Kohler K-series engine temperature

[FUTZ]

How much did you end up paying? I won't tell nobody...like

[Eugen]

It was 25.43 free shipping.

I had explained to my dear how important it is for the tractor not to overheat and catch fire as the husband is useful around the house unburned. She agreed.

Nevertheless when the item arrived and the oldest asked what did daddy get she said "daddy got a new toy" so much for being taken seriously in this house

[DavidBarkey]

The do hickey has been installed. Temp sensor between the head and spark plug.



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Did some work with the tractor. The temperature stabilized at 312.8F or 156C. This is the loader tractor, 644.

A lot of the older air cooled engines had less tin work for air flow . So some may run hotter than others . Knowing that I am curious on what the oil is running at , at the same time.

[propane1]

Get the cookware out Eugen. And you could cook supper while your using the tractor.


Noel

Maybe I make cookies

Seriously now, unless someone else can prove otherwise this temperature at the spark plug is perfectly healthy.

By the way I checked timing with the ohm meter and points and the mark on the flywheel, it seems fine.

Ok. Thanks. I’ll stop asking

Noel

[propane1]

Ok. So at 312F at the spark plug. What do you's think the top of the aluminum piston temperature is ? Is it less, or more. ?? And. I don’t know this for sure. Some of you may. When you weld aluminum with rods, what ever they are. I’ve seen that you get the aluminum to 400 F to weld to. Aluminum head and piston must be getting a bit soft at over 300 degrees Fahrenheit. Just my thinkin. I don’t have any facts !!!

Noel

[Eugen]

Couldn't find much info about the temperature at the spark plug on garden tractors, but this is a topic that has come up fairly often on air cooled motorcycle engines, and they also use aluminum heads. Here's what someone said in response to the question if 200C at the plug is too hot.

Generally higher revs will run hotter, as there is less time for cooling between power strokes. I glanced back at some testing earlier, we tortured one engine to plug temps over 300 degC. That was extreme, but like I said, 240 degC is about the lowest temperature I've ever seen an engine get unhappy with. Many will run thru hundreds of hours of durability in the mid 200's without issue. You are worrying a lot about nothing.

The same guy mentions oil temperature too. He seems to have been a tech of some sort

The temps I've been talking are definitly C and taken via thermocouple ring under the spark plug. I pulled a few rounds of data up last night and see where one torture test had a bike up to 310 degC at the plug, and 150 degC oil. Now THAT is hot. 250/130 are more common temp limits, again, depending on the engine.

He's talking about reasonable limits being 250C which is almost 500F, for head temperature on the plug, and 130C or 266F for oil.

Is there a reason why this would not apply to the Kohler?


Well, reading that thread over at the motorcycle forum is hilarious! Listen to this

This is akin to worrying about your teenage daughter's sex life. It may get hot at times and you're better off NOT knowing about it… as long as nothing gets damaged from that hot piston banging around in there at high revs.

So I'll just be thinking about aluminum frying pans getting weak at 350F. Or I ask

[DavidBarkey]

Depending on the engine , and how they are or are not shrouded /and or fan cooled . Rpm can make a difference.
example ; sitting idling a dirt bike for extended period of time will cause over heating as they need the bike to move for cooling as they do not have fan.
Lower rpm on some fan cooled will cause them to over heat due to the heat having more time to soak into the intake preheating the air fuel mixer reducing any cooling coming from the air charge . also these engine typically need a higher rpm for the fan to produce enough air flow for proper cooling . This is why lugging an engine at lower rpm cause them to over heat . Creating much more heat but much less air to get rid of it .

Ever notice that mower hand books tell you to cut at full speed , it is not just about the tip speed of the blade but also about the power band and cooling engineered into it by the engine manufactures.
Notice the difference between the fan and shroud on a "3600" rpm engine and a "1800" rpm engine .

[Eugen]

Ok. Thanks. I’ll stop asking

Noel

It's a good think you asked me repeatedly. Some things that you guys recommend I'm not able to do right away because I don't get enough time away from work, chores, or the kids, but eventually I do. Also it took me a while to find a way to clean up the flywheel through the little peephole. Used a wire brush from my dremel tool mounted on the cordless drill. Another complication was that whoever worked on this 644 before, routed the exhaust pipe straight down from the Kohler engine, and right over the points cover. Had to make a really tiny screwdriver to take the points cover off. Don't ask how much I had to fiddle to put it back on . Eventually I succeeded.

In my opinion the spark plug on this machine is still on the white side, so I'm thinking it's running a little lean and I need to do a little more adjustment on the carburetor.

Now, back to the temperature. I'd like this thread to be a good exploration of engine temperature for the Kohler k-series engine. It would be great if we got more data from other people as well, but as much as I can I will report my findings. I have two tractors using the K321 14HP engine, one on the loader and the other on the 444 that I use for mowing. If only i could find my other thermocouple wire thermometer to check the oil temperature inside the dipstick.

@Propane57 I've been reading quite a bit on the net about heat on air-cooled engines and at what temperature aluminum gets weaker. I could find no references to temperatures lower than 500F. Of course I'd like the head of the engine to be cooler, but perhaps up to 350F is not really concerning. It would be really nice to know what temperature you have on your spark plug on your Kohler.

[propane1]

Ok. Thanks. I’ll stop asking

Noel

It's a good think you asked me repeatedly. Some things that you guys recommend I'm not able to do right away because I don't get enough time away from work, chores, or the kids, but eventually I do.


Sorry Eugen. I didn’t mean to be annoying you, but I was just foolin with ya. But I know they run hot if timing is late. And was wondering.

Noel

[propane1]

First time this plug has been out of the Case 224 since I got it. One year next month. So, I cut some grass last year. Moved some snow last winter and has been cutting all the grass this season. This tractor sat outside for 5 years, not been used, before I got it. This plug is the one that was in it when I got the tractor.

Noel