650 smokes

Oldtink · Dec 7, 2011

My old 650 JD has been putting out some blue smoke until it warms up lately but it doesn't do it at every cold start.
It has 2600 hrs on it and otherwise runs fine and been a great little tractor for me.
Any ideas?

beenthere · Dec 7, 2011

What are the pre-heaters (or glow plugs) like? Working still?
That is pretty classic for no pre-heat to aid in starting.

No harm no foul - as long as it starts and runs.

kuboman · Dec 7, 2011

You may have weak glow plugs or even one not working. Also a real good injector cleaner/conditioner mixed with the diesel might help.

Oldtink · Dec 8, 2011

I did just start using Amsoil's Diesel Concentrate Performance Fuel Additive (ADF) this past summer after switching to ULSD fuel. Maybe it loosening some crud in the fuel system. I guess I'd have to remember there is 24 years of fuel residue in there.
I hope that's all it is.

kuboman · Dec 8, 2011

Unless it is starting poorer than it did I would not worry too much about it. 2600hrs is not new anymore. Blue smoke when cold is a sign of incomplete combustion which can be caused by just general wear on everything or the injectors spray pattern may have degraded some. Run conditioner in it for quite some time and if it is no better or worse don't worry. When you get blue smoke after it is warm may be the time to have the injectors serviced.