Service & Maintenance Question
Got an older Husky 350 that's been running well....escalated
Service & Maintenance Question posted January 30, 2014 by reuven spero
76 Views, 8 Comments
Question:
Got an older Husky 350 that's been running well. Suddenly, in a job, the engine sounds fine but the chain is not turning. a funny, loose metallic sound in the body. opening up, and the "cup" that the clutch sits in spins around freely - I know it didn't used to be like that! Is this a worn out clutch issue? How do I progress with a repair - I don't mind doing it myself.
Answer
Reuven,
You sure do run across some strange problems.
But here goes based on your description: Remove the clutch cover, and bar and chain. Next remove the clutch, drive sprocket, and needle bearing. Inspect all of the parts, It almost sounds like your sprocket has broken free from the drum, I am not exactly sure what kind or Manufacturer of drum sprocket you have but there are different types, and also different ways they are put together. Some of them the gear is welded on to the drum, and others are pressed onto or into the hub of the drum, almost like a crimp or rolled compression fit. Anyhow, If the gear spins free of the drum then the easiest method of repair is to replace it. While you have it apart you should also check the clutch, check the springs, check the outer dimension/ diameter around the shoes, their is an Optimum value but again without knowing the Manufacturer it may be difficult to determine, On My model 455 chainsaw the optimum clutch diameter is 65 mm, and if its less than that the shoes should be replaced, but that could be different on your model 350.
Note: The clutch diameter with shoes has to be at the optimum dimension, so that when the chainsaw reaches clutch speed, the clutch will fully engage. The typical clutch speed is about 3800 RPM's but this will also vary depending on the chainsaw. If the clutch does not fully engage then when under load or heavy cutting the chain may stop in the cut or hesitate cutting even though the engine is at full throttle.
Now, the needle bearing inside the drive sprocket there are different types of these too some are pressed into the hub of the drum, and others are easily removed, also some of the needle bearings are loose needles, and some of them are in a retainer cage and will not come apart, you will find this out when cleaning the needle bearing if it falls apart. The needle bearing is very important also the weakest link of the clutch and drive sprocket assembly, and usually made to be replaced. The bearing has both an inner race and an outer race which is actually the thickness of the needles, when the bearing starts to wear the drive sprocket will start to get sloppy and actually develop a wobble too. I check the fit of the bearing to the crankshaft, and then check the fit of the drive sprocket hub to the outer race of the needle bearing, if everything fits properly there should be little to no movement. I always use Lithium grease but Husqvarna recommends EP-0 grease which is just a little thicker than heavy bar chain oil, so its viscosity is somewhere between an oil and a grease. If I suspect the bearing, or If I am replacing the drive sprocket I always put a new bearing on, they are very reasonably priced usually $4 - 5.00 US. Its real important to periodically Inspect this bearing and make sure all of the needles are in place and that you have a good fit, I have had chainsaws that were missing needles, and the crankshaft was scored and worn down because of a faulty needle bearing. So that reasonably priced repair becomes an expensive if you end up replacing the crankshaft for the cost of a needle bearing or worst yet lack of lubrication. Oh, and dirt gets into this bearing very easily which is another problem, so it needs to be cleaned and lubricated periodically. If I am repeating myself its because it is very important.
I don't know if this answers your question, but I hope it helps.
PS. I am Not a Husqvarna Representative or an Authorized repair Center, Just an experimental chainsaw person.
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You want to see some strange problems, you should see my kids :-) but I doubt if even an experimental chain saw person could help there. But maybe so...
1) this seems like a major messy job i don't mind trying it, but is there a site like ifixit that has pictures and can explain what these things are and what to look out for? I wouldn't know a needle bearing if I found it in my soup.
2) ditto for tearing down a motor (which I know I don't need to do yet, i hope, but still...) I envy you your skill set. Is there something like small motors for dummies or some book like that which can help me through this? ever thought about running a web workshop for this stuff - i'm sure there'd be interest.
3) still working on the 435, but i hope to get to the 350 next week or so. if you don't mind, i'll post pictures of what i find. maybe you can identify the make of clutch/drum/sprocket.
very grateful for your help,
reuven
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Reuven,
Thank you for all the compliments, and too funny about your kids. Lol.
I really don't have any good recomendations on books, I have several books myself but I found most of them are way too basic and after reading the book, you still would not be able to fix anything, and yet others are written far too advanced, and unless you wanted to try calculate the formula's for air flow through the engine, then they would be out of the question too. I like the "Dummy Series" of books because they are written for the lay person, but I don't know of one in that series that does small engines (ie. 2 cycle, chainsaws, etc.). There are alot of U-tube videos, which you can glean some good Info from them, but you need to be very careful of the individuals mechanical ability, I remembered one individual U-tube that was trying to demonstrate how to take a clutch apart, and had the clutch on the bench with needle nose pliers in one hand, and a screwdriver in the other hand and trying to pry the springs apart, after I was done snickering and laughing, I saw a couple of the pictures showed his hands that were all cut up and bruised from scrapes and cuts, and also realized how dangerous what he was trying to do, and show on U-tube. So you need to be very careful what the source is for the Info and besides hurting yourself but further damaging what your trying to take apart. By the way the clutch is very easy, if you know how, and on some cases have the right tools! There are also several Websites that you can join, but some of them are more focused on antique and old engine repairs, but they may answer a few questions on a newer model or specific Manufacturer and Model #.
Please send some pictures, that may help me see what your doing, and I may have some better answers for you of things to check. I have a couple Model 435's which are together and running great, so If I see your pictures I can take mine apart and put them in the same condition as yours and see if it will duplicate the symptoms.
I hope this helps, Oh and I like some of your suggestions but Not sure If I really want to write a book, or put together a series of self-instructional videos. I taught mechanical and electrical technology for a major corporation before I retired, Lol.
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hi karla - had a free evening and decided to knock off the clutch and see what's up.
ok, first of all, the clutch drum had detached from the star shaped sprocket. I assume this was all one piece at one time and so I'll search for a new on ebay. i didn't notice any issues with the needle bearing, but I'll take your advice and replace it anyways. This was not nearly as big a project as I had imagined - a couple of whacks with the hammer and the clutch came free.
as far as the 435T goes - still waiting for the tach to come in. rather than being impatient and trying to do it by ear, I decided to be patient and wait. Shipping will take a week or two.
thanks again, and i'll be in touch.
reuven
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Reuven,
Thank you for the up-date, and yes you will need a new sprocket drum, I always put a little lithium grease on the new bearing too. Also now that you have had the clutch off one time, it does get easier each time, and I would recommend once or twice a year, a real thorough cleaning and lubrication of the needle bearing. If your using the chainsaw every day, then maybe a little more frequent depending on how dirty the clutch gets from use.
I think you will be happy with the tach, and I think its a good idea to tune the T435 with a Tach, that engine really screams and its pretty difficult to tell If your running it beyond specs, fastest speed is not always the best, just get into the RPM range on the High throttle. Oh, also don't forget to get, the idle and clutch speed adjusted first, so that it idles good and a little on the rich side, then do a couple starts both cold and hot and make sure it starts easily in both conditions, and Finally or last get the high speed adjusted correctly, and your done.
If you need any help, just give me a shout!
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hi karla
last week, i finally got the time to reassemble the 350 with the new clutch drum. fine day, went out, started up smooth, cut for about a half hour, throwin chips and finishing up cutting a pile of wood into firebox chunks. everything as sweet as could be - thanks for your help. the 435t still smokes a bit, and tearing down the carb seems like a good idea, as soon as I get the time. thanks again for all your help and support.
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Reuven.
Thanks for the update, and glad everything is working, and that I could help.
Here is my latest project that I am working on today, and its almost finished. I wish I had taken a before picture, it was a real mess, and I bought it through e-bay at a very reasonable price ($ 24.95). Lol.
See attached picture.
PS. Also, I believe the original problem with it was the bar chain oiler stopped working, since I found one of the oil lines plugged with debris, then since the bar was not lubricating, the chainsaw started heating up and resulted in the piston ring getting stuck in the piston groove with lots of carbon. There was no damage to the piston or cylinder which was amazing but a good cleaning, and a new piston ring, and its on its way back together. Oh its a Model 455, I kind of specialize in 455's and T435's, but I really do like the entire Husqvarna line of chainsaws.
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that's beautiful! how did you get it so clean? and that there was no damage to the cylinder or the piston is pretty amazing.
even with the smoking, i'm real happy with the 435T and the 350 is just such a workhorse, and what a great weight to power ratio. one thing that ticks me tho looking through this forum is seeing how many folks have issues with their mufflers falling off the 350 - happens to me too, but I think it is solved at least in the meantime - and then what sounds like Husky reps wither denying that it is a design flaw, or Husky not standing behind their product as they should. I also have a fondness for husky saws, but people will go with better service and responsibility, and husky should know that's the bottom line. That's capitalism, dude! Another company with Stihl their customers :-)
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