OVER HEATING

[wlc1]

hi folks, i have been off a few weeks (no computer)8n 6v front. put both new radiator hoses and thermostat it did not have a thermostat when i bought it.bush hoged lower prasture had a ton of fun and no problems.2 weks later start it up let it warm up.hook up bush hog and engage pto.putting load on eng.antifreez shoots out radiator cap. hop off cheek cap it on right.bottom hose hot. top hose not.what should i check first?

 

[old]

First off make sure the air can flow threw the radiator it maybe clogged up with grass etc. If the fins are clean and you can see light threw it then you may have a sticking thermostat or even a clogged up cooling system

 

[DollarBill]

Top hose cold makes me question if the thermostat is opening.

Use a meat thermometer in a pan of water. Bring temp up to 180 degrees then drop the thermostat in to see if opens properly.

One other idiosyncrasy of the N's is you only fill the radiator to the point that coolant just covers the top of the flues in the radiator, any more and it will puke it out.

 

[Bruce (VA)]

The most common reason for an N to “over heat” is over filling the radiator. Only add enough fluid to cover the core. (check out tip # 24, below as well as tips 25 & 35) It is not actually over heating; it is just spewing out the excess water.

If the radiator is not overfilled, check for low coolant, a loose fan belt, debris in the radiator fins or a stuck thermostat. A bad water pump will usually squeak or leak. (If you ever have a water pump start leaking or making noise, replace it immediately. A N water pump will come apart & launch the fan into the radiator.)

Sometimes (rarely) the t-stat can migrate in the hose & get stuck closed. Or, in an attempt to keep that from happening, some owners will put a third clamp on the hose & tighten it too much resulting in a stuck t-stat. The OEM top hose came w/ a non-adjustable ban to keep the t-stat in place.

The fan belt should have 1/2" of flex at the mid-point; no more, no less.

Unless you have a pusher fan, blowing out the radiator from the engine side is always a good idea.

But, sometimes you just have to bite the bullet & flush out the block & radiator. To do that, remove the t-stat from the top hose. Then, remove the bottom hose from the radiator & stick your garden hose in the radiator. Turn the water on (reverse flush) & the water will flow into the radiator, then the block & out of the disconnected lower hose. Let it run until the water is clear. Then, check the radiator flow. Stick the hose in the top of the radiator; the water should flow out of the bottom w/o backing up in the filler neck. It should flow at 19.5 gallons a minute. As a final flush, put a gallon of white vinegar & about 2 gallons of water in the radiator, run it to operating temp & then drain it again. Don’t forget to put the t-stat back in correctly!

Use 50/50 anti-freeze & distilled water as your coolant. The anti-freeze contains rust inhibitors, pump lubricant & raises the boiling point of the coolant.
50 Tips

 

[wlc1]

would radiator over full stop top hose from not getting hot?

 

[Bruce (VA)]

No.

Did you install the t-stat correctly?

Is it a 160 or 180 t-stat?
50 Tips

 

[wlc1]

its a 160 with pointed end towards radiator