JD 755 losing power under load/ HELP

[Derwin]

I have a JD 755 hydro. It is losing most of it's power, almost to a stop, when going up slight inclines or if I press the forward pedal to quickly. Under this circimstance, it also produces a lot of black smoke. It seems to worsten if I am turning the power steering (using hyrdaulics) during the climb. Under load, it seems to lose significant power when using a mower. Without moving, hydraulics work fast and fine, no smoke, etc. Moving on flats it mostly ok unless I try to go to fast, then it loses.
This does not burn any oil so I'm hoping compression is ok.

Can anybody help with what the problem may be? Thanks much. /forums/images/graemlins/confused.gif

Also, can anyone tell me what the differences are between the 755 and 855 engines.

 

[Dutch445]

Derwin,
A little more info would be helpful,,
how old is the tractor? how many hours,,,
how long has it been doing this?
when is the last time you had the injection system serviced?
filters changed?
where are you located? is it extremely cold out?
is the hydraulic system ok? fluids,, pressures ,, filters changed regularly?
Help us help you with a little more info and we can see what
suggestions come up.

As far as the difference in the 755-855 motors,, I think there is a displacement difference, but that's all I know without doing some digging.


/forums/images/graemlins/cool.gif

 

[KennedyDiesel]

I would start with the simple stuff like fuel and air filters.

If the hydro oil and filter hasn't been done recently, that's also a good idea.

 

[ChadS]

Derwin,

I have an 855 and in addition to the displacement difference that another poster mentioned, the 855 has a direct injected engine and the 655/755's are indirect injected.

In regards to your tractor, clean air and clean fuel are the two most important things to start with. How does it do at higher engine speeds - say maybe 2000rpm? These are small diesels so in my experience they don't lug quite as good as larger tractors. Mine seems to be happiest at around 2000 rpm for general work that doesn't need pto speed.

Regards,
Chad