look and it has all kinds of rust on the bottom. I was not able to get the large drain off because I am assuming it is rusted on and I didn't have the right tools to try. I plan to remove the tank and give it a good flushing. It has a steel line inside that goes from the outlet of the tank to the center for the pickup. I guess all I can do is blow compressed air through it. Hopefully I can get back at it by the end of the week.
Along with the filters , I think there is a small screen where the fuel supply enters the pump. These are bad about clogging up as well.