2008 John Deere 5101e Cab 4wd loader tractor

Description

2008 John Deere 5101e
Pre-emissions
Disregard the small tank on the tool box.
I am installing a new fuel pump 6/26.
I robbed the fuel pump to use on another tractor.
Cannot confirm hours
We estimate 2500
Starts runs and operates good.
Used 10 hours in hay and used no oil
It smokes when the throttle is released.
Hold at mid throttle no smoke. Release the
throttle back to idle and it will puff smoke. I
I switched the turbos to see if the problem followed the turbo
and it did not.
Dyno tested 90 hp
No blow by.
Not sure about the smoke.
Suggestions anyone about this problem?
101 hp
4 cyl diesel
Power reverser tranny with 12 forward 12 reverse
30 inch rear tires
John Deere loader
Comes with 6 ft bucket
Cab ac and heat
2 sets of rear outlets
Clean straight tractor
Ready to go
Delivery available
Sales tax applies according to state law
Ship out of state no tax
Can assist with shipping  estimate .5 per loaded mile
Allow a few days to find a hauler
Please make reasonable offers.
Low ball offers auto declined.