clogged fuel lines on 4020

[owens73]

I filled a 6 gal plastic fuel tank to put diesel in for my tractor. Didn't know it at the time, but the tank had debris in it. Later, while operating the tractor, it had a sudden loss of power. I changed both fuel filters and it ran at full power for a few seconds then lost power again. I'm guessing the line has debris in it and that the clog is between the filter and the tank. How do I clean out the line? I assume I need to empty the tank and clean it out, as well? Can that only be done by taking off the tank? Thanks.

Steve

 

[Tx Jim]

Yes the fuel tank can be cleaned by removal and cleaning. Temporarily you may get by with blowing compressed air in the line from fuel filter to the tank. Have you ever drained the bottom of the tank to remove H2O? There's a drain cock on the bottom for this.

 

[owens73]

No, I haven't. I didn't know that was necessary or even an option. I've only had the tractor a couple weeks. I will do that, though. Thanks. The internet is surprisingly pretty empty with info regarding the tractor: not very many parts images, websites dedicated to explanations about repair, etc. I just downloaded an operator's manual and that has a lot of helpful info. Thanks, again.

Steve

 

[jenkinsph]

Steve,
Lots of us think the 4020 was the best tractor Deere ever made. Deere's website has all the parts and drawings you should need just sign up to the parts website free to the public and provides a wealth of information. You can also get the shop manuals on CD too. Lots of these tractors were built and are still popular today.

Here's the link, John Deere - Parts Catalog

 

[roush9799]

I'd take the line loose from the filters, and the other end from the tank and blow air back through it. Then, I'd flush the tank out well before putting the line back on. Could be by chance that you plugged the new filter(s) already if there's a lot of debris. What year is the tractor, the earlier ones had the canister filters, and the later ones had the square one. Possible that an injector got plugged, you can take them off and take them to a dealer and they will clean them and test them for you. May even be possible you have air in the system still after changing the filters.

 

[roush9799]

I thought of this too, did you shut the fuel off when you changed the filters? And remember to turn it back on? I've done that before too.

 

[owens73]

Steve, thanks for the link to the JD parts website. Very helpful. roush, its a 64 model so it has the screw-on canisters. I didn't shut off the fuel line when I changed the filters. I didn't properly bleed the lines, I don't think. After I put the new filters on, I pumped the hand primer about 50 times then cranked the tractor. That's when it ran fine for a few seconds and then lost almost all power. I shut off the tractor and pumped the primer another 50 times or so and it wouldn't crank the second time. From what I read in the operator manual, to properly bleed the line, I'd have to loosen the bleed valve. Is that right? Is that the little plastic turnscrew on the bottom of the lower fuel filter?

 

[jenkinsph]

You should have the bleeders top and bottom of the filters to get all the air out. Try that before cracking the injector lines. Tyoically you would bleed the air from the top plastic screw and water from the bottom plastic screw on double stacked filters. Some of the Deere's had the two filters side by side, primary and secondary. My 4020 had a cube shaped filter IIRC.

 

[Tx Jim]

owens73
Sounds as if air is the problem not debris. After opening top bleeder screw on filter and pumping until air-free fuel comes out then loosen supply line at inj pump and pump until air free fuel comes out,then tightened line. If engine still won't crank then inj lines at injectors will need to be loosened to let air out.

CAUTION: never put you fingers around an inj line with diesel fuel spraying out. The fuel can get injected under the skin which is very dangerous.

 

[Tx Jim]

Some of the Deere's had the two filters side by side, primary and secondary.

3020's but not 4020's had side by side fuel filters. Also 2 cyl diesels had side by side fuel filters