4300 engine rebuild

   / 4300 engine rebuild #1  

steviep

Silver Member
Joined
Mar 4, 2007
Messages
178
Location
Milton NH
Tractor
2001 JD 4300
So a while back I posted my jd 4300 had exhaust coming out the valve cover breathertube. Well I took it to the dealer and they tell me the cylinder walls have scoring on them. They gave me a price to fix it of 16000 , that is correct not a typo. When I get it back I will with help properly rebuild it or buy a new engine. Does anyone know who sells yanmar engines.
 
   / 4300 engine rebuild #3  
How many hours are on it?
 
   / 4300 engine rebuild #4  
$16K? WOW! I wouldn't set foot in that dealers door again. Look on tractorhouse.com you can find complete 4300 tractors with loaders on them way cheaper than that!
 
   / 4300 engine rebuild
  • Thread Starter
#5  
It has around 1050 hrs on it. I decided not to have the dealer rebuild it . A good friend of mine is going to help me rebuild it. The dealer says the cylinder has scoring on the walls.The hard part from what I can see is the tear down I believe the engine has to be removed to pull the motor.
 
   / 4300 engine rebuild #6  
Wow.

I'm guessing they just didn't want the work because a rebuild kit for that motor is only about 600 bucks on eBay.

Out of curiosity how did they come up with it being a scored cylinder wall? I would have thought smoke coming out of the valve cover breather would have been more along the valves in the head not seating causing blow-by. Smoke coming out of the oil fill cap was what I thought was the culprit for scored cylinder walls or rings.

Are you noticing a significant loss of power with the engine or is this something that you just happened to notice one day while you had the hood open on the tractor?

I would hate to see you do a complete teardown/rebuild if it isn't even necessary. Yanmar builds pretty good engines, a thousand hours shouldn't be anything for the engine.
 
   / 4300 engine rebuild #7  
The diagnoses and quote to repair is highly suspect. Good call on not going with the dealer.
 
   / 4300 engine rebuild
  • Thread Starter
#8  
The tractor blows grey exhaust out the valve cover tube and the dip stick. Once I get it home I will have better idea what's going on.
 
   / 4300 engine rebuild #9  
Before tearing it down you need to investigate the problem.
It could even be a head gasket blown into an area putting exhaust into the crankcase.
Or a cracked head doing the same thing.
 
   / 4300 engine rebuild #10  
What would cause scoring on the cylinder walls?
 
 
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