培训笔记本❘史蒂夫·舒珀特（Steve Shupert）
当您宣誓就firefighter，您还致力于成为专业的电动工具操作员。了解这些强大的发动机如何工作并维护它们将有助于确保您和您的社区安全。
Two-cycle engines are typically used on链锯，，，，旋转锯，还有一些舷外船引擎。两循环发动机也没有油曲轴箱。内部零件的润滑是通过特殊的油和汽油或直气的混合物施加的，将油注入圆柱体中。If your two-cycle engine uses gas oil mix, check your owner’s manual for the proper fuel-to-oil ratio, such as 40:1, 50:1, and so on (e.g., 50 parts of gasoline to one part of oil). Two-cycle oil containers are sized to give you a correct ratio based on the size of the gas can you are using. Because they have no oil crankcase or sump, they can be operated in almost any position. Too much oil will cause the motor to smoke excessively and foul the spark plug quicker. Not enough oil will cause the internal engine parts to be damaged. Most saw manufacturers recommend89-辛烷，没有乙醇。橡胶零件（例如燃油管线）可能不具有乙醇耐酒精性，它们会失去形状并变得柔软。
（1）燃油引物灯泡和阻塞杆处于完全扼流圈位置。（作者的照片。）
如果您将自己的两循环燃料混合，请使用优质的两循环油作为电动机。搅动混合燃料罐，以确保机油/燃料的正确分配，尤其是在坐了一段时间的情况下。如果使用合成混合油，请按照容器上的指示进行操作。在合成和传统的两循环混合油之间，油与气体的比率可能完全不同。一种昂贵，值得信赖和万无一失的替代品来混合自己的燃料，是使用可供购买的众多燃气/机油预制之一。这些没有乙醇，将具有正确的油混合比，长长的保质期和正确的辛烷值。购买与您的工具相同的比例。由于这些电动机的运行速度比四循环发动机更热，更快，因此它们需要更换火花塞，并且对旧的陈旧气体更敏感。
引擎扼流圈
Before you start a gas engine, understand how the choke operates. Photos 2 and 3 detail the choke plate for a small engine, which could be a two- or four-cycle; it is the same. The choke (on the left) is in the off—or “open”—position for a hot/running engine, allowing a full flow of air in to mix with fuel and sending it to the engine cylinder to be burned (exploded). The image on the right shows the choke in the on or “closed” position. Placing the choke in the starting position (cold engine) limits the air that flows into the fuel/air mixture and creates a fuel-rich condition for easier starting, just like when using starting fluid. Engage a middle position for cold starting after the engine “chugs.” However, this will not keep running.
（2）在“打开”或关闭位置中的扼流圈。
（3）在“封闭”或位置上的choke。
If you are using a hand choke cable, closing the choke usually requires pulling the choke handle out and attempting to start the engine; the engine will then likely chug but not start. Push the choke in halfway, and the engine should start. Finish by pushing the choke in to the fully open position, and the engine should smoothly idle up. If equipped with a fuel primer bulb, pump the bulb about five or six times until it is full of fuel.
启动引擎所需的四件事
All small gas engines (two- and four-cycle) need at least four things to start and run, which follow:
- 气缸压缩。当您拉动启动器线时，您会感觉到紧密发动机中活塞骑自行车的“流行歌曲”。
- Fuelwill be delivered to the carburetor, functioning fuel line, and fuel filter.
- 火花旅行到一个正常的火花塞。
- 空气通过过滤器进入化油器。
如果这四件事缺失或无法调整，则可能会遇到两次或四循环电动机的问题。
启动冷两循环发动机
When attempting to start a cold two-cycle engine, do the following:
- 将扼流圈（将空气控制在化油器中的蝴蝶阀）充满。
- 全速设置油门锁。
- 如果配备，请按减压阀。
- 轻快地拉动启动线。
- 当锯“弹出”和“ chugs”或试图启动时，将choke移至OFF或“运行”位置。
- Repress the decompression valve.
- 拉动启动线直到锯开始。
您必须开始对电动机（在高噪声环境中的“ chug”）产生感觉。您应该足够了解声音，可以在黑暗中做到这一点。如果锯仍在关闭后仍然是“温暖”（跑步/工作），但是您需要重新开始，也许在五到10分钟之内，而且外面也不冷，那么您可能不需要充分的cho。
启动洪水的两循环发动机
It’s easy to flood a two-cycle engine (“flood” meaning there is too much fuel in the carburetor after repeated failed attempts to start). Indications of a flooded engine include a strong smell of fuel or the engine will seemingly fire but not start with no other indication of a maintenance issue. The fuel-air mixture in the cylinder is too rich to ignite and start the engine. Therefore, you must remove the excess fuel and do the following:
- Push in the choke control to deactivate the choke and press the throttle control all the way to “full throttle” while pulling sharply on the starting cord many times. We keep the choke off because the engine is flooded, so to get back into the proper fuel-air ratio, open the choke to allow in more air. This may take a second person to help. Ideally, the engine will chug or try to start; when that happens, go to full choke.
如果这不起作用，请执行以下操作：
- 取出火花塞，确保火花塞孔从您身上转开，因为燃料会喷出。
- 拉动启动绳以清除燃油的气缸。
- 干燥火花塞并重新装修。
- 遵循机器的正常起始过程。
如果您正在紧急工作，并且有人淹没了锯，那么最好只有另一个锯。
操作准备
当执行设备检查,只运行了long enough (one to two minutes) to check that it is working. Allowing the saw to sit idle only allows unburned fuel to collect in the cylinder, speeding up the fouling process inherent with two-cycle motors. The motors are tuned to run at working loads/speeds—not to sit at idle—similar to a generator。A chain saw needs to be used to stay in good operating condition。
（4）Some newer engines have a cylinder decompression valve. This valve looks like a button. By pushing it in, you allow some of the air in the cylinder to escape during the startup. When the engine starts up, the valve resets itself. This makes it easier to pull the starter cord.
（5）Washable air filters. The paper style gets thrown away. Gently clean and rinse with dish detergent and reinstall when dry.
（6）排气火花引导屏幕。
（7）许多发动机在化油器调节螺钉上装有“ EPA限制器”盖；他们已经准备好防止任何人的调整。要调整它们，您将必须获得正确和相应的螺钉；有超过六种不同的样式。
如今，许多两循环电动机都有自加密的化油器，随着空气滤清器装有碎屑的负载，化油器会重新启动化油器。确认引擎正常运行后，将其关闭并进行热的restartwithout engaging the choke. This helps simulate fireground conditions and ensures the hot engine has no issues.
Breaking in a New Two-Cycle Engine
检查SAW的物理状况并确保已准备好操作。加油在内，包括钢筋油（用于链锯）。启动锯，让它在空闲时运行。几分钟后，简要地run it up to ¾ speed for no more than two seconds.
Allow it to run until it is out of gas; failure to do this can shorten the life of your saw. Following this procedure allows for proper wearing in/lubrication of the cylinder and rings.
Maintaining Two-Cycle Engines
不良汽油。如果您的发动机闲置时，加速过程中经常摊位，或者根本无法启动，那么您的汽油很可能会变质。您还可以判断汽油的外观是否不好。如果它比平常更黑或有酸味，那可能很糟糕。用锯切割的另一个好理由是它有助于保留新鲜的气体。橡胶燃料管线的软化引起的燃料泄漏或性能差，乙醇添加剂发生。乙醇通常不知道乙醇。因此，请与汽油站有关乙醇含量。
If you are having trouble with the motor gasoline, one of the first things to check or change is the fuel. Simply dump it out and properly dispose of it. Gasoline straight out of the pump is typically good for three to five months. If treated with a fuel stabilizer (typically one ounce in 10 gallons of gasoline), you can expect six to eight months of good performance. Canned premixed two-cycle fuel has an estimated two-year shelf life after opening.
汽油变坏了，因为它的许多挥发性化合物随着时间的流逝而蒸发，辛烷值减少了。稳定剂可用于两循环混合物，直汽油，海洋燃料，柴油和E85。稳定剂限制了这种蒸发，但如果您的气中有水，这是另一个常见的问题。大多数汽油还添加了乙醇。乙醇吸引并握住水和稀释燃料，腐蚀发动机的金属零件。它也可以冻结。干气或其他类似产品与水分子结合，从而减少了这些负面影响。如果您还要长期存放发动机，请运行发动机，直到用处理的燃料干燥，然后将任何剩余的汽油排入批准的容器中，然后正确处理。
火花塞。火花塞是点火系统中的最终元素，该点火系统会产生点火源（Spark），该点火源发射气泡混合物。此操作键从发动机飞轮和拾音器线圈上进行的时机，在适当的循环中向插头发射电荷。插头可更换。小心，以免交叉线程火花塞，用手开始，然后使用扳手完成拧紧。还要注意不要破坏瓷器或从耐受性中敲出差距。
The gap is typically set right out of the box, but it pays to make sure. A “feeler gauge,” which is a measuring device with finely calibrated wires or thin metal strips with the width indicated on each filament, is used to correctly gap the plug to the size indicated in the tool’s manual. Bend the side electrode slightly so the feeler gauge just barely fits. Look up the spark plug specifications in the tool’s owner’s manual; do not waste time cleaning the plug—just replace it. When gapping the plug, check the manual for proper gap dimensions.
空气过滤器。确保空气滤清器干净。更换空气滤清器时，关闭蝴蝶阀/choke，以防止滤清器在更换过滤器期间掉入化油器中。有很多木屑和木屑飞来飞去，链锯上的过滤器很快就会变得非常脏。
火花screen.消音器内部的火花逮捕屏幕可以用碳矿床堵塞，尤其是在带有脏空过滤器的较小锯子上。堵塞的过滤器导致锯过滤量太丰富，没有燃烧的燃料会导致沉积物。过度闲置的锯会导致碳堆积。定期给它做一个良好的艰苦运行 - 不仅仅是闲置。如果屏幕犯规，则很容易用脱脂剂/溶剂清除和清洁。
Don’t Screw with the Screws!
Do not change the settings on your carburetor unless you know exactly what you’re doing and have the proper tools. The carburetor setting is seldom the problem; check to make sure everything else is working properly. Check for proper air and fuel flow through the system. If you compensate for poor maintenance (a sign of a dirty air filter) by changing the factory settings, then you may be chasing your tail trying to keep the engine running. If your saw has a clogged air filter and you change the carburetor settings to compensate, you will have to do it all over again when you put a clean new filter on the saw.
Keeping your two-cycle engines running at peak efficiency is vital to safe and fast fire/rescue operations. At idle, neither the chain nor the rotary blade should be moving. You will need a single cylinder tachometer and to know the high-/low-idle factory settings to adjust the carburetor.
史蒂夫·舒珀特（Steve Shupert）是一名37年的公共服务退伍军人。他从俄亥俄州蒙哥马利县的迈阿密谷消防区退休，并担任俄亥俄州特遣部队＃1联邦城市搜救的救援队经理。Shupert还是FEMA救援子组的主席，也是501C3的培训主任Crash Course Village在俄亥俄州的Kettering。
