epic 790 hydraulic pump fail, oil flowing from dip stic, bent connecting rod....and

jd110 · Feb 1, 2020

I also find it curious that the misfire smooths out when injector line was loosened. Usually loosening the line on a misfiring cylinder won't have any effect on hoh it sounds or runs. Injector may be dumping fuel without atomizing it. Dealer may be willing to put it on their pop tester since you bought it from them. I might suggest that you pull them all out and test them and also test all cylinders for compression also while injectors are out.

spruce Deere · Feb 1, 2020

That's one thing with the injector line cracking and smoothing out the engine makes me almost think the new injector is bad. On the plus side, being the 790 is a yanmar tractor in deere stickers and paint, I have found that looking at yanmar vs. deere in engine parts are a little cheaper, and still 'genuine' parts. I paid 116 bucks and some chump change for just the head gasket threw deere... And this model of yanmar engine was and is used in a wide variety of equipment.

spruce Deere · Feb 6, 2020

Alrighty, got some good news. Yarded the injectors out to take'em to my diesel dude and possibly barrow his compression tester. Oh, and the new injector that I had bought was not from deere but from another 'supplier', keep that in mind here...
I had brought the old original injector with the rest of the injectors. He wanted to pop test All the injectors wich I found a little curious, but he is the guru of all things diesel not me. Turns out the brand new injector would max out the test guage and not a single hint of atomized diesel would emit from the thing... something he has seen before smiling as he is telling me that....PM me if you want to know where not to buy aftermarket injectors.
The old original injector even with slightly buggered threads from me not having the puller adapter tight worked flawless.
So, I got most of the engine back together tonight and should see if it runs the way it should tomorrow evening

beenthere · Feb 7, 2020

Wish you well, and sure hope you get up and running again soon.

dodge man · Feb 8, 2020

I know a lot of injectors are rebuilt and not always done correctly.

spruce Deere · Feb 9, 2020

Ya, person wonders how in the 'fill in with word of choice' when the price of o.e.m parts is dropped on there lap. There is good aftermarket suppliers, stay with the ones that specialize in certain parts not the ones who seem like a universal tractor supermarket super store. Person is tempted to try some other place that seemingly require a mortgage to rebuild or repair