One thing I noticed when doing my coolant change the other day. When I was trying to "bleed" the system, I did my fill up. After fill up I did open the petcock on the engine block until I got a good flow of pink. Just to help ensure it was all premix in there not just water. Started the engine, and allowed to get warm. Also with engine running I again bled down from the petcock to again ensure only coolant. This action maybe allowed an additional pint of fluid out. But I felt better knowing i have a full charge of actual coolant, Anyway ran the engine at what sounded like fast idle (maybe 1700 or so RPM), and waited until I saw coolant flow in radiator. Though oddly upper rad hose never got really "hot" to touch. I did put a thermometer in the rad neck and only max saw about 160. When I do this on a car, I usually see close to thermostat rating at this point. In any case I ran it about 20 minutes like this until no bubbles were present, made sure over flow tank was at level and reinstalled rad cap. Ran the unit around, next day cut grass and noted after the system had pressurized and upper hose was quite hot to touch. Indicating to me proper thermostat operation. Bottom line I'm thinking it's likely fine and I was seeing the result of the bypass allowing flow through rad while I was bleeding. And given it was running at fast idle hood up the engine was never going to become warm enough to allow flow through the t/stat. Bottom line only wondering if perhaps I should think about installing a new one or not? Machine is a 2005 IIRC and no one has touched the bolts on the housing ever. Runs like a top.
Thermostat
- Thread starter lmichael
- Start date
Running a diesel without load will not generate high internal temperatures so the coolant will not get hot. Also if the thermostat has a bypass then you'll see coolant at the radiator top. When you put the engine under load, it got hot. Get an infra red thermometer and measure the temperature at the thermostat housing or the neck of the radiator if you are concerned. If those temperatures are normal I would say your thermostat is fine.
Yeah, I think I will do that. I've had an IR thermo for a ling time. It's handy in the kitchen. Helps me not over heat non stick pans.
Do not replace thermostat unless you're SURE it is absolutely not working. Did this once on one of our cars and stripped one of the bolt holes (aluminum).
In my lifetime I've replaced countless t/stats. Never once stripped anything aluminum or iron. Sorry you had a bad experience
Pau7220
Well-known member
Equipment
L3650 GST, Landpride TL250 FEL w/ Piranha, 6' King Kutter, GM1084R Finish
Thermostats last anywhere between 5 and 30+ years. How much risk are you willing to take for such an inexpensive item. I had a stuck one cost me a tear down on a Honda 4514 because the rocket-scientist engineers put the temp sensor in the radiator, instead of the head or block where it belongs.
50+ years of changing 100’s of automotive thermostats and I can’t remember ever stripping any threads. If it does happen, that’s what Heli-Coils are for.
50+ years of changing 100’s of automotive thermostats and I can’t remember ever stripping any threads. If it does happen, that’s what Heli-Coils are for.
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I used to have a 4514. Good little machine. When I found my G2160 I could not pass it up. I actually kinda wish I had kept the 4514 as well as the Kubota. Guy can't have too many tractors 
Pau7220
Well-known member
Equipment
L3650 GST, Landpride TL250 FEL w/ Piranha, 6' King Kutter, GM1084R Finish
I still have the 4514, three 4518’s, and a 4120. All run like new.wish I had kept the 4514 as well as the Kubota. Guy can't have too many tractors
My son buys up the 18’s for a song when the CDI boxes fail… I cut them apart and re-solder the circuit boards… JB Weld them back together and they fire right up!
They're actually pretty sweet little machines. I really do regret not keeping it sometimes. I really love the Kubota and the "music" that little diesel makes (sounds like a mini CumminsI still have the 4514, three 4518’s, and a 4120. All run like new.
My son buys up the 18’s for a song when the CDI boxes fail… I cut them apart and re-solder the circuit boards… JB Weld them back together and they fire right up!
) but using that huge 60" deck in my front yards is like trying to use the Queen Mary on a small lake The little Honda with the 42" deck was perfect. Tight radius and smaller deck worked great on the front. Blades were outrageously expensive. I can buy a whole set of new blades for my Kubota for the cost of one blade for the Honda! But, yeah sweet little machinesA couple photos of my Honda also showing my oil pressure and tach setup
Pau7220
Well-known member
Equipment
L3650 GST, Landpride TL250 FEL w/ Piranha, 6' King Kutter, GM1084R Finish
Sweet. This was after the engine repair on the 14. Both the 14 & 18 have new paint.
And before the other two 18’s were added.
And before the other two 18’s were added.
Yeah, I kinda forgot about how diesels operate. How when idling they really don't heat up. The last 2 days I was working the machine pretty hard with yard work, (mowing, spraying and the like) and I noticed when I popped the hood to check at the end. Upper hose was quite warm and pressurized. I could not get that to happen without loading it up. Anyway it's all working just fine.