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Discussion Starter · #22 · (Edited)
Well, the little Predator stars on the first pull of the rope and seems happy so maybe I'll just leave it. I have a new plug on hand if needed. I am just gun shy of the Torch plugs. I had never even seen one till I helped that fellow figure out why his generator wouldn't start. Then my generator wouldn't start after about 30 hours of use. Not all the hours were at once of course. How long have the Torch brand plugs been out on the market? I don't think our auto parts stores carry them. They can be found on eBay I see.
 

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Stew, I’ve never heard of a exhaust pipe getting orange/red with a rich mixture. Always thought when it was a lean mixture that it could do that. Interesting.

Noel
I assume that what was happening was that with the rich fuel mixture all the fuel was not able to burn in the combustion chamber due to a lack of oxygen that was used up with the normal amount of fuel. Once the non spent fuel left the combustion area through the exhaust valve and encountered fresh air from outside present inside the muffler the hot fuel would self ignite inside the exhaust pipe where normally there would just be spent exhaust gasses - just my thoughts. Would think it would be like having a small torch heating up the inside of the pipe with the excess fuel being ignited as it entered the inlet to the exhaust pipe. Would think a lean mixture would burn up all the fuel inside the combustion area since there would be an abundance of air to fuel resulting in just spent exhaust gasses in the exhaust pipe - just my thoughts.
 

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Discussion Starter · #24 ·
I was going to razz a bit you about having fresh air inside the muffler. But I'm sure you meant it another way. Maybe I just am not reading it like you were explaining it. Sorry!! I'm just in a goofy mood today. No offense intended please!! I have had the exhaust manifolds, pipes get extra hot on a motor that the timing was retarded too far. A too rich fuel mixture will for sure foul out spark plugs and dilute the oil. Had it happen with a way over jetted Holley carb on a 340 Mopar once. I don't recall the headers getting hot enough to glow though. So your theory is that the extra unburned fuel mixture was combusting inside the already hot exhaust pipe causing it to heat up till it glowed. Going by what you described with your experience that must be the logical explanation. I know that a too lean condition with a 2 stroke can cause a melt down, but that's just because of not enough lubrication on the moving parts. Different animal than a 4 stroke.
 

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Well in my experience, as Dave said, late timing well cause that. Over revving will cause it too. If you take a plug out and it’s clean as a whistle or take a plug out and it’s sooted up, In my mind the clean one is in a mixture that’s lean to a point, or burning correctly and the sooty one is in a rich mixture. I have no data to proof that. So I’ll go another route to explain. Acetylene and oxygen torch’s.
Sharp blue flame tip will heat things much better than a blue flame with yellow tips. So, the yellow tips are caused by to much acetylene, rich mixture. Just my thoughts. Please correct me if wrong.

Noel
 

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Discussion Starter · #27 · (Edited)
I used to "read" the spark plugs in my street car motors after changing camshafts and or intake, carburetor, ignition upgrades, etc. If the plugs were showing a blackish sooty color I knew I needed to make some changes. That or not cruise, idle around so much and run the car harder. That was sometimes hard to do and stay within the expectations of the local law enforcement personnel. So it was a delicate balance trying to have a motor that would really "get it" when you wanted to play and having something you could cruise around town and not get loaded up and buck, snort and run crappy. Now a days a computer keeps everything tuned just so for all possible driving situations. Way back when, I was seemingly under the hood on a regular basis changing jets in the Holley or metering rods in the Carter carbs and adjusting the timing. I had to wire the coil to a toggle switch because when I had the timing advanced so the motor ran the best on AV gas it was hard to start when hot. I would get the motor cranking over and then flip the switch to energize the coil. I often would go to our local airport on Saturday morning and get a tank of AV gas then go home and crank the timing up so I could "play" that night when all the local car guys had thier toys out. Wow, going down memory lane here.
 

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Discussion Starter · #28 ·
I would agree about the flame at the tip of a torch. If the flame is a bit yellowish you have too much gas and or not enough oxygen. Now I'm wondering if there is a difference between an incorrect fuel oxygen mixture ( in Stews case, too rich ) inside an exhaust system and how a torch produces heat with the flame out in the open. Inside the exhaust pipe a rich fuel mixture produced too much heat, with a torch too rich a fuel mixture produces not as much heat. And of course we are talking about two different sources of fuel here too. The torch is using a compressed gas ( acetylene ) and the motor is using an atomized liquid ( gasoline ). If that means anything? Boy this is getting to be like science class! Interesting!
 

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Discussion Starter · #30 ·
Maybe comparing the flame of a torch and what goes on inside a motor is like comparing an apple to an orange? Just thinkin' Well anyway, I guess we have to agree that unless things aren't just about perfect that there will be issues with an internal combustion engine. I think most of us have been down that road at some point.
 

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Well, every comparison has some advantages and disadvantages. But at least the combustion needs to be as well adjusted as possible.
The difference between our tractor engines and a car engine is, that a car engine works much more with the gas pedal as an tractor engine. So providing the right amount of fuel depending on the gas pedal requires a more complicated carburator.
The big benefit of our tractor or even wood splitter application is, that the engine is running with a governor. It is supposed to run with a constant speed, which is adjustable but not as "nervous" as with a gas pedal. So finding the right setting can take a while but once its done it is good for a long time.
I prefer to run these kind of engines better "rich" than "lean", just to avoid the possible damages a lean combustion can do.
 

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Well Im no expert, but to me, any flame wether it’s a torch, gas engine, kerosene lamp, wood fire, oil furnace they all can burn rich or lean. Not to hard to figure out. To much fuel or to much air. Have the mixtures set right and they burn fine. I don’t think the apples and oranges have any bearing on it.

Noel
 

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Discussion Starter · #36 ·
No video today, sorry. Nobody here to run camera right now. I started off by going to the hardware and picking up some new grade 5 bolts. Just because it made me feel better, knowing this machine quite possibly will have a bit of a workout this coming year. Everything bolted together fine, no issues. I started off splitting a couple pieces of wood I had in the garage then moved the splitter out by the barn to look for more pieces I could split. I didn't find much that really needed re-split as everything was pretty much to size already. I had it running maybe 15 minutes total and the new motor ran great. I discovered that it was pretty happy working away at about 2/3 throttle. I used to run the B&S motor about 1/2 throttle, and it did just fine. I would throttle it up some when I got into the really dense, knotty, twisted stuff. Never needed to run it "up against the governor" to make it split. The old B&S was 8hp and the new Predator is 6.5hp.so I might need to wind this motor up a bit more when I get into the heavy stuff. We will see. So far, I am happy with the new motor. Worst case scenario I could put the old motor back in place or hunt up a better one the same hp. I think everything will be ok just like it is now though. I noticed that there wasn't much heat transfer from the muffler heat shield to the throttle cable so that should be good as is. I never did any kind of change on the motor mount plate as there would need to be some sort of trough between the channel mount and the plate underneath. Can't drill down through the bottom plate or notch it out because there is an angle iron stiffener welded in place right there. Not a big deal, I'll just use a scrap of cardboard or piece cut from a beverage can for a drain spout. And thats all I have right now.
Wood Font Circle Nail Number
Tire Vehicle Automotive tire Motor vehicle Automotive exhaust
Tire Wheel Automotive tire Hood Tread
Tire Wheel Automotive tire Tread Wood
Wheel Tire Land vehicle Vehicle Automotive tire
 

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Looking good for sure. Only thing I would suggest is those air cooled engines were designed to run full throttle in order to move enough air to keep them cool. Lot of ruined engines by people taking it easy on them. Your engine, run it the way you want to.
 
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