docrigo

Gents, need some help on figuring out what to do next. I am a novice when it comes to working on engines. I have a diesel Zetor 5340. Ran into a problem someone else mentioned in another thread - last year with dirt in a banjo fitting. Cleaned that up and my tractor ran fine until this fall. I found more crud in the same spot - dead lady bug shells. This happens in a fitting before the primary fuel filter / water separator bulb which on my unit which also has a screen in it. Fuel then runs to the big fuel filter and then up to the injector pump manifold. A return to the fuel tank comes off of the top of the injector pump. The system has a priming pump which pulls fuel into the primary fuel filter and then pumps it out. It should normally require 10-15 pumps to get fuel filled in the injector pump. Normally when this is working properly, you eventually hear air bubbles in the fuel tank from the excess fuel pushing air through the return line.

I eventually cleaned the lines and drained the tank and screened all the fuel as I put it back into the tank. The tractor ran fine for several hours. I was splitting wood and moving some gravel around and scraping the driveway. I parked it after this activity and now it will not continue running. It will start and run for about 15 sec but stalls and will not restart unless I prime it again. Also, the priming action is different that what was normal. I removed the fuel lines a various points to check that fuel was flowing and it was. Then I removed the line from the overflow on the injector pump and ran a clear line into a bucket. The fuel did come out but not consistently. It seemed to build up pressure a little (I could feel this in the priming pump i.e. a little back pressure) and about every 12-14 pumps a stream of fuel would come out some of it very foamy. Some fuel did come out with each primer pump but it was a small amount.

I don't think anything is broken (pump?) as it was running fine when I stopped it. I've checked again for obstructions in the lines and they seem fine. I tried tightening down some connections and hoses thinking that maybe it was drawing in air somewhere but I didn't find anything that seemed like it was the cause and it is still doing the same thing.

As a precaution to preventing more crud in my fuel, I added a fuel filter to my fuel storage tank.

Any suggestions on what to look at next would be very welcome.

Thanks very much.

BelarusBulldog

Sounds like air or dirt in your injector pump. Have you tried bleeding the injectors? Other than that, it does sound like air getting into the fuel system somewhere!

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docrigo

Thanks. I also spoke with a relative who works on tractors and got similar input so I have some work set out for me. Appreciate the information.

docrigo

I got this fixed evevtually. It was air bleeding into the fuel system I think from multiple places where I has taken parts of the fuel system apart. Nothing like a problem like this to make you learn about your tractor. I also stripped the threads in the fuel bowl assenbly necessitating buying a new one. It turns out that there is a company DSF Imports in my town (Milton, Ontario) that has or sources parts for most tractors including Zetor. I just happened across their website www.dsfimports.com while searching - it was not the site that came up from the usual searches. It anyone in Canada needs parts for older tractors they can get them and then you don't need to deal with the hassle of ordering from the US.

BelarusBulldog

Glad to hear everything work out for you. Here is another great place you may want to check out. www.canadiantractorpartsdirect.com
Talk to Sean.
1-877-319-0059

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Plowing, it's snow much fun!