[bolens_kid]

When I run my HT23, it heats up, but then when I want to shut it off it does not want to shut off, It makes a couple more revolutions until it does shut off. It helps a little when I let it idle for atleast a minute. What could this be? I fine tuned my carb and put my idle screw down, but it still does that. I set my idle for 1000 rpms, is that to low? Any suggestions would be great. My key ignition is original, could this cause it not to shut the 12 volts off immediately going to the coil when I shut off the key?

 

[OldBuzzard]

Sounds like you have a carbon build up that's getting hot and making the engine diesel until it cools off.

The big clue is that it doesn't happen if you wait for the engine to cool down a bit.

 

[bolens_kid]

How could I fix carbon build up? Also, is 1000 rpm to low? can I turn down the idle anymore to help with it? Because I could let it idle at 700 rpm so that when I shut it off it wants to shut off easier.

 

[79ht-23]

mine does that when the air filter is clogged up as well. meaning it's gettin more fuel than air? but what old buzzard is saying too. you have to take the heads off per the maintenance at certain intervals and clean any carbon build up. those engines run hot it seems more than others i've had.

 

[BOLENSBOY60]

sounds like your dieseling- are you using alcohol gas? they did not have that when your tractor was built- I never use ethanol gas in my equipment- I ALWAYS run my equipment at just above idle for at least 5 full minutes before I shut it down -lets the machine cool down -newer engines have that fuel shut off soloniod on the carb to prevent deaseling- for carbon build-up- you might want to try marvel mystry oil in the fuel-

 

[bolens_kid]

So today when I was running it with the moldboards, I put some fuel in it and I dumped some Marvel Mystery oil in it. I will start letting them idling down for at least 5 minutes like Bolens Boy and will keep a tradition of running Marvel Mystery oil in it. Is there any other mixtures I could add to the gas to help?

 

[hankll]

Add some SeaFoam, it is supposed to help alot with carbon......cleans it up over time or you can dribble some down the throat of the carb while running at a medium speed and adding just enough to not kill it.....it will begin to throw out a lot of black smoke, while at the same time trying to die.....but just ease up and let it catch up......it should help it.....maybe enough you won't have to yank the heads off it just yet.

 

[bolens_kid]

Thanks, I will try to get some today. Would it harm to do Marvel Mystery oil and Seafoam at the same time, or should I just do one at a time?

 

[ed-nh]

I use Marvel oil, Lucas top end oil and startron in all my tractors fuel. I mix it into my 5 gallon gas cans. Running it like this for year now and so far so good. I think that running a small amount in the gas all the time helps keep things clean as well as adding a little extra lubrication whereas gas today does not contain the lead that was needed for the valves.

 

[bolens_kid]

Thanks everyone for the suggestions. I will get some Seafoam and try doing that, and will continue running Marvel Mystery oil in the gas. Then next time I am at the parts store, I will get some other mixtures that ednh suggested. What could cause this carbon build up? I am young so this tractor will not go 4 days without being ran. I thought carbon buildup is when a tractor sits for a long time?

 

[hankll]

Normal by product of combustion, and somewhat to do with hard work, i.e., engine doubling down on a good hill or pulling a plow, etc. Not a bad thing as all engines usually have a carbon cleaning schedule after so many hours of use. And it gives you a chance to check your bores for any scuffing. too.

Oh, btw, it could also be if you have any oil blow by going on.....any slight oil burning will produce a fair amount of carbon buildup, also....

 

[bolens_kid]

I run a drop of 2 stroke oil in my gas to help lubricate the cylinder head and prevent from my exhaust from rusting out, could this be a factor with carbon buildup? The previous owner Sid this for many, many, many years and never had a problem. Also I do a lot with the tractor, I have a Johnson loader on it and am usually pulling a large York rake or a Brinly moldboard behind me on the 3 point hitch.

 

[ljohn6]

Now some may disagree with this but I will put it out there it's a old trick we used in the auto industry back in the 70's for carbon I have done this for years and never damaged a motor yet while running at operating RPM and your air cleaner lid off, take a bottle of water and drip it into the carb not enough to kill the motor but enough to slightly drop the RPM what you are doing is steam cleaning your combustion chamber and also check your timing and point gap if they are off you will get pre ignition.