4-stroke engine valve clearance adjustment and bearing replacement

Valve clearance adjustment: gasoline engine work after a period of time or cleaning is not just a pile of parts assembled back can guarantee that it will smooth functioning. YS, OS, Thunder Tiger four-stroke engine factory as this topic to share please correct me if any linguistic errors.
   
A: Open the valve cover, remove the spark plug, the rotation spindle top dead center (piston walked usual propeller bushing there is a mark will be exactly aligned with the gasoline engine chassis directly above the cylinder most vertex Next to that point), this time shaking valve rocker will have a certain gap (if the intake and exhaust are very tight like him to turn the spindle lap); this point you adjust valve clearance.
   

B: Open the engine side two screws Timing gear cover, you can see the the spindle above fit a gear gear called "Timing gear with a clean cloth to wipe gear front you can see there is an approximately 0.8MM dots, please pay attention to the subject of this dot that according teeth is just above front spindle or timing gear cover (depending on the original manual prevail).
   

C: come up with the valve to adjust the gap-chip 0.04 and 0.1, two, I'm used to the intake tune 0.04MM; exhaust (near side) exhaust pipe tune 0.1MM; clearance tablets advancing to the contact point of the valve top and rocker not be pushed into the gap is too small; (the piston pushed to the outbreak of the system on the dead point, this point is not entered into the system / exhaust top dead center) relax fixing nut counterclockwise rotation of the adjustment screw until the gap piece can be pushed go re-adjustment screw clockwise to the gap piece again during sliding left hand leaning on the adjustment screw, the right-hand turn to tighten the fixing nut either. With 0.1MM gap chip to adjust the exhaust gap. (This adjustment is into fast row slow, the advantage of a strong power output. Drawback is idling unstable, and prone to overheating. Depending on personal preference I are adjusted to row fast into slow, the advantage is idling stable and difficult to overheating, fuel-efficient. drawback is that average power output of 140 aircraft is sufficient.) Timing gear cover back cover locking view steam door packing paper are not damaged (especially YS rc model gas engines Please do not can leak) or else you'll have an "the next elimination" (no force) how to tune the troubled rc aircraft model gasoline engine; packing paper is broken, do not tense, a put do not need to find a thick brown paper bags according to the shape of the shear to spend money to buy.
   

Replace the engine bearing the timing: the ordinary engine work should not exceed 9500 rpm speed 1500-10000 rpm high speed best flight after a period of time, bearing gap, if you use a balanced propeller launched engine Special Ma (experience) (or turned by hand crank, not smooth or foreign body sensation). This is the opportunity to change the bearing because of the large gap to a degree of wear (leak) produces piston side (the engine will have a very big shock, after the crankshaft will be bending phenomenon can not see with the naked eye.) forces could not get ready to get a new engine. When you have the engine apart to clean, it is recommended that bearings with replace.
   
Steps:
    A: (two-stroke rc gasoline engines) Remove the cylinder head, rc gasoline engine cover, cylinder liner, piston, propeller pad (this part is commonly known as the force monkey bearing exit) pulled out from the front of the the fixed latch, spindle front bearing ( I remember after looking for a hard wooden stick from behind, gently tapping the front bearing spindle), the entire aircraft model gasoline engine with efficient hair dryer or gas torch (the kind used by the plumber) heating the rc aircraft gasoline engine DLE30 to a certain extent, the hand I remember wearing cotton gloves to avoid burns, the engine cover down in the rear bearing can withdraw a knock on wood. Bearing note of ID such as 6903,1600 X, R6X .... If you can not see the ID when the amount of outer diameter and thickness to the bearing shop to buy back change.

(Four-stroke gasoline engine) Remove the the steam valve cover, rocker (bird), cylinder head, plunger, top tube, Timing gear cover, cylinder liner, piston shaft, piston rod (dog bones), propeller lining pad (which parts need to be commonly known as force bearing exit monkey) pull out from the front of the, fixed latch, spindle (remember the spindle to knock before propeller fixed bolts in the front spindle and then plastic hammer to knock out this method can avoid the spindle thread knocking bad); remaining steps with the two-stroke.
   

B: buy bearings engine by demolition anti-step parts - Replace.
    C: (especially any screws lock rc model gasoline engine cylinder head) locking method of diagonal three sections: first all the screws all the bolt on the locking screws turn tight semi-circle in 12:00, 6:00, 2:00 , 8:00, 4:00, 10:00; then in accordance with the the above angular position locking screws (unless gasket this method lock cylinder head to ensure airtight).

The essential information about the model airplane

What is the model airplane
Size limit specified in the contest rules formulated by the international routes linking "model airplane is a heavier than air, with or without the rc gasoline engine can not be manned aircraft, called model airplane.
The technical requirements:
Maximum flight weight with fuel, including five kilograms;
Maximum lift area of one hundred fifty square decimeter;
The largest wing loading of 100 g / square decimeter;
Piston engine working volume of 10 ml.

1, what is aircraft model
Generally believed incapable of flight, the model produced by a certain percentage of the actual size of some aircraft called the aircraft model.
 

2, What is the model aircraft
Generally referred to as a model aircraft in flight model, called the model airplane.

Two, the composition of the model aircraft
Model airplanes are generally manned aircraft, mainly composed of five parts of the wings, tail, fuselage, landing gear and rc gasoline engine DLE 111.
 

1,wing --- generate lift device model aircraft in flight, and to maintain lateral stability and model aircraft flying.
 

2, tail --- including the two parts of the horizontal tail and vertical tail. Horizontal stabilizer can be maintained the pitching stability and model aircraft flying, vertical tail to maintain direction and stability of model aircraft flying. Control model aircraft lift the elevator on the horizontal tail, and vertical tail rudder control model aircraft flight direction.
 

3, fuselage --- model links into a whole trunk part called body. Necessary control parts, equipment and fuel can be mounted inside the fuselage.
 

4, landing gear --- for model aircraft takeoff, landing and parking device. Front landing gear, called the first three-point behind both sides of the three landing gear; the front of both sides of the three landing gear, followed by a called taildragger landing gear.
5, the engine - it is a model aircraft flight powered device. Commonly used in the power plant of the model aircraft: elastane beam, piston-type engines, rc jet  engines, electric motors.

Adjustment of the model fuel engine oil needle

First of all, a lot of my friends would ask: Your gasoline engine oil needle to open a number of laps? - In fact, this is an error, model car gasoline engine oil needle is not a \ "standard \" position, the fuel brand, then the temperature / humidity, oil needle set are not necessarily the same.

If I have an experience of value, Well, the main oil needle clockwise Off is coming to an end, and counterclockwise to open 3.5 to 4 laps, vice Clockwise Off to the head after 2.5 to 3 turns counterclockwise to open. This experience may not be applicable to you, but if you really did not grasp, is located in such a way look at it .......

Meet with needle:

The oil needle summarized sentence: low speed needle (the deputy oil needle) responsible for car accelerating from rest to the reaction speed, the more screwed in the faster; responsible for the high speed needle (main oil needle) the maximum speed of the car, the more screwed in The speed of the faster; idle screw is responsible for the car idling, the more screwed in idling the higher.

Main humidity needle affects throttle linearity, but also with the low speed needle related, novices do not move it.

Oil needle adjustment method is as follows:

1, the temperature is ready and coarse:

Ensure that the oil needle at the factory state, if you have been mixed up, put the main Clockwise Off to the head, open to 4.5 turns counterclockwise, Deputy Clockwise Off is coming to an end, to open 3.5 turns counterclockwise :)

Start car, so the car from the air, this time a little throttle, the engine running enough temperature (about 15-25 seconds)

Until the engine temperature reaches the work needs to start tuning.

2, the main oil-pin coarse:

Fierce reminder a few throttle (valve fully open), listening to the sound, full throttle, the gasoline engine sound is very sharp, dry, seems to have strength, but do not increase the feeling, you amplify the main oil-pin (inverse clockwise - the oil-rich)

Oil needle circle regarded as 60 minutes, each tuned amplitude for 5 minutes, and tune to the time until the accelerator is fully opened, the engine at top speed, the sound is strong and quite sharp.

3, the main oil-pin fine-tuning - listening Resolution bit:

Good set of gasoline engine sound is completely commanded listen to your fingers, not your fingers move, and also stick to their voice

Then full throttle, and then immediately return to the idle position, listening to the sound of the engine.

Sound should be so: the tone is very high speed when, immediately return to the idle time is very calm and coherent, absolutely no \ "tone classification \"

High-speed return to idle when the normal tone: wowowowowo ..... dadadada

High-speed return to idle when the incorrect tone: wowowowowo ..... ooooo ........ dadadada

The orange above idle stage \ "o \", \ "tone \" in high-speed landing \ "idle \" process, there is a do not listen to the finger command of tone, this tone is the symbol of the "chasing oil.

"Chasing oil," said the engine by the high-speed to the idle process, the oil supply is inadequate - so we hear the engine tone is inconsistent, the middle seems to have refused to slow down the pitch, even the engine sustained high-speed to get down .......

Encountered "to chase oil" we must enlarge the main oil needle some (counter-clockwise - the oil-rich) until it meets the normal tone, no do not listen to the finger command of middle tones.

Purposes of the tuning of the main oil-pin is the engine oil needle closing (clockwise) to close to "recover oil," the point (that is the limit of the engine), try squeezing engine a power and speed

4, set idle

First, take the air filter, remote throttle control to push the brake, the valve clearance should be 1 mm, if not, adjust the idle speed screw.

Next, do not touch the remote control throttle, steering gear return to idling state, observe the valve clearance should still be about 1 mm. If not, adjust the position of the midpoint of the steering gear of the remote control.

Immediately returned to idle to full throttle, if the engine immediately turn off, to increase the idle speed (idle screw clockwise to increase the idle speed).

The idle valve clearance generally not greater than one millimeter too much. If your valve clearance has been much greater than 1 mm, the rc gas engine is still very unstable easily fire death, attempting then to check, to see if the fuel quality problem. If the idle speed is too high (the wheels began to turn, or the idle high pitch), you properly reduced idling or sustained over time, the clutch is likely to burn.

5, the vice needle adjustments:

Vice needle called the low speed needle, by definition, which is in charge of the engine of the state in the low-speed state. Want to play the rise of the friends need to be aware of the low speed needle adjustment :)

Full throttle, then back to idle, listening to idle when the pitch is too low (if there is phlegm in the throat), but when you suddenly accelerate when the throttle response \ "slow \", the Vice the oil needle decreases (clockwise) until tuned to rapid throttle response, acceleration linear no \ "delay \" feeling. Deputy needle closing small will make to start faster, but too small, the same will be chasing the oil situation, once tuned small needle, chasing oil, you can zoom Deputy needle (counterclockwise ).

Relatively simple but practical the vice oil needle adjust the way: the vice oil needle shut open to about 3.5 turns, then the car, briefly fierce refueling see cars start fast offensive, objectionable words on 5 minutes 5 minutes to closing a small vice oil needle, until the most powerful vehicle to accelerate from rest (do not be blind pursuit of violence lead to "chasing oil).

6, the running state of the overall fine-tuning:

Stationary state regulation after, you also need careful adjustment hierarch oil needle on the track.

First tank full of fuel, and high-speed walking laps of the track to see whether enough speed.

A maximum speed of closing small main oil needle (clockwise - Each tune "3 minutes" amplitude), you can test every 1-2 laps and then walk again tuned again - until the engine play a desired speed, and there is no overheat.

Check the temperature of the gasoline engine, the more professional approach is to use the model-specific infrared thermometer:

Of course, there are simple and cheap check the rc engine temperature: drop a little water on top of the engine cooling - water points within 3-5 seconds evaporation is a normal phenomenon, such as water points immediately evaporate, this is overheating, now the main oil pin. the Big 5 minutes turn (counterclockwise) and then walk a few laps, again check engine temperature is back to normal ... it will be very dangerous Oh ...

Of course, using the method of water droplets generally only suitable for experienced veteran, I have not seen the first touch engine novice proper use of water droplets law, so if you are new novice, or buy a thermometer it :)

Proper engine tune, the engine should be generated at a high speed when a strong high-frequency sounds, and the obvious thin smoke should be discharged from the exhaust nozzle.

Several easy to normal novice worries:

1, the rc engine turn up the intermittent sound of some metal collision: Ignore it generally is the voice of the clutch and gear when inaudible

2, the rc engine is a fuel on the fire death: General Deputy needle too rich oil received little vice needle like

3 idle for a few minutes, touched on the fire death: normal, because idling case poor discharge of oil, slow throttle, high-speed operation ejected plot engine oil can

4, the resumption of oil when the engine speed is not down, as if in singing Diaosang Zi: see lean?

A brake on the dead fire: Make sure the brake case, whether the damper remain about 1MM gap. If the damper shut the course will turn off, if the damper is too large, the clutch has combined brake equal to forcibly stopped the engine, of course, will turn off.

6, Rc engine heat succeeded not touch: the engine is originally should heat succeeded are not touched.

Simply start vain:

Ignition electricity? - Fire head screwed down connected to the igniter, attempting son should be very bright, if not bright enough, charging it!

Oil into the carburetor it? - Look at the oil is not oil tank arrived carburetor you? If not, start blocking the exhaust pipe to start it and see.

Determine the oil is not too much flooded wet attempting it? - Attempting to remove, empty pull a few rc engine (electric start on idling a few), and can emit excess fuel, to avoid fuel excessive flooded wet attempting.

The electric starter electricity enough? The NRK method correct? - Start fast enough, or pull the right way, can also cause distress, take a look at our pull video, learn about the way .....

8, the engine is very tight, turn no:

Is generally the area of ​​the oil in the engine too much removed attempting empty pull several integrated oil discharge can, do not be hard! ! Otherwise it will damage Recoil / electric start, and even gasoline engine damage (such as damage to the back cover, damaging the rear cover teeth, damage to the one-way bearing, even the most serious we have seen hard to the connecting rod and crankshaft broke !)

If discharged integrated oil tight (usually the new engine will be the case), you can fire head screwed loose a little, let the engine a little leak, so that you will not be so tight, so do not start the gasoline engine will cause damage to other parts: )

Last piece of advice:

1, the novice is best to let a veteran to teach in the next (of course it can not find people to teach not pull, huh, huh)

Too oil-rich or too lean the engine is not good, do not think the oil-rich is to protect the engine, monitoring gasoline engine temperature, and not too violent destruction of its most important :)

3, for many novice mistakes are very concerned about, and sometimes I am afraid are distressed sleep well, in fact, not necessary.

Gasoline engine is not so delicate, and model car is a toy, do not take it too seriously - tuning that short period of time, long as not too violent to destroy the engine does not have too much harm, rest assured, waiting for you play car for a long time, we understand that many fear is completely not necessary.but we can buy the cheap gasoline engine from the online shop, cost is not so much as before, so i think it is very important to get funs from the fly of the aircraft.

Necessary knowledge of the aifcraft model

 Aircraft model is welcomed by more and more people.It has been a very expensive hobby and many people can not afford it.But now it has changed.Online shop make more and more expensive things become cheaper,we can save much cost and get it with a low price. So online shop has also changed many things, especially our shopping style.The cost has been decreased and there is no doubt that it has became many people's entertainment style and many people regard it as a very important leisure way after works.and i am also a aircraft model lover and i have played it for many years. now i want to talk about some necessary information about the aircraft model.

1, No need the good looking aircraft, most important is the shatterproof and easy repair, do not choose beautiful and fast aircraft at first flight.
2. pay attention to safety, observed around the crowd to pay attention to the takeoff and landing, taking off and landing did not go well, rather smash the aircraft, but not go into people.
3. To initiatively learn more from the experienced people, but not keep playing alone, watching others play happily, but keep failed self. Don’t know the reason for the failure and do not know the reason even success.
4. the weather is poor (too dark) or bad weather (drizzle easy mechanical failure and loss of control), too much wind, never rush takeoff;
5. before take-off, be sure to move a bit remote control to confirm that all the action is normal.

6. the best way is to find a good experienced people, to ensure more effective psychological pressure also significantly reduce the absolute;
7. Maiden voyage need to stay away from people, vehicles gathered at. A novice test flight home built in the gathering of people and vehicles at less than 10 meters, the results of the aircraft to lose control and hit a million cars left uncomfortable dent.
8. more practice, whether it is up to nearly ten thousand flight simulation software G2 or free FMS, treat it as electric toys, play every day, practice every day, must be proven infinitely useful.
9. More question, just ask others when you doubt, I believe that as long as you asked politely, they are happy to answer.
10, More seeing, many website on the internet, which has many valuable information, and make use of it.by the way, i did not talk about the aircraft engine. It does not mean you need not pay attention on it. on the contrary, it is a very important factor in theses things. good rc engine will have a good fly. so do not forget it.

The aircraft sometimes higher, sometimes diving, sometimes gentle, sometimes somersault, full of tricks. Suddenly, the crowd burst into screaming, the aircraft draw a large arc in the sky,  and slamming headlong into the lake. But do not worry, this is not a plane crash, but a group of model aircraft enthusiasts made a small mistake. "Plane crashed!" Operating mistakes, Mr. Lin said with smile, "a high degree of tension, which is a nervous leisure."

Essential use of the Model aircraf gasoline engines

1, Run-in operation - all new engines must lower speed to a stage of operation, the time from half an hour to one hour or more, known as the run-in operation (grinding car). Very important operation, run-run-in operation is not good, the engine is not only the short life and small horsepower, it is difficult to start, but also bring a lot of failure. The said mill car useless, vain losses are one-sided understanding of gasoline engines and other. The correct operation of the run-in will never shorten the life of the engine, on the contrary will extend the life and improve performance. That new cars and motorcycles, for example, limit the speed of the plug is equipped with carburetor factory, or requiring speed should not exceed a certain limit, after traveling hundreds of kilometers before gradually increase the speed to run-various parts.

Steps as below:

The oil line parking off quickly after just grinding the car, the engine running for 1 to 2 minutes, until the engine cool slightly and then drove, do not continuous operate for a long time. Doing so, is also conducive familiar with this engine to start and adjust. Then, first at low speed for 20 to 30 minutes, if the cylinder head is not too hot (fingers on 1 to 2 seconds can tolerate), uniform speed can be slightly pressed regulator lever off smaller needle, improve a little speed. Continue mill car about 20 minutes. Replaced with a smaller propeller, and gradually increase the speed. Finally, turn to the propeller of the flying model, high-speed mill car 10 to 20 minutes.

The black oil may spray from the exhaust when the new gasoline engine just grinding. Finger extensor near the exhaust port, and will be sprayed with a layer of oil from the reservoir in the sun to see the glittering metal powder. Generally, to grind the car for half an hour, the black oil would greatly reduce or eliminate. Should gradually improve the speed, as the speed has been stable and the phenomenon of "heat death", grinding the car comes to a close, the engine installed in the model aircraft. Each engine requires grinding car insufficiency and the same time, to be determined according to the specific circumstances. Usually it’s about one hour.

After correct mill car on the small gasoline engine, it would have a good airtightness, easily started, easily and flexibly rotated, even if the continuous high-speed operation, the rotational speed is not changed (can be judged from the sound).

2. Installation - compression-ignition engine can be used as a power plant in the aviation, marine and land-based model. When used on a model airplane, it can be mounted in the nose front (pulled into formula), which is generally the most common patterns; also be mounted on the tail and other parts (push), then must be made after the paddle pad and the distance between the receiver front end face is less than the distance between the crank pin and the casing rear cover, so that after the passage of the propeller thrust paddle pad passed to the receiver end surface friction, not to the crank pin and the rear cover.

Small RC engine can be set up upright (cylinder head on), upside down (Cylinder head next) and transverse loading (toward the side of the cylinder head). The most common is the upright and transverse mounted. upside down starter is more difficult, and prone to oil and more. On-line manipulation of the model, especially on the control line stunt model in order to protect the engine, often with transverse mounted. Transverse engine is still a good start.

Small rc engine in practical applications, the problem may appear as well. So we need to often analysis, find out the reason, sum up the experience through practice.

3. maintain;

(1) keep the engine clean inside and outside, and never let the dus, paper, sawdust or other dirt from entering the internal. Engine when not, use a clean cloth or paper. After each use or flying, use clean paper or cloth to wipe them off of the engine outside and package; same time with a little gasoline or kerosene cloth to wipe off the oil on the model aircraft, with a dry cloth net. Do not drive much dust or sand on the ground or take-off; forced to take off in the sand on the ground, poured some water or pad some thick paper and wood to prevent sand from entering the engine. Do model airplanes often need to use the engine measuring the position and size of the intake and exhaust ports of the engine should be wrapped to prevent paper wood chips and other dirt from entering.
(2) Take care of the engine. Non-essential, do not use high-speed continuous drive, or use excessive short propeller and flywheel car. The regulator lever overextended.
(3) as much as possible not to dismantle or less demolished engine.
(4) To choose the right tools, the right propeller, the right ingredients and clean fuel.
(5) To contact with the rc engine oiling appliances often, tools and model aircraft to be kept clean. Should be ready a clean the locket specifically bloom oiling appliances, and Do not oiling appliances anywhere misplacing, so as not to the lime soil as the oiling enter engine. Lime soil as abrasives will quickly wear out the engine. Best the oiling of appliances, box, lecythus, and wrench on a specially prepared cloth or wooden box. Both convenient to use, but also to ensure cleaner, forgot some necessary tools to avoid going out flying.
4, Note safety - model aircraft engines, although very small, but the speed is high. Therefore, we should pay attention to safety, to prevent accidents.

After starting, do not stand in the plane of rotation of the propeller. Cannot use cracked or broken propeller goes for some and unbalanced, broken propeller decision cannot re-use gel. Never use metal propeller.

Do not close to high temperature or fire place when store the oil. Preparation of mixed oil and cleaning with gasoline engines, absolutely cannot smoke, and prevent smoking people closing. Do not open the rc engine indoors as much as possible to avoid the inhalation of ether and exhaust. Mixed lecythus outside must be marked toxic, so as to avoid misuse.Now i have told about many things aboutthe use of the rc gasoline engine and maybe you can see some of them from the online shop and sellers always write the use information in the production page. but i also hope it can give you some helps.

The life-span of the rc gasoline engine

  For a long time, I always wish to do a destructive test for the model engine, which to understand the life of the engine and the use of the gasoline engine's note. But it has been unable to do so due to time constraints.

  At the beginning of this year; I started the model engine ultimate test with everybody’s help. To ensure the fairness of the trial, I decided to buy the gasoline engine and fuel from the market at random, I bought a brand of the XL25 engine (4.07 ml) in a uk online shop; and bought 30 barrels of synthetic fuel containing 30% nitro methane of a domestic brand in Beijing; and purchased a domestic brand Heat for 10pcs, imported a brand # 8 Miami Heat for 6pcs. After everything ready, I came to the outskirts of Beijing to start the model engine limit test.

  The test procedure is as follows: Ground Engine Test procedure × × XL25 engine synthetic fuel test procedures:
1, using standard fuel (20% castor oil, 80% methanol) and 9 × 6APC paddle mill car 10 minutes.  
 (1) The medium speed for 5 minutes, then remove the engine for flushing.  
 (2) To mount on the engine, medium speed operation for 2 minutes; and then 3 minutes high-speed operation. Test the maximum speed record. Maximum speed tachometer highest reading in more than 10 consecutive seconds (same as below).   
(3) To remove the engine for flushing.
2, To use 30% synthetic fuel for continuous running test.   
(1) Medium speed operation for five minutes and then enters the high-speed operation, test the speed and record.  
 (2) Continuous high-speed operation for 4 hours. Check the engine and record.  
 (3) Continue 4 hours continuous high-speed operation. Check the engine and record.  
 (4) Every 4 hours continuous high-speed operation, until the engines abnormal.  
 (5) Each operation should test speed and record.  
 (6) Record total running time.

  In more than 83 hours of continuous operation, I feel that the biggest challenge is the vibration of the engine, it is recommended that prior to use of the new engine, the first to conduct a comprehensive inspection, each bolt to be tightened; propeller static balance; muffler should use704 silicone seal and reinforcement; using high nitro methane content fuel, plus a 0.05 to 0.1 mm cylinder head gasket. After the above, I believe that there will be unintended consequences.    The engine ultimate test is end, and I hope our work would achieve the effect forwarded.

  The test was on the afternoon of Tuesday, March 6, firstly, I use the standard fuel grinding car and then continuous operation assistant synthetic fuel with 30% nitro methane. The maximum gasoline engine speed is 14000rpm, cylinder head Heat head surface temperature is 165 ° C. The sound of the gasoline engine is fine, with some vibration. Principle analysis, due to the new engine cylinder piston is very tight, fuel content of nitro methane is high, but generally the engine compression ratio is low nitro methane or without nitro methane fuel designed for use. So the engine sometimes may cause the pre-ignition, and to cause the vibration. The normal measure is to increase the cylinder pad of a 0.05 to 0.1 mm. Because we want is the ultimate test, so I didn’t do so.

  To remove the cylinder head, found many pits on cylinder head and piston surface. Remove the cylinder and piston, many scratches on the side of the piston. Preliminary judgment that some granular foreign body inside the engine. Feeling crankshaft is still well-oiled, well-oiled between the connecting rod and the crank. Remove the crankshaft main bearing retainer pulverized about 10 mm, resulting in damage to the piston top and cylinder head. The engine continuous operated for 3 hours and 31 minutes this day.

  The ultimate test of the gasoline engine completed, accumulated working time of 83 hours 10 minutes, the flight of 12 minutes in each of the ups and downs, the equivalent of flying 415 flights. Above experiment illustrates the domestic life of the engine is still very high, the domestic gasoline engine has made substantial progress, more than some foreign brand-name products in the service life; domestic synthetic fuel lubricating effect is already full beyond traditional castor oil, and has reached the international the level of the famous brand of synthetic fuel. This is indeed a good sign for the China model airplane enthusiasts.

  Repaired for eight times due to gasoline engine failure parking during the test, the restructuring of the cylinder head bolts maximum workload. 3 of the Domestic Heat head damaged are all leak. Above inform that domestic engine reliability need to be improved. But honestly, the test conditions are really harsh, the engine is not designed to use high nitro methane fuel improvements (such as: plus cylinder head gasket, the use of "cold" Heat head), which can achieve such results really surprised me. Estimated that at current levels, if you use low-nitro methane synthetic fuel, its life is expected to be increased by 50% if used in conjunction with the the super lubricants repair fuel, engine life will improve exponentially.

Do you really know the led flashlight?

 Now more and more people used the led flashlight into the life.I think many people like buying the LED flashlight from the online shop and there are many choices for choosing. You always can choose the satisfying one.but now i do not want talk about it, i just tell you something about fundamental information of the led flashlight  and hope it is useful to you.Flashlight foundation affair: luminous body, the battery, the circuit, the housing, reflector cup, circuit positions, switches, etc. flashlight foundations affair out by the current from the battery, and then reaches the circuit, via the circuit to adjust the voltage and current, and then output to the light emitting body by the luminous body.

  Luminous body
 The flashlight light emission body are: Incandescent, LED and HID, LED brightness units unified with Lumen (Lumens) labeling, it is often said luminous flux.

  1、LED:
 
  Most popular LED full Chinese name is "light-emitting diode, small power LED are generally bulls used in 1AA or 3AA, I am not gone say much about this, in fact, too small power, can be use at home, but too weaker for outdoors, first and foremost to talk about more of a large power 3W outdoor use, the primary representatives present the most popular in the U.S. CREE LED, long life up to 100,000 hours, according to the manufacturer's data.

  Primary model parameters:
 P3，350mA  luminance 73.9-80.6Lumens，700mA  luminance 119.7-130.6Lumens.
 P4，350mA  luminance 80.6-87.4Lumens，700mA  luminance 130.6-141.6Lumens.
 Q2，350mA luminance87.4-93.9Lumens，700mA luminance141.6-152.1Lumens.
 Q3，350mA luminance93.9-100.4Lumens，700mA luminance152.1-162.6Lumens.
 Q4，350mA luminance100.4-107Lumens，The most current year night 1000mA.
 Q5，350mA luminance107-114Lumens，The most current year night1000mA.
 R2，The most current year night1000mA 1000mA.

Of course, they are lot of models, the commonly used is P4, Q2, Q5, of which the most popular at the moment than the Q5 a high efficiency, brightness, a large current to 1A, brightness up to 250 lumens. If you want a long-range floodlight with MC-E and P7, really good, for bicycles and urban lighting.

Halogen bulbs

   It was a lot on the market before the LED get popular, at moment it only few.Popular bulbs (incandescent). Needless to say this, the most representative is the Steller flashlight, Accompanied our growth at our Childhood, but a little bit behind the times, but as it is low-cost still has a lot of marker.

   Tungsten filament Xenon Xenon bulbs.

   The xenon filling inside, brightness forward a lot, the yellowish color of the light.Characterized by high brightness, but life is short, and it was up to 40 hours at the mercy.

HID  (The high pressure of the xenon gas discharge lamp)
 
  Xenon lamp inside the bulds, high-voltage lighting, ultrahigh brightness, power of common power of 10W, 24W, 35W, 1000-3000 lumens brightness maximum lamp life 3000 hours, LED flashlight focus leader. Interests a lot of errors fallacy: because the lights cups and Anjing identity, volume can not get down, the 18650 volume than the average single LED flashlight partial Eve, the most important is  "expensive", the cheapest is over 1000, not for average players spending.

battery
 
  The Common Flashlight battery are: AA (batteries), AAA (batteries), AA alkaline batteries usually can divided to dry batteries (1.5V) can not re-charge and the nickel-metal hydride battery (1.2V) can re-charge .

 There is a lithium battery voltage of 2.45-4.20V models 14500,16340,18650, many people see these figures is somewhat confusing, ask to distinguish, in fact, very simple, specific model numbers are for reasons, like 14,500  the diameter of it is 14 mm, the length is 50 mm; 16340 batteries is 16 mm in diameter, and is 34 mm in length, and so on, the 18650 battery is diameter 18 mm, length 65 mm.

  The lithium battery zoning care circuit (to prevent overcharge and over discharge circuit) masters should know that lithium batteries can not overcharge and over-discharge of the If the battery charge is full of power still in the chargerout come, but also to continue to charge occurs leaks or other adverse consequences; if over-discharge, the battery used to a little power still not charge, so that the city lead battery scrap the moment the installation of a care circuit will notthis problem, but many people mistakenly believe that the volume of a large, than without care circuit (Battery size on previous Paragraph) To Eve that add 1 millimeter or so in diameter, add 2 mm or so in length. Some difficulties, makes some LED flashlight put the battery bit difficult, ned slowly tempted to pot it in. However, the Eve the Ministry of flashlight is easily put to.

  And the battery in series parallel problem, Series current unchanged, the voltage is twice as before. Parallel voltage unchanged, the current is twice as before.

  If the battery with care circuit (with anti-overcharge and over-discharge) then you do not need read the  following describes as the  following main explain not care circuit lithium battery.

  New battery power is not too much; first use of the battery do not need charging too long, just need accordance with the charging indicator.

  While Charging, depend on the charger’s charging speed, when the indicator color change immediately took out the battery, not too filling, not  recommend charging time span 3-5 hours.

  Fully charged, the battery should be pulled out from the charger.Select the charger, it is best to use a charger with anti-overcharge.

  In use, need accordance with the torch battery voltage requirements, do not  use indiscriminately, to prevent burn the torch.

  In use, when the brightness of the led flashlight Earlier transition occurs is necessary to blockade the torch, to prevent over-discharge, (not the same mobile phone battery, used the phone automatically shut down, so that the battery will over-discharge, and can not be reused).

  Tips: During use of the torch to ensure normal cooling , use your hand is the best style. If is stood used, recommended to lit the torch often to dispel the heat.

  The torch when in use, it is recommended that blocked the torch every 30 minutes for 2-3 minutes, so can dispel the heat. hopes battery waterproof moisture resistance and other.

Electric circuit

  The battery can drive straight (which is directly connect the battery two wire link to the positive and negative LED connector) to a large LED's department, but the current is the same, there is a large cause smaller shorten the LED life light failure occurs, so moderation voltage and current flashlight dedicated circuit comes out, the circuits as below.

  Boost circuit. Mainly for use 1AA, 2AA battery flashlight, because the LED voltage is about 3.6, AA battery voltage 1.2-1.5, the voltage is not enough, you need the voltage to rise to 3.6 in order to make the LED work properly, it happened this circuit.

  The step-down circuit. Generally used in dual lithium flashlight on, like 2x16340 flashlight, LED operating voltage of 3.6, 2 x16340 series voltage 7.5V, the circuit output voltage drops to 3.6 for LED power supply.

  Automatic buck circuit. The name suggests is the output voltage drops below the operating voltage of the LED when the battery voltage is higher than the operating voltage of the LED when put hour LED operating voltage when the battery voltage is lower than the output voltage to rise to the working voltage of the LED, so it occurred to the constant pressure constant current, which is the best circuit.

LED   Flashlight, reflective Cup
 
  LED flashlight: High quality flashlight are aluminum alloy shell, almost the same material, the primary difference in the overview renew, generally the flashlight uses are popular oxidation renew, mainly black, gray. Some flashlight requires the ability to anti-wear and does not fade, it anodic oxidation, it will be no scratch even with life cutting, obviously, the price would be high.

  Lamp Cup. common have orange surface cup and glossy cup, orange cups overview bump refuses to accept, is characterized by a reflective average, the irradiation spot Peugeot; glossy Cup characterized by reflection high efficiency condensing function, but also is the long-range fate, but irradiation spot outer layer aura feels perfect.