John deere 790 problem

[sawmill1965]

two winter ago, ny son tried to start our john deere 790 and killed the battery. At the time I was gone away and someone came and boosted it. The summer I came back, I noticed that the it had became hard to start and was guttless, so I change all the fuel filter and drained the fuel. The problem persisted and I took it to a garage, they took the fuel injector pump unit and sent it somewhere else to get tested, $1000.00 later this did not fix the problem, he also changed the fuel pump (he did mention that the pump was only pushing 4PSI). Now its really hard to start and when it starts there is a think white cloud of smoke. It smells like diesel all the times, sometime worst. The frame of my loader is black by the exhaust. I tryied all kind of injector cleaners, ATF, etc... It seems that when I try to start it while pre-warming with the glow plug it starts easier. Nevertheless, the fuel seems to crawl up (climb slowly) rather than been gets up right away, its sluggish, when I attach my rototiller it wants to die. It does sound like it back fire, especially when its cold. It does better when its warm but still have slug, backfire, you know poptpopt,. Engine is a yanmar, tractor is 2004, low hours, approx 240 hrs. please help

 

[RoyJackson]

You took it to a garage...not a Deere dealer?

At this point, I'd really suggest you get the tractor to a Deere dealer and let them sort it out. If that garage mechanic wasn't a diesel guy, he may have done more damage then he fixed.


BTW, welcome to TBN!!!

 

[sawmill1965]

It was a certified farming garage.

 

[Grandad4]

+1 what Roy says. I'm not an expert on diesels, but your engine sounds like it needs some serious attention. White smoke is a classic sign of coolant getting in the combustion chamber. Your other symptoms of hard starting, lack of power, etc. could be the result of lack of compression. Just my opinion, but with symptoms like that, a good diesel technician should have ruled out possible internal engine damage before going off the deep end on fuel and injection system fixes.

Find someone else who is a trained diesel technician- a dealer shop would be a good choice - to look at it. Also, the engine should not be run any more until it's fixed as that could make the problems even worse.

 

[charleyfarmall]

I would make sure the injector is timed correctly even though it was just rebuilt. If you are not inclined to work on it yourself the best bet is to take it to Deere.