If this does not fix the issue, it may be necessary to replace the whole starting rope system with another one. Replace the spark plug with a new identical. Drain and discard the old fuel, mix new fuel and cycle oil in the ratio 50:1 in a container, shake it and then pour the mixture into the chainsaws fuel tank. Most Stihl chainsaws have a resistance of 0.2-3.0 ohm on the primary coil and 5-20 kiloohm on the secondary coil but always confirm the correct reading for your model number. Mar 24, 2019. Use a brush and cloth to clean and remove any dirt, mud, or debris that can interfere with the controlsclean around the chain brake lever, the air filter housing, and the filter. Small Engine Technician Too much carbon will do that, check the piston top and combustion chamber. Also check the air filters and make sure they are clean. Neighbor brought me his Stihl MS250 complaining that it tries to pull his arm from socket when starting. Disengage the chain brake, turn on the ignition switch and install the new spark plug into the rubber connector. I hook up a drill to the nut on the clutch and start hard starting saws that way . It's an older saw I bought at a garage sale. Then Google decarb . After all these operations are carried out, it is necessary to once again clean the saw from dirt, then turn it upside down and unscrew the four screws securing the engine to the chainsaw body. Sounds like it was broken in "right", show the guy how to start it and tell him to be happy. I've done it to high hour Kohler engines many times. JavaScript is disabled. Low pressure, 20 to 30 pounds is all you need. If the chainsaw is too little compression, it may start easily but will not run smoothly. Apparently gas would seep int crankcase and over several months of setting gas would evaporate leaving oil behind and first time it was pulled would suck oil into the cylinder. Register today and take advantage of membership benefits. } Also take the spark plug out and do the same. Ron Cook. The following have been addressed. The plug should be tight against your thumb. The ideal pressure range of the Stihl chainsaw is between 90 and 110 psi. If it is hard to pull, then check how the spring is performing. Continue with Recommended Cookies. The spark arrestor in a chainsaw traps exhaust products emitted from an internal combustion engine. I;ve read somewhere to put water? Other than that, you should also use the correct spark plugs for your chainsaw. Also try removing the spark plug and see how pull starter works, just trying to see if it could be binding in the recoil/starter assy or not. If it is flooded that should clear it up. Sometimes, this might be triggered by another problem that is impacting your system. Also try removing the spark plug and see how pull starter works, just trying to see if it could be binding in the recoil/starter assy or not. Thanks. Low pressure, 20 to 30 pounds is all you need. I'll even do the labor for free. You can clean and mildly clogged carburetor but if it is too severe, replace it with one compatible with your chainsaw model. Over time or when using the wrong fuel, the fuel filter becomes too clogged and restricts fuel flow, killing the engine shortly after starting. The chain oil will keep the chain lubricated, keep off dirt and allow smooth movement. Do that to the starter side when you're looking at the starter assy. Carboned rings will decrease not increase compression. Unscrew the spark plug wrench using a spark plug from the engine. Thank you for the responses. If cleaning does not help release oil onto the bar, the pump may be damaged and require replacing. Additionally, most spark plugs come pre-gapped. "@type":"DiscussionForumPosting", { I used to have a Homelite that would do that if I left gas in it. Check the chainsaws fuel if you have not used the tool for a while. My one and only MS250 was a kicker to start it but that was the only problem. Free shipping. "userInteractionCount": 23 Below we have discussed the most common reasons why your chainsaw wont idle and the best way to fix it. By checking & repairing/replacing these, you can fix the issue. I would suspect the timing is too early. You are misunderstanding WHY water is put into carboned up engines. Poke the oil feed hole with a 16-gauge wire to unclog it until it slides through the hole smoothly. Quoting Removed, click Modern View to see Don't put water in the saw-ever. Keep in mind that the stuck ignition rope can also damaged other parts inside the starter assembly. Maybe take the plug out & pull the cord several times to blow out any excess fuel, then see how it pulls. Get you some Sea Foam at the local auto parts store. When this pressure, or compression, is too low or high, the chainsaw . It may not display this or other websites correctly. As far as compression, you can usually tell by how the saw pulls when starting it. Welcome! Try it, it may just do the trick! If you still have questions regarding high chainsaw compression, you can discuss them in the comments. Your ignition rope must be intact properly with the pulley to work correctly. Would not be afraid to do it to a 4, 6, or V-8. How does it feel with the spark plug removed? Try blowing the crankcase out with air. Use an adjustable wrench to loosen the two nuts on both sides of the chainsaw. Another big issue that causes too much high compression is the lack of oil in the starter system. Therefore, it does not need any compression rate to start. Temperature Of The Engine A heavy-duty engine gets hot faster and works better than a cold engine. How big a fella are ya? Remove The Chainsaw's Spark Plug Set The Pressure Test Gauge Tug On The Chainsaw's Starter Rope Reset The Chainsaw's Spark Plug Do The Thumb Test Remove The Spark Plug Place Your Thumb Over The Hole Tug On Your Chainsaw's Starter Rope Problems Caused By Too Little Or Too Much Compression Low pressure in a chainsaw High compression in a chainsaw In addition, you should check the muffler and piston while youre at this point. As the guide bar wears down with use, the bar heel- the part of the bar nearest to the drive sprocket- also wears down, which increases the distance the chain travels as the bar grooves become less effective. Check the choke of the chainsaws engine and make sure it is completely closed. I hope you understand the problems why your chainsaw is hard to pull. You are misunderstanding WHY water is put into carboned up engines. Hello EGBinOR, I will also add that if you have points, then the wrong gap will alter the point of ignition and can have the same results, Guido. If the chainsaw is too much compression, it may be difficult to start. Wipe off lubricant and grime from the bar with a clean rag. As stated it is with a hot engine so the water turns into steam in the cylinder and helps bust up the carbon. If this is the case, you may want to try lubricating the rope to see if it would assist to resolve the difficulties. Please use the navigational links to explore our website. Didnt somehow get straight oil in the cylinder did you? TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. Tighten the tension screw with a screwdriver to tighten the chain around the bar. "headline":"Chainsaw has too much compression", There are sprays (power tune) for removing carbon, but I doubt if that's your problem. Finally the fuel will be converted into energy. So, replacing the ignition rope is a better option to keep everything working smoothly without any damage. If it is not physically damaged, clean it with clean gasoline and a rag. The Stihl chainsaw is a two-stroke gas-powered tool that uses a substantial amount of compression to pull fuel from the tank, mix it with air and ignite it to produce energy that runs the chainsaw. I will also add that if you have points, then the wrong gap will alter the point of ignition and can have the same results. Get it ported and it brings it to another level. Wipe off the excess fuel from the spark plug with a clean rag. I would suspect the timing is too early. The early 064, 044, 066 came with a red master control. Sparkplug was correct but I think it was a little flooded. Repair or replace the damaged part 2. After that, using a ratchet, remove the spark plug from the engine. Sometimes the spring stops working correctly due to overuse and becomes brittle. And some will have more. The end of the tester must protrude exact the same volume into the cylinder as the spark plug or the reading will be wrong. Also, remove the muffler and check for carbon buildup. If not I'm honestly kinda stumped. 1. saw has new carb 2. flywheel has been removed and key inspected. If it does maybe it is plugged. NelsGarage will share the knowledge Ive gathered about different tools and give you tips to accomplish your DIY projects faster. However, if I push downward on the trigger button, it slows down to. Most fuels nowadays are a blend of ethanol which attracts moisture and speeds up the rotting process. In fact, Stihl thinks so highly of Motomix, that they will double the factory warranty on their Stihl 2-stroke tools if you use it. I've seen it happen a couple times. Then, use a wire brush to remove all the carbon build-up from the cylinder and piston. Detailed, well-researched, and accurate home and garden information presented in an understandable format is our primary goal. I would never put water in it! Are you sure the starter rope isn't a little too short? Turn off the choke by pressing the control lever to activate the fast idle. I have a MS250 that has come up on compression since new. Cleaned air filters and both were very dirty. "author": { When the oil pimp or oiler is faulty, it will reduce the chainsaws performance and power. When starting, slowly pull the rope to where it pulls hard before starting your actual starting pull. I pulled them over with plug out ,They seemed to pull normal and believe they were fuel locked. The Stihl 066 chainsaw uses the same type of engine most gasoline-powered yard tools use, a two-cycle combustion engine. Stihl recommends using 89 octane gasoline without ethanol, and the gas should not contain more than 10% ethanol. The exhaust side of the piston is a warm gold. stihl ms290 farm boss; By Ron Cook December 27, 2017 in General Chat. The excess gas can be cleared simply by removing the plug and operating the starter a few times. An excessive amount of compression in your chainsaws starting rope could also be indicated by the beginning rope failing to draw. Looks like a saw without base gasket, and too little squish my 250 did the same thing,had to start it with no choke.Take the plug out,crank it the motor and see how much gas spews from the cylinder.Mine would blow out way to much.I had to adjust the metering lever in the carb,no problems after that. The compression limit should also be doubled if the engine capacity is 100 CC. Check if the wires are damaged or broken and replace them if necessary. Has someone invented a new kind of two stroke motor? Loosen the nuts holding the clutch cover and disconnect the chain shroud and remove the oil plate. Change in temperatures and dirt will cause clogging anywhere the oil passes, and this can prevent the oil from spread all across the bar. "name": "Yesterday's Tractor Co.", Unscrew the spark plug using a ratchet and screw the compression gauge in its place. "interactionStatistic": { The spark plug is located in the engine and ignites the fuel and air mixture, driving the piston and running the engine. It had a compression release, and it started and ran well. It uncoils, tightens the spring, engages the clutch to start the engine. Starter fluids spray can help in those conditions Before pulling shoulder. Sometimes it kicks and the rope pulls right out of my hand. A clogged carburetor wont allow fuel into the engine, preventing it from starting. It's also going to be wise to try to put the chainsaw somewhere that isn't exposed to constant sunlight since that can be a contributing factor to the oxidation. Insert the air filter and the spark plug, reconnect the spark plug wire, and close the opening. I think that's what I'd do. Turn the brake off. }. There are sprays (power tune) for removing carbon, but I doubt if that's your problem. After initial pull on rope (which feels like vapor lock on cylinder), saw will start on second or third pull. The flywheel is loose? Have had it into dealer and nothing wrong with it and dealer said that from time to time they see saws come in with nothing wrong with them but have increased compression. Hold the saw firmly to the ground and crank the engine about four to six times to bleed out the fuel from the combustion chamber. The carburetor is a significant part of the chainsaw. Because of an absence of lubrication, the chain saw system becomes brittle, resulting in excessive compression of the chain saw mechanism. Create an account to follow your favorite communities and start taking part in conversations. Maybe take the plug out & pull the cord several times to blow out any excess fuel, then see how it pulls. Hello EGBinOR, I will also add that if you have points, then the wrong gap will alter the point of ignition and can have the same results, Guido. Not sure it would accomplish anything on a 2-stroke chain saw engine. check the cylinder & piston for carbon build-up, how much compression Does the chainsaw Engine need, How To Reset Echo 58-Volt Battery Charger. It is possible however to flood a two stroke which can cause the plug to fowl. Without proper compression, the engine will not be able to suck and use the fuel for combustion. It prevents the carburetor from allowing too much fuel into the combustion chamber. As the chain moves over the bar, it spreads the oil across the moving parts to reduce friction and heat. Little two stroke motors as on chainsaws have to have a lot of compression to make the needed power. Most of the time, the chainsaw cord became hard to pull because of the Starter Housing. We will explain the causes of high compression and how you can quickly fix it to make it run smoothly. To inspect the guide bar, disassemble the chain cover, chain and bar. It would give you rusted bearings. Clean any mildly dirty parts and replace all the damaged parts. I usual only choke my MS250 for one pull and no longer have the flooding issue. Once it's removed, you can place a gauge on the place of the spark plug. This could be understood by reading the further explanation below. Once the 250 is running, its fine. A reddit for all operators of chainsaws to post experience with tools, pictures of their new saws and old workhorses and any maintenance tips. As stated it is with a hot engine so the water turns into steam in the cylinder and helps bust up the carbon. "publisher": { That is the nature of a 250. I bought 2 032 Stihl saws at auction that pulled very hard. Maybe take the plug out & pull the cord several times to blow out any excess fuel, then see how it pulls. Flooding usually happens due to an underlying issue: a bad spark plug, bad gas, or a faulty carburetor. If you regularly use the chainsaw, then there might be the possibility that your starter spring breaks off. There are sprays (power tune) for removing carbon, but I doubt if that's your problem. Would have to remove spark plug and rinse cylinder with gas to be able to start. When the spark plug is removed, the engine turns Ask an Expert Car Questions Small Engine Troubleshooting JON, Small Engine Technician 2,680 Satisfied Customers Certified Small Engine Technician JON is online now Related Small Engine Questions Help, can't pull start Stihl MS250 chainsaw, too much compression. Replace with a new starter house Problem 2: Damaged pulley system Solution: 1. Chainsaw Parts. Dust particles in the air mix with the lubricating oil and clog up the air filter, therefore, preventing sufficient air from getting into the engine. If you experience low compression, pull the muffler and check the piston and cylinder for, Read More How Much Compression Should a Chainsaw HaveContinue, The possible reasons can be the battery not being charged, properly connected, or dead. Dont substitute it with. Just wondering what your opinions are of the lowest compression you can run a Stihl MS250 at. Try it, it may just do the trick! Subsequent starts are just as hard. Maybe the piston is hitting it. #1. It is best to put a new plug in after clearing. Remove ignition coil and muffler. For the chainsaw to function appropriately, you must maintain the proper amount of tension on the chain. You can unclog the carburetor if the clog is minor. I have had the cylinder off. i have a ms 250. "@id":"https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=toolt&th=435118", Create an account to follow your favorite communities and start taking part in conversations. idle. Manual for my Stihl saws and leaf blower says to scrape carbon out of the exhaust port. When you are doing a cold start, push the choke lever to the warm start when the engine starts to run. Too much hot or cold engine does not work or even start to produce vacuum pressure inside engine. JavaScript is disabled. Stihl MS290 MS390 MS310 Chainsaw Has Oil Tank Engine Housing Assembly OEM/ Bin G . Locate the spark plug from the top of the engine underneath the chain brake handle. Generally covering everything under 25 HP. This Indoor Fly Traps: 5 Things You Didn't Know About Indoor Fly Traps. If you introduce an extremely fine trickle of water into a running engine through the carburettor that may remove some carbon . I pulled them over with plug out ,They seemed to pull normal and believe they were fuel locked. "description":"Discussion of Chainsaw has too much compression in the Tool Talk forum followed by comments. Now, the gauge might come in a number of size variations, so you need to use an adapter to make a perfect seal between the gauge and the chainsaw. Stihl 251 chainsaw. To clean it, drain the fuel, spray some carburetor cleaner and loosen the residue with a small brush. As a result, normal compression settings will change based on the kind of chainsaw machine you are using. Cleaned it all up, and had it tuned up. All it needs is a few inches missing and it will pull too hard like the compression is too high. or Best . Getting these problems resolved is a rather straightforward process. Oct 24, 2011 / Chainsaw excessive compression #1 . A lot of variables might contribute to excessive compression while using a chainsaw. Ok folks, I'm stumped. If you notice the treads are worn, which prevents the device from pumping, replace it with a new one. By rejecting non-essential cookies, Reddit may still use certain cookies to ensure the proper functionality of our platform. If the chainsaw wont stay running when the engine is idle, adjust the carburetor. So be sure to keep your chainsaw properly maintained and avoid compression problems. ", I went with a meteor piston/cylinder set. Little two stroke motors as on chainsaws have to have a lot of compression to make the needed power. water will not dissolve carbon; it is far too hard to be effected. While rope attached to a pulley, the further connection of the pulley is with springs and pawl to make sure the pulley is tensioned and helps in retracting and spinning. The power of the motor of an engine is measured in its capacity. I have a MS250 that has come up on compression since new. The engine must be up to operating temperature, spray a light stream of water into the engine carb air inlet and the cold water shocks the hot carbon and the carbon flakes off and blows out the exhaust pipe. I bought an old beater 621 Jonsered once that had very high compression, got it running well and sold it, made some money on it! "@type": "ImageObject", When the motor warms up after about a minute, turn on the choke position. Sometimes, the ignition rope is frayed or stuck inside the starter housing. You can prevent the new starter rope from fraying by burning the two ends of the rope. This is bad practice, and can damage your chainsaw. It is typical for the Stihl chainsaw to develop some issues, and when this happens, some basic troubleshooting will help identify the source of the issue and solution to help it run smoothly. If I drop start it I can pull it through 1 compression stroke. Find the low speed, high speed, and idle speed screws near the carburetor, start the engine and allow it to warm up. A compression gauge is used to measure the compression of a chainsaw which works similarly to the tire gauge. You need to pull the exhaust to check that. By rejecting non-essential cookies, Reddit may still use certain cookies to ensure the proper functionality of our platform. It runs good after I get it started. I would suspect the timing is too early. "text": "My chainsaw has gotten very hard to pull the rope. John Deere and its logos are the registered trademarks of the John Deere Corporation. That is a high compression saw, pull the rope slowly until you feel resistance then give it a short quick pull. Blup throttle to bring it down to idle. If you are trying to start your chainsaw in winter and the oil you used for the chainsaw assembly is not suitable for the winter season, you also feel high compression. Advanced arborist chainsaw with a top handle and STIHL M-Tronic technology. Yeah, I must have flooded it as I was working on it. link to Winterize Your Pool Like a Pro: A Comprehensive Guide for Home owners. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. To fix this problem, turn off the chain saw and let it sit for about 30 minutes to allow the excess gas to evaporate. Wash the dirty filter with a non-abrasive detergent and water. A smaller gap will cause a weak spark and poor ignition of the engine, while a wider gap will not bring out any spark. Now, how much compression the engine of a chainsaw needs depends upon its motor capacity and temperature. 3 9 9 comments Best Add a Comment Revolutionary-Act469 2 yr. ago Doesn't pull at all or just hard to pull. Soaking in water will do nothing but rust things up . in the, All Rights Reserved. It is possible however to flood a two stroke which can cause the plug to fowl. Wear rubber gloves and hold the rubber plug and spark plug about 1-2cm from the metal surface of the engine unit. Save my name, email, and website in this browser for the next time I comment. Have had it into dealer and nothing wrong with it and dealer said that from time to time they see saws come in with nothing wrong with them but have increased compression. I would never put water in it! We are compensated for referring traffic and business to Amazon and other companies linked to on this site. If that doesnt work, try gently tapping on the side of the bulb with a screwdriver or other tool. I think that's what I'd do. If you still want to try and get carbon out of the saw either take it apart and clean it or use something along the lines of sea foam. Can also be used with hedge trimmer attachment HS 246. A heavy-duty engine gets hot faster and works better than a cold engine. Hello EGBinOR, If A two cycle engine gets flooded BADLY, oil can separate from the gas mix, accumulate in the crankcase and creates an hydrostatc lock. It is effortless to check the starter spring; pull the ignition rope. First thing I'd check is the pull start assy. Any ideas? If any of these components are worn or broken, the chain saw wont start even with fuel. Could be the main bearings are loose, look for evidence of the coil rubbing the flywheel. Manage Settings } My husky 266xp has been that away from newjust pull over slow for 2 or 3 times and then try cranking.. Ivor from uk here and I have a stihl chainsaw and when I am hedge laying or pletching as it is called the saw only runs for 15 or 20 seconds or perhaps 1 minute at the most if there is a big cut to make the spark plug tip builds up with carbon,i use proper 2 stroke oil at a ratio of 25to1 does any pletching or hedge laying go on across the pond??