Husqvarna 345 Engine Rebuild – Cylinder, Piston & Ring Replacement

In this video I show you how to rebuild the “TOP END” by replacing the cylinder piston and ring on a Husqvarna 345 chainsaw.

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46 thoughts on “Husqvarna 345 Engine Rebuild – Cylinder, Piston & Ring Replacement

  1. Really nice job man .. I would like to mention that if most of the substandard finish work with the new barrel is a problem for you theres alot of improvement to be had in the use of a die grinder and a cartridge roll for finishing .. even the stock barrel had about 1/8 inch of material that could have been port matched on the exhaust side.. there is tons of power to be gained from a bit of smoothing of the ports .. I wont get into changing transfer port height or size as a means to make power .. but you could improve the saws power 25 percent or more from port matching and smoothing .. love your channel nice job

  2. Hey Dony, Great videos! I have a questions How do you know what is the correct compression on chainsaws? do you have some kind of chart that tells you what the compression rang is? I have a Husy 445 with a scored piston doesn't look too bad has a compression of 115 psi and it runs but I'm not sure whats the correct PSI.If you could help me out on how to find our what the correct PSI is. Also I have another Husy 455 Rancher and reads a 120 PSI and runs good but again not sure if that psi is right. I' have been looking for some kind of compression PSI chart from Husqvarna but can't find anything. Thanks keep up on the videos!

  3. thanks for the response do you know a good place to find service repair manuals online? thanks for the info, so 45cc and a 50cc will both have a compression of 150+ psi?

  4. Thank you for your great teaching. I am able to repair other peoples machines watching yours. I also send people to your pages. Where you trained in school or are you taught by someone or self taught? Thanks again and Happy New Year.

  5. Don, great video as usual. I look forward to watching your videos. Looking at your hat,are you in Muskokas? If you were closer to Ottawa I would bring my Husqvarna 254XP and leaf blower that are both not starting to you. You should look into teaching small engine repair,you would be good.

  6. This is a great video. Great detail and a lot of necessary information. Thanks Donyboy73. Always like to visit your page!

  7. So looks like i my be wrong!
    I may be wrong about this also, "those two parts do not get installed WITH THAT KIT at all"
    But I am very thankful for the very well put together video and you do nice clean work.
    Next time you get one of those kits look at what I thinking.
    Thanks again!

  8. hi I got a husky 240 the saw had a lot of problems it sheared off the flywheel replaced that it had engine problem I took apart and it had a broken ring I seen the plastic on each side of the cylinder they are loose I don't know about that is there any other cylinder I can use to replace that plastic stuff I have a 365 special excellent saw this 240 what a mess nice videos I watch them all got any ideas bob in pa thanx

  9. I get this is kinda old but, you said in a video that the saw should not fall when holding by the pull cord but if the saw is made fully out of die cast magnesium that does not apply right?

  10. Hello Dony from New Zealand, love your work matey. I have a Husqvarna
    36, beautiful saw. The problem i'm having is when its hot, I find that
    the kill switch doesnt always work and I was wondering if its possibly
    due to a faulty switch, or could it be the ignition coil/module causing
    it not to stop? It certainly runs well all the time, its only when its
    hot, it wont die by kill switch. Look forward to your answer. Many
    thanks, Phil 🙂

  11. Simple question as I prepare to do my first top end rebuild of my 350: My cylinder kit came with seals. Do I still use the sealant with the seals?

  12. Hello Don,

    I have the Husqvarna 345 chainsaw and have been using it for 6 or 7 years. The 345 is a real performer and whether I use it for 2 hours or 8 hours it's never failed to impress me.

    I enjoy your videos a great deal. I like the way you explain everything clearly and using your videos as a complete guide have been a great learning tool saving me quite a bit of hard earned money.

    Thank you and keep up the great work!



  13. Fantastic video! Thanks for posting.
    Question: When reassembling after cleaning, should we place some oil in the lower crankcase ? (if so, how much are we talking and which viscosity of oil?)

  14. Excellent video; did cylinder & piston on Mac 335 using this guide. Tips: put the gudgeon pin in the freezer and warm the piston (I put it a jar in some hot water) then the pin can be pushed all the way in with your little finger; grease on the rings will keep them in the right place as the piston is pushed into the cylinder (the new cylinder was coned so did not have to squeeze rings).

  15. Thank you so much for all of your videos on rebuilding chainsaws. I have a Husqvarna 261 from 1999 which has performed well over the years but recently I've noticed it has a lack of power. After a compression test I only got 115 PSI. So I bought a top-end rebuild kit off Amazon for $100. The cylinder and piston are from Taiwan. Watching your video and following your instructions I was able to tear down my saw, clean everything in the parts washer, and reassemble the saw with the new cylinder and piston. It looks and runs like a new saw again!! Now I'm getting just over 150 PSI on the compression test. Without your videos I would never have attempted this on my own. THANKS!!

  16. dony, I have a 346xp I just put a new cylinder and piston on it(used echo red armor oil to coat the piston,rings,cylinder) and for the life of me can't get it to start even with fuel and spark. would you have any ideas on what it could be? I checked and didn't see any scoring on the new cylinder and no air leaks on the crank seals.

  17. Hey Dony do you know what serial this 345 is? Mine is the exact one can not find the serial must be inside. But I need to replace a broken gas cap and my local shop is full of idiots giving me the wrong size and they don't know how to order the right one online. Go figure. Thanks

  18. I will never try to do that assembly because, I will not remember how to put everything back together.again. I wouldn't have believed it if I didn't see it being put back together. Excellent small engine doctor you are and I don't think it get's any better than that.

  19. Good work. What would u say your parts cost was for what you did. Obviously labor,, if you had a shop do it,, wouldn't make it worthwhile . But if you did it yourself,, probably would. Thanks for your video.

  20. Do you have experience with the Echo cs 300 series? running cruddy and was curious,,, heard something about fuel tank venting? Wondering if grime in vents above pull start affects fuel vent tube. thanks

  21. Hey Donny, I have a problem with 576XP just topped gas tank up with straight gas by mistake (never done this stupid thing before) tank had maybe 1/3rd tank of mix in it before I topped it up, it ran for 4 minutes or so and conked out, that was my warning sign but I didn't realise, I restarted it and ran for 1 more minute and it just seized and now cant pull cord at all, saw was cold when I started it and ran for total of 5 mins, so whats the likely damage. I haven't pulled the muffler off yet. You mention straight gas damage is no compression. why do you think mine seized ? Thanks in advance 😉

  22. In Australia it's cheaper to throw away the chain saw if you have to replace a barrel and piston. The barrel on it's own is more then eight hundred dollars!

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