Cat 953Z won't start

My Cat 953 loader won't start. (ser# 20Z00654) I was pushing some brush at full throttle like you're supposed to and I stopped moving, pushed throttle to idle speed and the engine immediately started running rough with barely any power. It wouldn't throttle back up...just kind of sputtered so I limped it back to my shed and shut it off. Let it cool and tried to restart and it would only hit once or twice and sputter black smoke. Any ideas where to start my trouble shooting? I'm thinking maybe a fuel issue. I checked the bowl under the manual fuel pump, and it looked fine no debris or water.

DirtyHands said: My Cat 953 loader won't start. (ser# 20Z00654) I was pushing some brush at full throttle like you're supposed to and I stopped moving, pushed throttle to idle speed and the engine immediately started running rough with barely any power. It wouldn't throttle back up...just kind of sputtered so I limped it back to my shed and shut it off. Let it cool and tried to restart and it would only hit once or twice and sputter black smoke. Any ideas where to start my trouble shooting? I'm thinking maybe a fuel issue. I checked the bowl under the manual fuel pump, and it looked fine no debris or water. Click to expand... Don't have a schematic or fuel diagram for your unit , when were all the fuel filters changed last, does fuel free flow if line disconnected before the filter. Have you checked if fuel cap is under vacuum. How many hours on unit? Will it run or start with 1 psi of air being pushed into fuel tank opening with rag ball over opening. Have you checked battery voltage and all cables in case you do have a fuel solenoid. Maybe post some pictures of around the fuel pump and filter area. Simon C

It's is probably out of fuel or sucking air

First check your fuel level. If it is ok go to the fuel primer pump and remove the bowl. Clean the Screen and check for algea. I see you already checked the pre screen. While that was apart , you can take a airhose and nozzle and spray air back in to the fuel entry line to insure the fuel pickup is not blocked. Next step is the main filter and are you getting fuel to the pump. Use the primer pump it should pump up and become very hard to push. Replace the main fuel filter. I always fill them up with fresh diesel fuel before reinstalling. Loosen the bolt on the fuel piump and press the primer until fuel comes out on the pump. close the bolt press it some more does it get tight? If the primer pump does not work good take it off and go buy the new pump unit it is about 130.00 or so. Don't bother trying to rebuild it. This part must work right. Have someone else try to crank it as you stroke the fuel primer pump. If it fails to start you will then need to loosen the lines at the injectors and use the primer pump to get the air out. One of my 20zs rubbed a hole in the metal fuel tube and started sucking air. Had to braze the hole up. My 963 just recently had the fuel filter go bad and spilt at the top amd started leaking fuel. It did not stop running just covered the radiator and rear of the machine in diesel fuel. Luckily I always stop if I smell any fluids while working. Had an algea problem on the 63. 5 filters later and cleaning the screen 10 times and it finally cleared up. Another machine had some metal debris block the pickup. I used a wire and broke them up. Then it had a loose filter housing sucking air. Would not give full power.

Might also want to check the throttle linkage might have popped apart some where

Thanks guys, I'm going to check all these suggestions hopefully this weekend. Fuel was topped off prior to using it and I did notice a lot of rust in the fuel tank. I did already take bowl off of the primer pump and it was clean and the pump did get hard to push after a few pumps. I will try blowing back into tank. Is there a screen at the bottom of the fuel tank?

DirtyHands said: Is there a screen at the bottom of the fuel tank? Click to expand... Don't think so, but there is an elbow right at the start of the fuel delivery line underneath the tank that might be a major suspect to plug up with debris. Have you tried opening the ball valve for the water/sediment drain on the bottom of the fuel tank to see what comes out.?

Throttle linkages are all good. Opened sump drain and fuels runs clear immediately. Blew air back into tank from primer pump with no issue. The fuel filter has about 200 hours on it so I will change it next. I've got to charge batteries first. Thanks for the ideas I will keep you posted as I go.

There should be a small (3/8" or smaller) fuel line connection fitting on top of the fuel tank that has a fairly narrow internal cross-section. I had one that was clogged. I recommend checking that too.

My fuel line was clogged here.

Fuel will leak through almost anything. But with enough junk in an elbow it will shut down if under load. Simon C

I have been tied up with work and no time to work on machine. I will keep you all posted and hit you with more questions when I get back to it. BTW what is this for? I thought I had posted this earlier but apparently didn't.

Fuel pressure sensor.

Seeing as it has 2 wires connected to it rather than 3 I would say it’s a fuel pressure switch.