Just to see what would happen, I filled my motorized bike with 1 quart heating oil and 1/4 quart mixed gas. So obviously it started smoking really bad, but I was able to get to 42mph vs the 35 or so I would normally get. (bike has shift kit and dirtbike expansion chamber). Any ideas why this would happen? Heating oil is about 1/4 as thick as 2 stroke oil.
Odd... ran heating oil as gas, 7mph increase in speed???
- Thread starter rudyauction509
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Also before the heating oil all plug chops (did 5 at different speeds) were light to dark brown, none were white and none were black. And I never had 4-stroking problems except the first couple minutes on a cold day.
And another thing that happened, the engine now overpowers the clutch and it starts slipping. The clutch is clean, and I'm going to try to tighten the main spring to reduce this slipping.
Can you afford to lose this engine?
I have no idea what will happen, but that is certainly a possibility.
If you continue, I'd suggest changing your mix to 50/50 before making mechanical adjustments. Just to get a good understanding of what it is exactly you are getting out of it. Let us know (video?) what kind of smoking you're seeing at start up and under load, smell, sounds etc.
Interesting. Thanks for sharing.
I have no idea what will happen, but that is certainly a possibility.
If you continue, I'd suggest changing your mix to 50/50 before making mechanical adjustments. Just to get a good understanding of what it is exactly you are getting out of it. Let us know (video?) what kind of smoking you're seeing at start up and under load, smell, sounds etc.
Interesting. Thanks for sharing.
"Can you afford to lose this engine?" --Trey
It's a good question. But I suppose rudyauction has already considered that.
We MB types can sometimes be a bit wild, huh?
Anyway, fuel oil is just about the same thing as diesel fuel isn't it? I'm thinking that the compression in a happy time engine can't possibly be enough to make that fuel/air mix burn on it's own. The way a diesel engine does. So I suppose it's waiting for the spark and burning then.
For it to burn with something like the same power, ounce for ounce, as mixed gasoline doesn't surprise me, I guess. From the sound of it, you're getting even more power than you expected, huh?
But even that doesn't surprise me a lot. Still, this is just the musings of someone who doesn't really know anything about it. So it's probably not going to get us anywhere.
But it's an interesting experiment. I'd be concerned about proper engine lubrication.
Other than that, best of luck to you.
It's a good question. But I suppose rudyauction has already considered that.
We MB types can sometimes be a bit wild, huh?
Anyway, fuel oil is just about the same thing as diesel fuel isn't it? I'm thinking that the compression in a happy time engine can't possibly be enough to make that fuel/air mix burn on it's own. The way a diesel engine does. So I suppose it's waiting for the spark and burning then.
For it to burn with something like the same power, ounce for ounce, as mixed gasoline doesn't surprise me, I guess. From the sound of it, you're getting even more power than you expected, huh?
But even that doesn't surprise me a lot. Still, this is just the musings of someone who doesn't really know anything about it. So it's probably not going to get us anywhere.
But it's an interesting experiment. I'd be concerned about proper engine lubrication.
Other than that, best of luck to you.
I'd say heating oil is like mixing diesel and 2-stroke oil at about 50-50 ratio. It's thick like oil but much less than say 10w-30 motor oil. When you get it on your hands if feels like oil, so I'm not really worried about lubrication.
By the way I thought it wouldn't run at all because the oil's so thick compared to gas. I pulled the cylinder head and the cylinder has a nice layer of oil on it, so it's definitely getting lubricated. I won't be using heating oil as gas much though because of possible carbon buildup. I do have about 30 gallons that I will probably use in emergencies when I have no gas around.
Not sure, just guessing here but I have to wonder if the heavier viscosity of the oil raised your compression a bit and helped piston ring seal which might have resulted in the performance increase you noted. Like I said, just a guess.
Even if this is a fact I wouldn't suggest long term use of that fuel mix. I think you'll find that fouled plugs and/or exhaust systems could result.
Interesting experiment nevertheless.
Tom
Even if this is a fact I wouldn't suggest long term use of that fuel mix. I think you'll find that fouled plugs and/or exhaust systems could result.
Interesting experiment nevertheless.
Tom
It makes sense to me because the amount of energy in the heating oil compared to gasoline similar to deisel fuel and why deisels typically get better mailge than a comparable gasoline engine... until you start having fun with the power and that good milage quickly disapears... Do you have a way to monitor your cylinder head temp? It would be a good idea to make sure you're not running it too hot, otherwise it sounds pretty good.
I remember someone telling me about mixing deisel fuel with gasoline to make more power (which I thought was totally insane at the time) but the guy went on to say the extra boost in power was short lived since it would usually burn up the engine in short order. After understanding why this works it sounded like a good idea to get more power out of an engine except for the part about the extra heat you gotta find a way to deal with. Being a 2 stroke and in the middle of winter you can get away with a little more than a 4 stroke or in a hotter climate etc.
I remember someone telling me about mixing deisel fuel with gasoline to make more power (which I thought was totally insane at the time) but the guy went on to say the extra boost in power was short lived since it would usually burn up the engine in short order. After understanding why this works it sounded like a good idea to get more power out of an engine except for the part about the extra heat you gotta find a way to deal with. Being a 2 stroke and in the middle of winter you can get away with a little more than a 4 stroke or in a hotter climate etc.
The extra compression theory is also a valid one since these engines have such wide end gaps to start with. Like I mentioned in my post, I'm sure the extra power is nice, but fuel does convert heat into power and the more energy in the fuel, the more heat that's generated.... That's my only concearn here, but if it runs cool enough and doesn't foul your plug or your engine with soot you might be able to get away with it for short runs.
I'm going to pick up a digital oven thermometer for about $5 and extend the thermistor to the cylinder head. I've done this on dirtbikes and mopeds after adding performance parts to make sure I wasn't overheating them, should also work here.
That'll work or you can get a cut gauge where the thermocouple goes under the sparkplug, these are really accurate and fairly cheap, but your idea should work since you've done it on other bikes and know what the temp should read.... you should write a post how to make a temp gauge out of an oven temp thermometer since that's probably still less expensive than a cheap cht gauge and spark plug mounted thermocouple. Does that read the same or does it read less than a regular hauberk since the thermistor would be mounted differently? I use an infrared laser temp meter which works great but gotta take the reading with the bike parked like immediately after a hard run to get the most accurate reading.
I used a friends $100 ir thermometer to compare the oven thermometers readings, the oven gauge was within 15 or so degrees F every time, which is close enough to be useful. I usually clamped the thermistor in a washer on one of the cylinder bolts, but one time I embedded it in an unused bolt hole near the cylinder bolts, that was originally for an autochoke device that used the cylinder temp to control choke.
i'll make a thread about it when I do it again, should be somewhat soon.
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A side effect of the heating oil is the engine is really hard to start and warm up after being in the cold for several hours. Think 5 minutes of revving with the choke partly on to keep it from dieing, but once warmed up it runs great, other than touchy idle. I'm going to do a bit more testing tomorrow then dump most of the tank and put regular mixed gas back in.
What would go wrong with the exhaust? I understand the spark plug, I have extras and a wire brush will remove the carbon buildup. I have a 125cc dirtbike exhaust on it so it'll take a lot of carbon to plug it up.
What would go wrong with the exhaust? I understand the spark plug, I have extras and a wire brush will remove the carbon buildup. I have a 125cc dirtbike exhaust on it so it'll take a lot of carbon to plug it up.
B&S had 4stroke engines for foreign markets where gas was expensive but the lighter fuel oils were not. It had a slightly thicker head gasket re-jetted carburation and a two compartment fuel tank. You started it on gas until it warmed up the switched the valve to the fuel oil tank. When shutting down you did the reverse until the engine purged the oil and was running on gas, then shut it down.
There is a good bit of lubricity in the lighter fuel oils. If you are more into experimenting than worrying about the engine, you could probably reduce the mix a bit to improve running/starting.
There is a good bit of lubricity in the lighter fuel oils. If you are more into experimenting than worrying about the engine, you could probably reduce the mix a bit to improve running/starting.
Hey RC! Hows it going?
Never saw one of these but they were on the microfiche way back when. I believe they were current around the middle of the last century. This was also a method used during WW2 to run the cars on kerosene or coal oil what ever that was as gas was rationed but not the lesser distillates.
Never saw one of these but they were on the microfiche way back when. I believe they were current around the middle of the last century. This was also a method used during WW2 to run the cars on kerosene or coal oil what ever that was as gas was rationed but not the lesser distillates.
Yup.. I remember engiens back in that era with compression ratios as low as 4:1 just so they could burn these cheaper fuels without burning up the engines.. Power was almost non existant as a result.
