Kohler under mysterious load
 

OK, the little 122 or 124 ( I forget what it is) with the scrape blade is doing something really strange. It will be running along just fine and then suddenly go to loading the engine, a LOT. Its done it a few times. First time was right after I bought it lasted just about a minute or so, figured crappy fuel/dirt. Has done it a couple times since but it always seems to clear up--was still thinking something in the fuel. Did it again today for a rather extended time period. It happens quite suddenly, was only about 1/2 throttle. Engine goes under a terrible load doing nothing. It is NOT smoking out the exhaust. However the engine is getting so hot it seems to be smoking from everywhere, literally. I could cut the switch off and it would smooth out and try to keep running for a few seconds. almost like it was so hot it was igniting the fuel. Finally shut it off to have a look, but it was too hot (I had been running it for about 20 minutes). Didn't see anything wrong (looking at belts, PTO etc). Cranked it back up and as long as I left it idled all the way down, it ran OK, was able to make it the shed. If I gave it any throttle, it acted up. Made it to the shed after about 4-5 minutes. Before shutting down I sped it up and it ran fine for a few seconds, then began acting up. Seems to be a timing issue, but it could it be a valve? Engine was too hot to check the PTO or the generator to see if anything appeared binding. Nothing made an squeaking/squealing noises like it was rubbing or a bearing going out.
When I get a chance, I'll get it in the shop to start checking it over. You guys got any good ideas regarding what it could be?

Check the wire going to the condenser. I had one that did something similar and it turned out the wire was broke off right at the condenser and at certain rpm it wasn't making contact.

Tim, I had wondered about the condenser. Now that you mention it, I had to band aid a lot of wiring on the generator side, think most of it was removing homemade lighting. Wouldn't surprise me if the ignition wires were bad. Thanks for the idea!

Why all of a sudden go lean after 20 minutes of running? Pulling choke on will not help. What gets me is when it would clear up by itself? Probably check the wiring first as it is easiest. If nothing funny looking then open and clean the carb.

For clarity, when I say load, I mean like its under a ridiculously heavy load. I honestly thought to begin with something was binding up or piston was about to melt. Literally was expecting it to self destruct.

That’s the first thing that came to my mind John. Connecting rod starting to sieze or piston like you said. Any visible aluminum in the oil? Never seen a long dipper break off but that’s what oils everything so it could be a possibility? I would go with simple first like stated, time it, adjust carb, but getting that hot that fast is strange.

When I’ve had a bad condenser or bad condenser ground it normally sounds like a bad misfire or valves sticking and runs terrible, not necessarily an under load condition.

I would check the s/g, when it does that and see if your voltage at the battery is high like 15+ volts.

won't hurt to check the oil, may have to drain a bit and see what comes out.

I wondered if it was possible the generator or regulator somehow screwed up and was causing too much load. I'm pretty sure this one has a new belt on it, but I would have thought it would have burnt the belt up if the charging system loaded too much. FWIW, I shut it off 2 or 3 times and the starter/generator turned over just fine to crank it back up--so I doubt its anything "mechanical" regarding that. I didn't notice the amp gauge reading high when it acted up.

Kohler under mysterious load
 

I had this symptom with my 1450 for a long time. I couldn't find any posts from anyone with a similar issue. At first I thought I had an issue with the hydro drive .After going through everything I could think of I found that the previous owner had replaced the ignition coil with an aftermarket coil that wasn't correct. I had the extreme loading and heating symptoms also. After replacing the coil with an original one, I used it all last winter for snow blowing and mowing all this summer with out any problems. It took a lot of head scratching before I got it solved.
I hope this helps.

I have a 70 that did the same thing the other day while mowing.
Twice as a matter of fact.
The first time it quit, I just left it sit for a while and it started right up gain w/no issues.
Mowed for about 5-10 minutes and she died again.
This time I installed a new plug, issue is gone and I mowed for over an hour until finished.

:HeadScratch: