How to Diagnose Two-Cycle/Two-Stroke Engines

[@youngcameracompany]

This video should be required viewing for all High School students. Everyone should know these principles. They were presented in a clear, concise and easy to understand form. Thank you.

[@brandonroussell9552]

i could never smile as much as this guy while working on broken equipment lol...

[@lmstech]

excellent. after playing around with engines for 50 years, and reading books, your video just made it all make sense, once and for all. thanks

[@Anhedonia411]

I love how he used Carb Cleaner as Starter Fluid. Learn something everyday.

[@kittylovermybut]

+1487G Yeah the active ingredient in Carb Cleaner is Heptane. Its pretty darn close to the active ingredient in modern starting fluid and it will get you out of a pinch. PB's rust buster also works. Never use WD-40 though.

[@allenbrown2176]

I am doing a lesson on two cycle engines for school and I thought that the information provided was very beneficial for any homeowner that uses any two cycle engine.

[@brew4953]

Hey Mark, Dont forget the kill switch wire that goes to the coil,Ive sometimes had those ground out making it seem like a bad coil,And sometimes the kill switch itself will be bad. Knowledge is Power.

[@wisestudent1463]

I have worked with 2-cycle engines for many years...But this video is most informative and helpful !!

[@FIXTechGuides]

It sounds like there is still some debris in the carb. If you can get your hands on an ultrasonic cleaner they do wonders to clean stubborn carbs. You can also try using fishing line to clean the small passages in the carb. Never use anything metal though to clean. The metal will damage the fine passages and the carb will not work properly afterward. I hope this helps, -Mark

[@Nifty-Stuff]

Mark, you do a BRILLIANT job with these videos! You obviously know your stuff and present the information exceptionally well! I've had a handful of gas trimmer problems and I know I can count on your videos and your friendly / cheerful disposition to solve my problems. eReplacementParts did a great job having you do these videos!

[@schmittenhammer]

I have very poor hearing, and I found your video very clear. Also instructions were clear and straightforward, a great help, thank you!

[@schmittenhammer]

Pat Nugent Since retiring, I have been fixing things that are broken. My sons are supplying me with various tools they own. Chainsaws, air compressors, weed eaters. I helped my oldest son fix an electric dryer and when he saw how simple it was, he has helped fix a couple for his friends. With the new smart phones (I don't own one) you can just get on KZbin and punch in an appliance and most likely they have a video that will diagnose and tell you how to repair it, while you are standing next to the appliance, it is amazing! I fixed a non-working NuWave oven (cost $150) for less than two dollars!! Amazes me how many people throw things away that are fairly simple to fix. But I realize not everyone has the same interest or talents.

[@schmittenhammer]

Steve Schuller so do you have the rest of the deck I am missing? Many say I ain't a playin' with a whole deck.

[@FIXTechGuides]

Thank you! We appreciate your business and words of praise. -Mark

[@arthuramerine2742]

Mark I work for The Home Depot as a tool tech I get a lot of parts from you guys, I find your videos very helpful. Thanks Slot Tim

[@FIXTechGuides]

@spelunkerd We had a saying at the small engine shop I used to work at. "Everything gets a plug!". It would cost the customer less to simply replace the plug rather than starting a time consuming diagnosis. If the engine still won't run then we would pull out the spark tester. The tester I used in the video can give a false positive like you mentioned. There are other types though that can be grounded to the engine block, bypassing the plug. Thanks for watching, -Mark

[@richardgibson50]

Mark, loved your thorough video on checking for problems for 2 cycle engines. I am going to use what you taught me to check for problems on my Poulan leaf blower. Thank you very much.

[@rodneyjackson622]

This made me more knowledgeable about, how to fix my machine. I am thank fore for this timely information.

[@stevefoxon6742]

Very useful and very informative. You manage to take a lot of the mystery out of these tasks and your explanations are simple and clear to understand, they are a great help, especially to the keen amateur. Thank you.

[@dochlee1]

Very logical step by step explanation to trouble shoot the problem. Needs the right tools to get the right result!

[@AltonRowell-gb1lb]

Anouther great video. Thanks for your help.

[@bpekhoul]

Thank you so much for your explicit explanation. Excellent presentation. Thanks for unselfishly sharing your knowledge.

[@micklavo9204]

This video is brilliant and very helpful. Very nice and professional presented

[@jimdidonato1246]

Nice job! Good pace, good coverage, and good shots of the equipment.

[@reginaldharrison8458]

This is the best explained video on youtube great job.

[@tminceb]

Thank you Mark, perfect balance between high level diagnosis and detailed direction. Add a sprinkling of common sense eg electric problem - replace the spark first

[@reactiontvchannel.2339]

Who's watching this 2020? Thank you, I'm fixing my trimmer, right now

[@thecbc7658]

Loved the video straight forward and in depth and with a variety of equipment. You should do a video on how to increase the performance of a two stroke engine

[@johnthatcher5225]

This was just what I needed. I fixed my trimmer and leaf blower. Thanks for the valuable information.

[@henrylama7861]

Very good, clear speaking and the best school ever in youtube. That's simple like that!

[@blindcuckoo6680]

great video, really helpful rather than guessing what the problem is.

[@BernhardHofmann]

Superb videos. You're very clear and well paced in your delivery and you smile a lot. :)

[@1musicsearcher]

Nice clear diagnostic video. Now to tear into my trimmer. Lots of little pieces‼️

[@dollymarcum7258]

W-40 is the best starter fluid for a two-cycle engine,with out risk of blowing it up or scoreing the rings,FYI,Good Video!

[@connorking7785]

Mark seems like a great person! Thanks.

[@tobbo166]

Really good video! Very pedagogical! Keep up the good work!

[@KabeloNgwenya]

BRILLIANTLY MADE. CLEARLY EXPLAINED: THANKS FOR THE HELP :) I'LL BE BACK TO POST A QUESTION SHOULD I RUN INTO FURTHER DIFFICULTY AFTER TRYING THESE METHODS

[@newcoyote]

This is of course the correct way to do it. Dang it if EVERY time I have a machine go down in the field, it is some obscure, deep hidden glitch. "The most common..." does not seem to apply in the real world.

[@BenKingEagles]

Thank you, this video was VERY clear and simple to follow. I've worked on my cars and on my bikes (very complicated!) and in my many years of doing lawn maintenance I've been hesitant to bother working on my equipment. Tbh, it was a huge job on my V4 Magna that convinced me a small 2 stroke was simple by comparison. :)

[@michaeldowling5357]

Thanks for the clear, professional advice.

[@duanemiller3304]

Great video! What am I missing? Echo PB 200 blower. New spark plug and strong spark with Oppama tester, new carburetor, fresh gas 50:1, new fuel lines/filter, compression = 90+, spark arrestor clean. Get a pop with starter fluid, but can't get it running. Already bought a new one, just the challenge of trying figure this one out.

[@goodgirl99us]

Duane Miller check you carb adjustment screws, or check the needle valve for proper operation. sounds like your not getting fuel. also if its an older model exhaust can build up soot from running improper oil mix clogging the muffler seen a few but not that common.

[@duanemiller3304]

Thanks, Raguel Bauman. I agree, has to be a fuel issue - just can't find it yet. Gonna go back out there right now and go through the whole fuel system again.

[@lmalino695]

+Duane Miller If only a pop, and not actually running, on starter fluid, may be timing is off.

[@theellisonparkgarage2519]

+Duane Miller Try running it with the gas cap off. Does it run and stay running?

[@larryallen6492]

Good info, I have repaired many 2 cycles but the compression info was new to me. Thanks

[@209Twinz209]

Helpful. Diognosing a 2 stroke dirtbike now with the help of this vid. I am a first time owner an not super mech inclined. I feel a lot better knowing about how to properly diagnose a prob

[@superatech]

Hi Mark, I think your videos are very intelligently presented. I have a question. If the engine starts when you spray starter fluid into the carburetor, then isn't the carburetor okay? Doesn't that mean that the problem is the delivery of the fuel TO the carburetor that's the problem? Thank you.

[@douglasmcneish1880]

Mark dose a very good job getting through the process of 2 cycle engines i learned quite Thank you Douglas

[@petefrederick5362]

Very good video, Thank-you. Looks like I am heading down to Canadian Tire to buy some starter fluid. I like how you simplified your analytical approach in diagnosing the problem. Priceless! Cheers.

[@AWelter750]

Great videos mark! I'm trying to tackle my first small engine issue (weed eater) and your videos are by far the easiest to understand and the most helpful.

[@DONphantasmo]

Great video. Very well put together. Honestly I knew most of that info, but the way you put it, just made even more sense. Good job!!!!

[@ronneyharding4675]

Great video.Concise and put in laymens terms.Thanks

[@hokieinidaho]

I found this video to be very educational the way you broke up the analysis into a systematic approach. Wish I'd seen this a couple of years ago. Great job!

[@shadovanish]

Great video! On my weed eater, I experienced a low power condition with the engine, which was caused by a poorly sealing crankcase cover gasket on one occasion, & a carbon fouled muffler on another occasion. The poor crankcase seal resulted in low compression in the crankcase, which allowed the fuel air mix to leak out instead of going into the combustion chamber, & the carbon fouled muffler did not allow for good exhaust flow, thus reducing engine power.

[@FIXTechGuides]

The most likely cause of this would be low compression due to worn piston rings or a worn or damaged cylinder. Start with a compression test. Anything less than about 70psi would be considered low. Hope this helps, -Mark

[@eclipser2004]

Thanks for the help. I have a Poulan 2150 chainsaw 36cc 2-stroke. Worked perfect 2 days then would not start the third. It appears to have spark and compression. Tried a new plug gapped to 0.020" but not a gig. I guess I will clean the carb, but starter fluid/carb cleaner did not work to fire it for even a second. The plug does appear to be wet with gas after I pull it a dozen times but I will clean it and the fuel filter too. I guess if that does not work I will try a spark tester.

[@LarussDecrepit]

As a processional small engine technician with over 50 years of mechanical expertise I find this video to have some flaws in your two-cycle troubleshooting. Due to the limited space allowed I cannot post them all. Overall though I have to say it is a good video even if it is still incomplete.

[@UmutUnver]

Thanks for video. It is very easy to follow and very useful.

[@kenjiwawa09]

thank you sir you really really educated me on something I had no idea of.. but everyone else did.!

[@m0j0b0ne]

Excellent! Got right to the point, but left me a bit confused as to what is indicated by too much compression. I'm guessing that could be friction/pitting from running too lean a mixture or gummy residue buildup?

[@kodibassInsideoutboards]

I have a husky chainsaw that has over 150 psi, what causes high compression? I hate starting this saw, Does this indicate a problem? Great vid.

[@FIXTechGuides]

Either starter fluid or carb cleaner will work fine to perform the fuel delivery test. I have always used carb cleaner simply because we use carb cleaner for many cleaning tasks in the shop. There is always a can of it nearby. Thanks for watching! -Mark

[@micklavo9204]

Hi Mark is pleasure to watching your video. Very useful and very nice presented. You got the skill to pass the knowledge to people! Gratulation!!

[@timmcnemar3910]

Thanks for the videos they are very helpful.

[@r-n-jhomesteadlife4800]

Awesome Video. My teen son in getting into small engine repair, this will be great for him. Thanks

[@chuknoariss4342]

Well done a lot of the help videos I see on KZbin are filled with umm and it might be... but this has definitive answers thank you for your quality video!!

[@birdog6668]

i have a husqvarna 128 L D weedeater it is about 2 years old. . it will run for about 15 seconds on full throttle and then dies. If if leave it on half chock it will run longer before it dies. I thought it may be a vacuum problem from the gas cap vent, so i removed the cap completely and still have the same problem. It was running great until one day the spark plug became loose. I removed the plug and found the plug was loose in the center of the plug. I install a new plug and ever since i have had the problem. Thanks for the video they are great

[@dav3fk]

If you mean you still have the problem with a new plug, fuel pump (in the carb) I should think. I suggest you service it at your nearest dumpster.

[@gatorfan3032]

Very good information and very helpful. Thanks for taking the time to do these videos.

[@laurijorgenson6683]

Great video. Very helpful in diagnosing small engines.

[@awalt26439]

A well thought out and well organized tutorial. Thank you.

[@brainfeed6604]

Great info ,I own a stihl brush cutter and when I give it more throttle it doesn't seem to cut off or slow down,and when it starts the spool spins when I ain`t touching the throttle`so I adjust the throttle cable and it struggles to rotate fast and cuts out,any add vice please on these matter,owe yes I have checked the baffler and it seems it seems to be good,

[@grahamparent7876]

Great videos. Very well written and informative.

[@philipingram1667]

Well done - good information on diagnostics

[@plantearly]

Very well done. I've added you to my library.

[@GetItDoneProjects]

Thanks for the helpful, methodical approach. I'll begin testing today.

[@chipbanks6823]

Super video. Very informative & clear cut instructions. Thank you for separating the systems. Including the links was helpful.

[@FIXTechGuides]

Most auto parts stores offer ignition testers. I purchased mine from my local Snap-on dealer. Thanks for watching, -Mark

[@jimlights1607]

top video so easy to understand- a real skill in communicating my prob is my strimmer will only run on half choke ay ideas? cheers jo

[@spelunkerd]

That's a really good summary, Mark. I was interested to learn that you feel a spark tester is a more reliable index of adequate spark than is pulling a plug and grounding to chassis, and watching for spark there. But what if the plug is bad? If the plug is shorted then I would expect a spark tester to give a false positive, since current is flowing, albeit on an aberrant pathway. I' e never used a spark tester like yours but I'll consider getting one after watching this.

[@learningisgrowing]

Excellent video in all respects. Great job

[@soundmiami]

Considering the $150- $200 cost of replacement it's unlikely I'm going in as deep as new rings on a little chainsaw, but your starter fluid, and a new plug is a $5 very doable pre hurricane field test ritual. Thanks

[@fotlitbowfotlitbow5514]

It has been the case with me that I have experienced many fuel delivery system failures never requiring a carb clean or rebuild. 15 to 1 my issues are in gas filters inside the tank, fuel lines or primer bulbs. You might want to add a word about them. It just a thought.

[@FIXTechGuides]

That's a great point! We're always open to suggestions from our viewers, and we put out brand new videos each and every weekday. Thank you for the advice, and don't forget, you can subscribe to our channel and get access to all our new content, some of which based on viewers like you!

[@josephlypowy7389]

Great information! Useful and educational.

[@FIXTechGuides]

First thought would be a plugged spark arrestor. See our video titled "How to Clean the Spark Arrestor on a Small Two-Cycle Engine". If the arrestor looks good then you will likely need to rebuild the carburetor. Take a look at our video titled "How to Rebuild a Two-Cycle/Two-Stroke Engine Carburetor". I hope this helps, -Mark

[@alonhudson4664]

i have a troybuild weedeater it starts fine and idles but as soon as its revved up it cuts off i have replaced lines, line filter, primer bulb and spark plug also new gas also cleaned carb checked muffler for clogs sso what now?

[@miltonhusky]

Well done nice video a very pleasant demeanor . Informative steps in diagnosing a problem

[@TerryToon17]

Hi Mark, I have an Echo PB1000 blower, I used a spark tester (as you suggested) and the ignition is fine. If I spray starter fluid in the carb, It does not fire, I tested the compression and it is 80 PSI and raises to 115 if I put a little oil in the cylinder. I am thinking it may be a crank shaft seal or a leaking crankcase, but I have not removed all the plastic casing yet. Is 80 PSI to low Your thoughts?

[@varadamurthysrinivasan2136]

Brilliant video Mark. I have a Craftsman leaf blower (2-cycle) that is having a a compression of less than 70 pounds. I heard that engine restore lubricant can bring back compression back to normal. Can I use that in 2-cycle engines and if so where would I add the oil? Thanks in advance for your help...

[@filmifymylife]

That was super helpful. Thanks! I'm glad this video exists! I wish I looked at it awhile ago!

[@Tnblues100]

good clear ,concise instructions thank you.

[@skipwavedx5151]

I have a question about the spark tester, since it is inline with the sparkplug one must assume the sparkplug is new. I have here a sparkplug that is wide open when you measure it on a ohm meter and I thought my coil was bad.

[@FIXTechGuides]

No, the spark tester only tests the ignition coil. If there is any suspicion of a bad plug the easiest thing to do is simply replace the plug. -Mark

[@playit00]

Hi! I have a yard machine weed trimmer and I can't get it started. I changed the spark plug and didn't start. I then noticed the primer bulb sticking and changed that. Still sticking when I push it in. I was going to change the fuel filter but I don't even see one in the tank. Not sure what to try now. Any suggestions would be appreciated. Great video! I wish I would have found this earlier before changing those parts. I've got to try spraying the carb cleaner and see if it fires. What else is left to change? Please help!

[@FIXTechGuides]

Most auto parts stores sell them. I purchased mine from my local Snap-on dealer. I think I payed about $15 for the one I use. Thanks, -Mark

[@braulioperez181]

thanks for such interesting video. These videos are an excellent marketing tool for your company. Please keep them up.

[@stephenchong1343]

excellent video. I have a Craftman WeedwackerC944,517360, do you have a video to show repair of carb? Any directions is greatly appreciated.

[@MrJose1223]

Great video . For a compression test is that tool used on the regular engine .

[@mihaiborz3812]

very useful video very good info and well explained

[@berkeleyversusocoee]

I just eat this stuff up! really helps me...as do the comments below...because I don't know (or once didn't know) anything about two-cycle! ME! A kid born in Dayton, Ohio, home of the Wright Brothers and their 1903 original aeroplane (which was, ahem, two-cycle!).

[@erndog64]

Nice video!! Straight forward and clear instructions!!! Thanks!!

[@TheCountaaron]

this video was extremely helpful. what did people do before youtube!?

[@whowantstoknowido]

Great video,thanks. One point though I think you might be better putting a small amount of pre-mix in the carb rather than starter fluid. Starter fluid will make the motor rev up for a few moments with no lubrication from the fuel.Not a problem with a four stroke but ...

[@bruno1999]

That was the best video ever, sir! Great teaching and explanations. I was about ready to just go buy a new trimmer. THANK YOU!!!!

[@woodbarter5713]

My 395XP sat for 3 years non use. Wouldn't start so I put a carb kit in it. Still won't fire up. Used some starter fluid still no go. Getting a nice bright blue spark in the plug (old school testing wired to the jug). Getting fuel and fire but hitting a lick. Scratching my head. Haven't done compression test yet but feeling plenty of compression when I pull without decomp valve depressed. Compression check is next anyway just to be sure I guess but not very many hours on this saw.

[@CHIBA280CRV]

Excellent tutorial , thank you ...

[@JustMeNoOther]

Hi, please could you tell me what is the best spark tester? because I need one, and more if this test the status of the ignition coil. Tanks!