Wheel Horse 520H

[mattc 0]

Hi! i just bought a 520H with about 300 hours on it. I have only mowed with it for about one hour and the hydro temp light came on. I have read through the forums and looked at the fan and all. I do hear a little belt squealing. Would this make the temp light come on or is there maybe something else. Thanks

[rickv1957 70]

:thumbs: If oil level is full and trans works good and is clean,could be sending unit,Rick

[mattc 0]

where would this unit be?? i am totally new to this and do not have a manual. thanks for the quick response

[MalMac 1,328]

I just went through this. My light came on before the trans even came up to temp. Found out mine was a sending unit. Iwas going to tell what side its on but I am drawing a complete blank right now. I think its on the lower right side as you sit on the tractor. I have got to go look to make sure. I just remember that you can't mistake it. When you look, you will see the wire feed going to it.

[DrabHorse 1]

I have a question, what would be normal operating temp for this transmission, and at what temp causes the warning light to come on? Also just for fun, at what temp do you think would cause damage or problems?

[mattc 0]

i called the man who used to be the wheel horse dealer here in town and he said he always just disconnected the lights when they came on and he couldn't figure out what the problem was...... so i definately will be doin ALL repairs for myself! but he said that he had never seen one come back from overheating of the hydraulic temp. i am going to replace all my guages and the hydro filter and sending unit just to be sure.

[Save Old Iron 1,563]

Hey Matt

maybe one more thing to check. When I started the tear down of my C175, the fins on the trans housing were packed full of dirt. Since this tractor was acquired with a bad engine, I can't say for sure the hydro is going to be an issue because of the buildup, but its worth a look on yours.

Also make sure the fan is on the correct way - to blow air over the trans.

Check the fan blades are secured to the pulley too!

:D

[Save Old Iron 1,563]

i am going to replace all my guages and the hydro filter and sending unit just to be sure.

The sending unit is just an on / off thermal switch - when it senses an overtemp condition, a lite on the dash gets it ground connection from the temp switch closing and the hydro temp light turns on - real simple.

Take a look at the temp switch - sometimes they have an activation temperature stamped on them - you could place them in a pan of water with a thermometer and pull the sender out of the water at 50 degrees before the trip temp and ohm it out with a continuity meter. should be an open circuit - heat it back up to within 20 degrees of trip temp - measure it again - and so on until the sensor trips. compare the water temp to the published trip temperature and make an informed decision if the temp sensor is actually bad.

I'm thinking the odds are the sensor will be the culprit and not the wiring or indicator lamp circuit.

[mattc 0]

excellent ideas! I will give em a go.

[gwest_ca-(File Mod) 10,522]

If your switch is part # 113193 it is set to close at 200

[buckrancher 2,675]

i am going to replace all my guages and the hydro filter and sending unit just to be sure.

The sending unit is just an on / off thermal switch - when it senses an overtemp condition, a lite on the dash gets it ground connection from the temp switch closing and the hydro temp light turns on - real simple.

Take a look at the temp switch - sometimes they have an activation temperature stamped on them - you could place them in a pan of water with a thermometer and pull the sender out of the water at 50 degrees before the trip temp and ohm it out with a continuity meter. should be an open circuit - heat it back up to within 20 degrees of trip temp - measure it again - an so on until the sensor trips. compare the water temp of the thermometer to the published trip temp and make an informed decision of the temp sensor is actually bad.

I'm thinking the odds are the sensor will be the culprit and not the wiring or indicator lamp circuit.

If your temp sending unit checks out ok. Its a good chance it's a internal hyd. oil

leak inside the pump

could be ether a bad spot on a o-ring or a dirt particle keeping one of the

check balls from sealing up

oil being forced thru a pin hole at high pressure will get hot fast and

this will cause your over all oil temp to rise over the switch limit

and trust me you don't want to know how much a new pump is. There are

places that will rebuild your pump for you (search on line) or you can try a used one from E-Bay all eaton 1100 pumps should work from a 312H to the 520H

good luck

:thumbs:

[wh500special 2,055]

I do hear a little belt squealing. Would this make the temp light come on...

Probably not the cause, but a loose belt would make the transmission operate at a slower input speed than it might find ideal.

The fan won't move the required amount of air and the pressures needed to move the tractor against a given load will have to be higher. All this could contribute to a harder working, hotter transmission.

Do what everybody else tells you to do, but also replace your belt with a new Toro part...after you've cleaned the thing off.

Steve

[mattc 0]

Good news!!! i found out what the problem was. I removed the fender, seat, and right rear wheel and scraped, washed, blew enough dirt out of that area to, GET THIS, fill a 5 gallon bucket 3/4 the way full!!!! In the process i actually learned that the fan on the hydro pulley has had all but one fin knocked off!!! I'm willing to bet between those two things it made the hydro get hot! Does anyone by chance have a spare fan or perhaps know someone that i can purchase one from. I'd like to go through the resources here before somewhere else. Thanks for all your replies and I know see how Wheel Horses can drag you in. I recently just bought a c-110 i think it is and my wife's grandmother wants me to come look at two she has in her barn!!!!! :thumbs:

[Save Old Iron 1,563]

I removed the fender, seat, and right rear wheel and scraped, washed, blew enough dirt out of that area to, GET THIS, fill a 5 gallon bucket 3/4 the way full!!!!

I guess this makes me feel better about having a good chance my C175 with dirt filled fins will survive that experience.

Thanks for getting back to us and let us know if a good cleaning actually resolves the high temp issue. At this point we are all think how could it not !

:D

[mattc 0]

i ve used the mower for about 6 hours since the cleaning and no hydro temp notice yet! i still need to replace the fan for the hydro unit. Is the hood on the tractor supposed to be super hot because its crazy how hot it gets when its used. What do i need to make sure is cleaned really well. Im planning to pull all the fenders and covers off but is there any special parts/areas i need to show special attn to??

[Operator 7]

This is what I do to my tractors, put them on the hauler pull all the tin off I can then go to the car wash and presure wash everything I can up , under, all around anywhere I can wash. Then I haul it home and let it sit and dry off, maybe use the air hose too. I do this on the motor too. But I don't even try to start with anything wet. Works good for me. After every mowing I use air and clean out fins on engine and rear hydro.

Randy