John Deere 990

   / John Deere 990 #1  

lazy b farms

New member
Joined
Apr 9, 2016
Messages
16
Location
white deer texas
Tractor
6640 see
Needing some help on my 990. For some reason the crankcase is filling with Diesel. Drained nearly 2 and a half gallons out today. Where could it be coming from? Any help would be greatly appreciated.
 
   / John Deere 990 #3  
There are three possible routes for fuel to enter the lubrication system

Fuel lift pump – The diaphragm can split providing a route for diesel to enter the engine crank case.
Injector pump – Injector pump shaft seals have been known to fail.
Damaged Injectors – Leaking injector nozzles during periods of inactivity can drip their contents into the cylinder which then runs down between the piston and bore into the sump.
 
   / John Deere 990
  • Thread Starter
#5  
Finally got back on it this afternoon and removed the fuel pump and injection pump. Planning on taking them in to have checked out. I am wondering though if tractor starts and runs good could it still be an Injector? Starts right up every time and smokes very little.
 
 
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