JD X485 Overheats fast when mowing

[Liquidsilver]

Was that the JD X485?

Nope. My old Kubota M5400. I didn't mean to insinuate that it was in a John Deere. Sorry about that.

 

[ruffdog]

I blow out my radiator (JD X744) every time I mow. I use a blow gun wand and blow from the engine side (reverse flow direction). Use a mirror and light to check if you can see through the radiator...if you can't see through it, air can't get through it. It seems for driving around, the cooling system can keep up with the heat generated but not with the extra work from mowing.

 

[Richard001]

Hey, if this is the case, oldnslo is on the spot. Overheated engines rarely cool quickly. Confirm real or false overheat, then chase the electrical side if it is not a real overheat.

Best,

ed

I agree with dirtoys. I assume that the deck is engaged buy an electric clutch. I would suspect some poor ground connections.

You will need to check all of you grounds, including the one from the battery negative.

Richard

 

[dj1701]

I blow out my radiator (JD X744) every time I mow. I use a blow gun wand and blow from the engine side (reverse flow direction). Use a mirror and light to check if you can see through the radiator...if you can't see through it, air can't get through it. It seems for driving around, the cooling system can keep up with the heat generated but not with the extra work from mowing.

My Kubota BX2680 overheated. The radiator was packed with **** the debris screen did not stop. Now I blow out the radiator every time I clean the screen. Lesson learned.

Dave

 

[se0607]

UPDATE: Since my last post I checked all the grounds, fuses, and electrical connectors. I cleaned them all with electrical component spray, but they really weren't corroded. Then the mower wouldn't start. It tried but backfired louder than ever during several attempts. So then I went and spent $100 on the maintenance kit and replaced the plugs, (which were soaked and one actually fell apart,) replaced the air cleaner and prefilter, changed the oil, (yeah, I may have spaced out during the pandemic and didn't change it for a couple years,) installed new oil filter and new fuel filter. It started right up! Still, the temp gauge pegs on red after a minute of mowing, then quickly retreats when I shut mower off.

Still, I think it is actually overheating somewhat because the hood is hot and so is the engine compartment when I raise the hood. (More than normal for a sunless 70 degree day.) I haven't done the test with the radiator cap off to see if the coolant is moving, but I will tomorrow. Honestly, I have had this machine for 17 years and it's taken a lot of punishment so I am starting to feel the itch to get a newer machine. I also think the deck itself may be the issue. Can you lube inside that gear box? I couldn't find a way to do that, but I may have overlooked something.

I will report back again for those of you tuned in to my tale of woe. Thanks guys.

 

[se0607]

My Kubota BX2680 overheated. The radiator was packed with **** the debris screen did not stop. Now I blow out the radiator every time I clean the screen. Lesson learned.

Dave

I blew it out 3 times already and used a garden hose. It's really hard to get at and I can't see an easy way to remove it or even expose it more. I don't see and mud in there, but i will maybe go out after dark and shine a light through it. Thanks

 

[LittleBill21]

its almost impossible to overheat a motor in 30 seconds. take the deck off, and engage the pto, does it still overheat? get a temp gun

 

[beenthere]

Can you lube inside that gear box?

Nope, sealed up, I believe.

Myself, I wouldn't be running water on the radiator as has been mentioned. Just makes mud, which then dries and cakes hard.
If you can't see light through the cores, suggest removing the rad and taking to a rad shop for cleaning outside and inside.

Wish you well in finding the cause, but think the clue to the cause is the "cool down" finding/result you have noted soon-after switching off the mower deck.

 

[Tomtint]

I honestly don't know the configuration of your mower let alone the cooling system..But maybe its a thermostat issue or water pump issue ?

 

[lpakiz]

On an overcast day or inside a building, place a trouble light in behind the radiator, next to the fan blades.
Then look in thru the rad from the front. You should be able to see significant light thru the core. If there is an extra cooler there, get that out of the way. I have seen (on semis) where there is a virtual BLANKET of fuzz covering the core, but you can't see it because of the extra transmission cooler. Bottom line is you MUST be able to see light thru the core, or it's impaired.
Also, grab a fan blade and see if you can roll the engine over with it. If you can't, the fan may be turning, but not full speed. At full engine speed, the fan should roar or "buzz."