Bobcat CT 235 Not Starting

   / Bobcat CT 235 Not Starting
  • Thread Starter
#11  
Dean, If the engine cranks at a good rate, check the glow plugs are getting power at the bus bar while cranking and ensure the stop solenoid is truly retracting (and staying retracted) when the key is on. If that all checks out, then check that the injection pump rack is free to move.

The engine does crank at a good rate. How do you check the glow plugs are getting power? Can you tell me where to find and check the stop solenoid? Thanks
 
   / Bobcat CT 235 Not Starting #12  
The glow plugs on my ct-445 had a light on the dash that cycled. In cold weather turn the key back off and let in cycle a few times and it started better.
 
   / Bobcat CT 235 Not Starting #13  
The glow plugs (one per cylinder) screw into the top of the engine. There is a "buss bar" that connects the tops of all the glow plugs which gets current from a wire at the back end. When you turn the key ON the buss bar should be powered with (about) 12 volts until 20 sec (or so) after the dash light goes out or after the engine cranks. The voltage will probably be more like 11 volts because the glow plugs pull a lot of current (amps). You can measure the voltage from the bus bar (or the top of any plug) to chassis ground. The plugs should be energized when the glow light is on and also while cranking. There is a glow controller that controls the dash light and powers the relay that feeds the plugs but a good dash light doesn't guarantee power to the glow plugs.

You can probably test the stop solenoid by ear. This solenoid should retract with a very audible "CLACK" when you switch the key ON and produce a similar sound when you switch the key OFF when the stop solenoid extends (which forces the injection pump rack to the zero-fuel position). If you don't get the OFF sound when you turn the switch OFF after cranking, the stop solenoid probably "dropped out" at some point, which would prevent starting. The stop solenoid requires continuous power from the key switch to remain retracted so any power interruption would cause it to extend (drop out) and shut off fuel. Some people have physically removed (unbolted) the stop solenoid to be sure it is or isn't the problem. Bu the way, if the stop solenoid is preventing you from starting the engine, the actual solenoid is probably not the cause. Stop solenoid problems are usually caused by the relay that controls the "pull" current to the solenoid.
 
   / Bobcat CT 235 Not Starting
  • Thread Starter
#14  
I have taken the fuel solenoid out. When I turn the key on the solenoid does not retract. I removed the solenoid and check to see if it was getting power, it was getting 9 volts. I was under the impression if I removed the fuel solenoid that the tractor might start. It did not. I guess I will purchase a fuel solenoid and try it.
 
   / Bobcat CT 235 Not Starting #15  
The ground path for the SS is through the case. The SS will only function if the case is touching bare metal of the engine (or a wire connects it to the engine). So check it again with the SS touching the engine block.

By the way, even when the SS won't function, the cause is usually the relay. Actual SS failure is rare.

If you have good voltage to the glow plugs and good cranking speed but no start with the SS removed, it's time to check for a jamed injection pump rack
 
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   / Bobcat CT 235 Not Starting
  • Thread Starter
#16  
Ritcheyvs,

You are spot on! I checked the solenoid the way you explained and it worked. Can you tell me how to check for a jammed injection pump rack?

Thanks
 
   / Bobcat CT 235 Not Starting #17  
The short answer is that you remove the "oil fill" plate (on the right side of the engine below the injection pump) and check to see if the injection pump rack is jammed or if it moves smoothly. Do this with the stop solenoid removed or energized (plunger retracted) with the switch ON.

You should be able to move the rack by pushing on the "pin" with mild finger pressure.

Before you dive into this, read up on the sticky at the top of this Kioti owner-operator section. Specifically look at the linked matrix , especially neches tutorial on the IP.

What is the build year of your tractor? The IP gear failure problem was most common in 2005-2008 models. If you browse around that table, you'll find cost-effective ways to fix broken IP gears if that's your problem. FYI, Kioti only sells whole IPs (for like $1K). Several owners saved a lot by just replacing the bad gears, either DIY or by local Diesel shops.

I assume your glow plugs checked out OK. If not, check them before opening the engine.
 
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   / Bobcat CT 235 Not Starting
  • Thread Starter
#18  
Thank you very much, you have been very, very helpful.

The tractor was manufactured in 2008.

How do you check the glow plugs? I turn the key backwards and the glow plug light comes on. I am sure that there is more to checking it than that.
 
   / Bobcat CT 235 Not Starting #19  
..The tractor was manufactured in 2008. ..
How do you check the glow plugs? I turn the key backwards and the glow plug light comes on. I am sure that there is more to checking it than that.

A 2008 model may well have the IP gear tooth problem. In case you don't know, you need to determine the "build year" from the serial number (not when it was bought). Typically, tractors on a dealer's lot were built 1-2 years prior. I don't know about Bobcat but the first digit of the serial number indicates the build year for Kioti.

The glow light on the instrument panel is just to advise the operator when the plugs should be hot enough to crank the engine. The actual glow plugs are independent of the light; they may or may not be powered when the light is on. As I mentioned in post 13, you need to connect a volt meter between the top terminal of one of the glow plugs (or the connecting buss bar) and chassis ground. Then verify the plugs are actually get power when you turn the switch to ON and also while you crank the engine. Unless you have a voltmeter with very long wires and alligator clips, it helps to have an assistant to turn the key while you hold the connections and watch the meter (or vice versa). You should see something in the 10-12 volt range if all is well. If the glow plugs are cold the engine probably won't start.
 
   / Bobcat CT 235 Not Starting
  • Thread Starter
#20  
I hooked up the meter on the glow plug buss bar. When I turn the key backward to activate the glow plugs I get approx 11 volts. When I try to start the tractor I get 0 volts
 

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