G1800S Slowly Overheating and Under Performing

badninja

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Mar 13, 2018
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If I run it for too long (15 mins or so) with the throttle near all the way up it very slowly works its way up to over heating. If I throttle down near the bottom it will cool back down towards the middle of the guage after a little while. Its also been running a little rough with the throttle too low. Had some very thick grass after getting a couple weeks straight of rain every day so had to run it pretty hard to get anywhere. (This is my first diesel, suggestions on what to look into to get it running ideal again would be appreciated)

If I run it til it gets near the top of the green and then shut it off(about a quarter inch or so away from the end of) still well within safe operating temp, water will start boiling out of the overflow.

Its not low on water. Its right where it should be. Is this a bad thermometer? Or what else should I look into?


As far as under performing, as mentioned its not doing well at low to mid range throttle. Seems any bit of thick grass will slow it down and make it blow a bit of smoke(black). Also simply going up a the bank of a steep ditch is giving it trouble as well where it didnt before. Im not real familiar with diesels and dont really know where to start to fix this problem. I wouldnt know if this is something as simple as adjusting a screw or adding some fuel additive or if its more along the lines of a tune up or maybe a bad injector or something..

Thanks
 

shiftsuper175607

Lawn Addict
Joined
Sep 11, 2013
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1,000
If I run it for too long (15 mins or so) with the throttle near all the way up it very slowly works its way up to over heating. If I throttle down near the bottom it will cool back down towards the middle of the guage after a little while. Its also been running a little rough with the throttle too low. Had some very thick grass after getting a couple weeks straight of rain every day so had to run it pretty hard to get anywhere. (This is my first diesel, suggestions on what to look into to get it running ideal again would be appreciated)

If I run it til it gets near the top of the green and then shut it off(about a quarter inch or so away from the end of) still well within safe operating temp, water will start boiling out of the overflow.

Its not low on water. Its right where it should be. Is this a bad thermometer? Or what else should I look into?


As far as under performing, as mentioned its not doing well at low to mid range throttle. Seems any bit of thick grass will slow it down and make it blow a bit of smoke(black). Also simply going up a the bank of a steep ditch is giving it trouble as well where it didnt before. Im not real familiar with diesels and dont really know where to start to fix this problem. I wouldnt know if this is something as simple as adjusting a screw or adding some fuel additive or if its more along the lines of a tune up or maybe a bad injector or something..

Thanks

You could pull the thermostat and put it in a pot of water and heat...see if it opens.

If you go to all the trouble to remove it...put in a new one.
Cheap expense compared to a new mower.
Fresh anti-freeze at 50/50 might help also.

make sure water pump is working...start when cold...cap off and watch for circulation...of course thermostat has to open...so a catch 22...maybe replace thermostat first.
 

jp1961

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Joined
Jul 22, 2013
Threads
39
Messages
785
Have you taken a hose and cleaned the external radiator fins? There also should be a removable screen than can get clogged with debris, rinse that off too.

Check the condition of the air filter too.

Is the fan belt reasonably tight?

Have you ever run the tractor out of fuel? If yes, another item to check is bleeding the fuel lines, I've never done it on my Kubota, but did on a Yanmar 2 cylinder diesel. Bleeding the lines is done while the engine is running by slightly cracking open the banjo fitting at the injectors. If it's still not running right after checking the above, I'd take it to a Kubota dealer.

If you've never bled diesel injectors, start the engine, using a box wrench open the bolt at the banjo fitting a slight amount, maybe a 1/4 turn and let the diesel fuel along with trapped air escape then tighten it. It shouldn't take more than a few seconds. You're just purging the system of trapped air.

Regards

Jeff
 
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