L3650 Overheating

[GarthH]

Well I finally got my acreage and the L3650. It is a high hourer but seems to be in great shape.

I've spent about 4 hours mowing so far and have really enjoyed working with the tractor. The big turf tires seem really good.

Anyway as I was driving home from the dealer the tractor was showing pretty hot. I had shut it down a couple times, opened the rad, checked the water temp in the rad with noting unusual to note.

Just as I was getting home the guage dropped to mid way and has remained there since.

I was mowing late on Thurday and thought I would see if the lights would help. The temperature guage immideately went off the scale showing super hot. Turned off the lights the guage slowly dropped to normal.

Seems like an problem with the alternator to me but the tractor has been keeping the battery charged.

The belt seems to be normal tension - about 1/2 inch play.

Any thoughts - maybe the temperature sending unit but if it was screwed you would think it would be more consistent.

Any suggestions?

Garth

 

[chrisjbell]

Sounds like it might be a short in the wire to the sending unit. With an electric temp guage it will read full hot when the sending wire grounds out. Just a thought...would explain why it is intermittant and seems to depend on what the electrical system is doing...

 

[GarthH]

Sorry it took a while to get back to you. I still do not have internet so my access is somewhat intermittent.

We have replaced the antifreeze at the beginning so I was guessing the high level was an air lock - I am not so sure it is.

My next guess was maybe the pump was too tight - maybe a bad bearing. I thought maybe the belt was not turning the pump properly when the alternator was engaged. I do not have any real proof of that ideal. But based on that concept I was guessing that maybe the battery was low initially so the alternator took a couple hours to charge it back up and while do so maybe the pump was not circulating properly. While I am doing yard work maybe the alternator is running after first startup but the pump would not be an issue as the thermostat is likely closed.

I do not have anything concrete to figure out why it moved from just touching the red to dropping to the mid level.

I agree with the short ideal and I will start looking for it - I thought it might be in the lights or maybe the sending unit. I will likely put a manual temperature guage on to get the real facts. I will also take a look at the pump, alternator and belt.

Thanks for your help.

Garth

 

[RobJ]

With some hours on it it wouldn't hurt to replace the thermostat.

 

[mjarrels]

MAKE sure everything is clean... my screens were clean yesterday when I was mowing but need to blow alot of junk out of the engine compartment using an air hose...

mark

 

[Farmerford]

Sounds like you determined from checking the radiator that the water did not actually overheat.

The guage movements are the symptoms of a ground problem somewhere, especially if you had the flashers on when driving from the dealer. Then when you turned the flashers off whenyou got home the gauge acted normal. The flashers are not on constantly like the lights, so they did not move the gauge as far or as fast.

When a ground goes bad on a car/truck/tractor, strange voltages pop up at different places when something that uses that ground is turned on, because it seeks a ground through other places. If your lights had a poor ground, they could have caused a current to flow through your temperature sensor circuit. Check out the ground connections, not only at the battery, but at all points in the circuit. The lights probably have a separate ground circuit that connects to the engine/chassis somewhere, and that ground may well be corroded, given the age of the tractor.

 

[GarthH]

Thanks everyone. Fairford you were on the right track. I had the tractor at the dealer installing a FEL and the tech had trouble starting the tractor. He replaced the positive battery cable and now everything is working perfectly - I didn't tell him yet that he fixed more than he knew.

I've been giving the tractor a pretty good running - likely 10 hours over the past few days. I am glad I ended up with the 40 hours - lots of abilities.

The FEL has certainly made an issue with the lack of power steering and the weight distribution. Mowing along side our 1/2 mile road I don't feel as comfortable on the angle. I've been careful to keep the bucket quite low thinking it will help the center of gravity. Over this weekend I'll figure out how to remove the loader just so I know.

I'm starting to pickup the other 3pt equipment - tiller, rake, box blade, cement mixer and snow blower. The tiller is available tomorrow so I will hopefully get the garden done tomorrow or Sunday.

Thanks again.

Garth

 

[kbota]

Sounds like you determined from checking the radiator that the water did not actually overheat.

The guage movements are the symptoms of a ground problem somewhere, especially if you had the flashers on when driving from the dealer. Then when you turned the flashers off whenyou got home the gauge acted normal. The flashers are not on constantly like the lights, so they did not move the gauge as far or as fast.

When a ground goes bad on a car/truck/tractor, strange voltages pop up at different places when something that uses that ground is turned on, because it seeks a ground through other places. If your lights had a poor ground, they could have caused a current to flow through your temperature sensor circuit. Check out the ground connections, not only at the battery, but at all points in the circuit. The lights probably have a separate ground circuit that connects to the engine/chassis somewhere, and that ground may well be corroded, given the age of the tractor.

Dead on accurate ! Excellent explanation Farmer! Grounds with resistance back to battery negative cause unbelievable weird symptoms. Remove all ground connections, clean, retighten. If that doesn't help, then try running a ground cable directly from battery negative to the engine block. Cost is only a couple of bucks, and might cure a lot of problems. I had a similar symptom once, and found the crimp connection to a ground cable was high resistance, but was constantly changing with tractor movement. I cut off the old crimp connector, cut back insulation, crimped a new connector, and then "soldered" it. End of problems...that's been years ago.



Good luck

k