hello JD Driver... the old solenoid measures 0.6 on A to B. and 11.5 on A to C. on my meter set at 200 ohms. The new Solenoid measures 0.7 on A to B, and measures 31.5 on A to C!!!!! whats that tell me???? i got a chinese solenoid?? when i get a non rainy day Ill start to pull the cowl off and might check the relays and thermistor
hello JD, Driver, I got the new switch in and started the tractor up...but when i turned the key off, the tractors idle went down, but it didnt shut off. I had to throttle the idle lever to the minimum, to stall the tractor!..I have a video, but its MP4 and apparently thats not allowed here....dont know how to change it...
The safety system on this tractor relies on being able to shutdown the engine at any throttle speed by removing power from the fuel shutoff solenoid, so it wouldn't be very safe to operate it without this feature.
When power is removed from the fuel shutoff solenoid, the actuator rod is forced out of the solenoid and into the pump by a spring. It sounds like the spring inside your solenoid valve may not be strong enough to overcome the force needed to completely shutoff fuel flow at the pump. I measured 4.8 lbs of spring force on an operational solenoid with a digital scale.
I'm having the same problem I think. So I just picked up a 99 4500 and its not starting, it just cranks and cranks, so I pulled an injector line off to see if I was getting fuel an I was not. so that's when I found out about the fuel solenoid, so I replaced it with one from Deere, and its still not starting, is the solenoid supposed to pull in on its own or not? if i apply a tiny amount of pressure to it in works when I turn the key "wile out of tractor" put it back in and nothing. is it possible that the spring inside the injector pump is getting too week for it to work and I need a new injector? can someone sell me what I should be getting for volts or oms from the pull feed when I turn the key?
The fuel shutoff solenoid has a pull-in coil and a hold-in coil. The fact that applying a small amount of pressure to the plunger on the fuel shutoff solenoid with the key turned on is required for it to retract makes it possible that the pull-in coil is not being activated.
There are lots of threads discussing the fuel shutoff solenoid circuitry. You could start by replacing the K3 Fuel Shutoff relay, and if that doesn't fix it, you will probably need to replace the "thermistor".
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It sounds to me like the solenoid has a non serviceable seal to prevent the oil from getting in it. I assume that seal is failing and causing the problem.
He said he just replaced the fuel shutoff solenoid. Are you saying you think the new fuel shutoff solenoid has a bad seal????
I was referring to the original OPs problem of the solenoid getting oil behind the plunger. Somewhere the discussion took a turn towards electrical. While that might cause the plunger not to get a proper signal the problem of oil preventing it from retracting is not electrical in my opinion.
It is probably more likely that area of the injection pump is sealed from the oil supply and that seal is allowing oil to get to the solenoid.
before I start tearing into the tractor where would I find the thermistor?
Not sure since my 4610 does not use this part, but maybe someone who has replaced one on a 4500 or other 4X00 tractor will respond.
You can pull the relay and test it with a multi-meter first before replacing if you like. Power initially flows through relay pin 30 to pin 87A and then to the PTC (thermistor). After the PTC warms and opens, the K3 relay energizes and switches the relay wiper to pin 87 to open the pull-in coil circuit (and reset the PTC). If the un-energized K3 relay has low resistance between terminals 30 and 87A, it should be fine to activate the pull-in coil (if the PTC (thermistor) is good).
You can also energize the relay by applying 12 Vdc across relay terminals 85 and 86 (polarity not important), and make sure that there is no longer continuity between relay terminals 30 and 87A.
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