6441 hard to start

[cul8ter6969]

I recently purchased a 6441 and it is hard to start. One issue is the glow plug light is not coming on at all when I move the key to position 1. If the tractor is in the sun and the air temp is over 60 is will usually start, sometimes I need to jump it with my truck and it takes the extra power to turn it over. The battery is less than 6 mo old according to the dealer I bought it from. I noticed something is draining the battery when the tractor is off (possibly a bad relay, need to troubleshoot further). Could the glow plug light issue be the glow plug relay/controller that is bad? I checked all the fuses in the cab but also just learned there is another fuse near the glow plug relay/controller I also should check. I just wondered if anyone else had been down this road with this tractor.

 

[BertZegers]

I don't have a 6441, but I have the manual and the electric diagram is not in there.
The manual states that if something is wrong with the glow-system the glow light blinks.

If I had to trouble shoot this. I would start with checking if the glow plugs get voltage. This is easily done with a voltmeter or 12 volt test light between ground and one of the glow plug connections.
Voltage should be present (shortly) while the key is turned to 1 if the engine is cold. If voltage is present than plugs are suspect.
If no voltage is present then I would check if glow-relay gets power from battery, check fuses.
An electric diagram would be very helpful for further diagnosing.
Ask the dealer for the electric diagram, preferably he emails it to you, so it can be posted on this forum.

 

[BertZegers]

If your glow-relay is a AEV 7022 like in the picture, than the connectors with the nuts (30 and 87) should be + from battery and glow plugs.
You can click on the image to enlarge.

In the 6 prong plug, I think not sure!,

T from temperature gauge
31 ground
L glow light
31 ground
50 from ignition, maybe position 1
15 battery + from ignition switch.

You can try to "probe" the plug at the back while connected to find out what is going on.

 

[cul8ter6969]

Thanks for the reply. Since my original post I went ahead and replaced the glow plug relay but it did not seem to help. Right after that my starter solenoid went out so I'll be replacing that this week (probably due to cranking on the engine too hard since my glow plugs aren't activating properly). I do have the relay you mentioned. A few weeks back we checked voltage to the glow plugs and at the time it was okay. I'll do some add'l diagnostics this weekend. I do have an electric diagram, I'll scan and upload when I can.

 

[Roadworthy]

If the glow plugs are getting the proper voltage you may consider they are defective. Disconnect the lead from the glow plug and check the resistance from that point to ground. It should not be zero and it should not be infinite. It should be quite low - perhaps ten to fifteen ohms.

 

[BertZegers]

Thanks for the reply. Since my original post I went ahead and replaced the glow plug relay but it did not seem to help. Right after that my starter solenoid went out so I'll be replacing that this week (probably due to cranking on the engine too hard since my glow plugs aren't activating properly). I do have the relay you mentioned. A few weeks back we checked voltage to the glow plugs and at the time it was okay. I'll do some add'l diagnostics this weekend. I do have an electric diagram, I'll scan and upload when I can.

The starter and the glow plugs are the biggest power users. Before replacing parts, make sure the battery clamps and cable ends are clean, especially the ground contacts. Check for discolored or corroded contacts or wire. A bad contact in a 12 volt system can give you all kinds of problems. A starter turning to slow makes it hard to start. I am surprised that you need to glow in Texas.