520h hydro temp issue

[Adams94 1,068]

I am having an issue with a 520 I just bought a few weeks ago.  After about 30 min of mowing my hydro temp light comes on. I took the fender off this morning and cleaned it really well with a blow gun but no change.  Oil level is ok.   I think I may change the oil in the hydro.  But any other ideas

[littleredrider 409]

Does is feel hot to the touch? I have a diesel on mine, was using it pretty hard the other day, and was barely warm to the touch. Change fluid/filter with the right stuff, (there is a right n wrong!) and go from there. 

[Adams94 1,068]

2 minutes ago, littleredrider said:

Does is feel hot to the touch? I have a diesel on mine, was using it pretty hard the other day, and was barely warm to the touch. Change fluid/filter with the right stuff, (there is a right n wrong!) and go from there. 

I haven’t touched it honestly.  Just gave it a cool off time, didn’t want to hurt it.  Suppose to be 10w30 oil right?

[littleredrider 409]

I believe so yes. I had to do a search to find right oil n filter lol. 

[Adams94 1,068]

Just now, littleredrider said:

I believe so yes. I had to do a search to find right oil n filter lol. 

I’ll do some digging lol

[roadapples 6,983]

10-30 oil.  1410 NAPA filter

[squonk 41,328]

Get some GUNK engine cleaner. Remove the seat pan and go to town. Get all the fins clean. Use Mobil ! oil.Make sure the plastic fan isn't missing a blade

[BOB ELLISON 2,981]

I use 10w30 mobile 1 synthetic in my c160.

I know the sandstrom is different than your Eaton 1100 but I use mine mainly in the winter with no hesitation .I can start it and go.

[1995 520H+96+97 937]

Is the white plastic fan, bolt and washer there?

[Pollack Pete 2,273]

I hate to repeat,but like others have said,10W30 Mobil I full synthetic.Use it in all my later model hydro's.I prefer a genuine Toro  tranny filter.So far......so good.

[Adams94 1,068]

53 minutes ago, squonk said:

Get some GUNK engine cleaner. Remove the seat pan and go to town. Get all the fins clean. Use Mobil ! oil.Make sure the plastic fan isn't missing a blade

Yea I’ll get it washed good I guess.  The fan is all there.  Just got done mowing with it and the hydro and even the filter are hot to the touch, maybe not burn you hot but I wasn’t keeping my hand on there.  Never done the same with my 195 after working it

 

54 minutes ago, 1995 520H+96+97 said:

Is the white plastic fan, bolt and washer there?

Yea all look good

[formariz 11,988]

Could be something wrong with sensor also. I switched to a gauge so this way it can be monitored accurately. Its pretty interesting on what causes temperature spikes or for it to rise. Outside temperature has a lot to do with it also. With gauge you can tell if it is going to the point where it will break down the oil which is I believe 250F. On a hot day mowing for over an hour mine never passed 160?

[pfrederi 17,866]

FWIW  The temp gauge WH use on the D series (Sunstrand) Showed white 100-200 then  yellow from 200 to 250 then Red

[EricF 589]

Might sound like a silly question, but is the plastic fan on backwards? Try taking it off and flip it around, see if you get better air flow over the hydro unit's fins.

[lynnmor 7,354]

Grab the plastic fan and see if you can turn it by hand, I had one slipping although the bolt felt tight.  They used red Loctite on the bolt making it fell tight but had almost no pressure on the plastic fan.  That is the only time the temperature light ever came on and the transmission sure was hot.

[Adams94 1,068]

2 hours ago, lynnmor said:

Grab the plastic fan and see if you can turn it by hand, I had one slipping although the bolt felt tight.  They used red Loctite on the bolt making it fell tight but had almost no pressure on the plastic fan.  That is the only time the temperature light ever came on and the transmission sure was hot.

I will do that

 

4 hours ago, EricF said:

Might sound like a silly question, but is the plastic fan on backwards? Try taking it off and flip it around, see if you get better air flow over the hydro unit's fins.

I thought about that. I may try that as well

 

4 hours ago, pfrederi said:

FWIW  The temp gauge WH use on the D series (Sunstrand) Showed white 100-200 then  yellow from 200 to 250 then Red

I like that idea

 

4 hours ago, formariz said:

Could be something wrong with sensor also. I switched to a gauge so this way it can be monitored accurately. Its pretty interesting on what causes temperature spikes or for it to rise. Outside temperature has a lot to do with it also. With gauge you can tell if it is going to the point where it will break down the oil which is I believe 250F. On a hot day mowing for over an hour mine never passed 160?

Where did you mount your gauge. I did work my c195 this afternoon on the 3 point disc for prolly half hour.  And the filter felt just as hot as the 520 so I’m kinda wondering if a new sensor would help

[formariz 11,988]

1 hour ago, Adams94 said:

I will do that

 

I thought about that. I may try that as well

 

I like that idea

 

Where did you mount your gauge. I did work my c195 this afternoon on the 3 point disc for prolly half hour.  And the filter felt just as hot as the 520 so I’m kinda wondering if a new sensor would help

[N875ED 98]

One member above suggested reversing the fan (or more specifically checking to see if the fan is on backwards.)

 

Reversing the installation of any fan on a rotating shaft does not change the direction of airflow. Based on the blade geometry, the flow may be different (less flow, since WH would have installed the fan for max airflow) but it still moves air in the same direction.

[EricF 589]

On 5/26/2020 at 1:45 PM, N875ED said:

One member above suggested reversing the fan (or more specifically checking to see if the fan is on backwards.)

 

Reversing the installation of any fan on a rotating shaft does not change the direction of airflow. Based on the blade geometry, the flow may be different (less flow, since WH would have installed the fan for max airflow) but it still moves air in the same direction.

That's exactly it. One orientation or the other will move air, but one direction will tend to generate a better, stronger flow of air. The hydro unit is buried under the fenders and between the side covers -- there's plenty there to restrict air flow. Find the fan orientation that works best.

 

If you check the parts diagrams available here on Red Square, you'll find the fan installation illustrated. Make sure the fan blades are oriented exactly like the illustration to get the intended performance out of the fan.