Husky 435 X-Torq Compression question, hot starting issue

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Carbon is pretty easy to clean up, plastic scraper, Scotch-Brite even a piece of wood. Break parts cleaner is also your friend.

You won't really know what you have until you pull things apart. Sometimes all you need to do is clean things up and put a new ring on the piston. Let's wait till you have a better look at things.
It rained all day down here so I decided to go ahead and tear into the saw. I'll post a few pics that I took of the piston/cylinder/ring. I found some light scoring on the ring/piston next to the exhaust port, but other than that it was mostly carbon/discoloration. I went ahead and started cleaning the top of the piston with brake parts cleaner and a green scouring pad. I noticed it was leaving a few light scratches in the top of the piston. so I decided to stop, would it be ok to continue cleaning the piston/cylinder with that? I couldn't feel any scratches on the inside of the cylinder but there is some carbon buildup.
 
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I did not remove the caps for the side vents (i'm not sure what they are called). It looks like they have been sealed some some kind of gasket maker. Should I remove those and reseal if the top end can be reused?
 

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If either of you need parts I have a 435 carcass in the barn.

I'm wondering with all of that gunk if the ring isn't stuck.
Surprisingly the ring was not stuck when I removed the cylinder. I did manage to break it while getting it of of the piston though.
 
Don't worry about using the cleaning pad it won't hurt anything. I usually maroon colored pads, I believe they're a bit finer. Clean the sides of the piston, and the ring grove the best you can. Looks like a lot of Blowby, so I think we found the issue. Clean the cylinder up with some 320, and but in a new ring. Good idea to do a vac test after you get it back together, if it's air tight you should be good to go.
 
Don't worry about using the cleaning pad it won't hurt anything. I usually maroon colored pads, I believe they're a bit finer. Clean the sides of the piston, and the ring grove the best you can. Looks like a lot of Blowby, so I think we found the issue. Clean the cylinder up with some 320, and but in a new ring. Good idea to do a vac test after you get it back together, if it's air tight you should be good to go.
I appreciate the advice, i'll work on getting everything cleaned up tomorrow. I have a couple of questions if you don't mind. Would it be a good idea to apply some sealer to the crank case/top end mating surface, in addition to the two rubber seals that are already there? I noticed they were frayed a bit on the edges when I removed them. Do i need to worry about removing the covers from the side ports on the top end, and re-sealing those? Lastly, do you have any tips for sanding the cylinder? This is my first time doing it and i'm a little nervous about screwing it up. Thanks again
 

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Leave the transfer covers on, no need to take them off unless they leak when you do a vac test.

I would replace those gaskets, and I would likely use some proper sealant on the cylinder base and some on the seals. Yamabond, Motoseal, Dirko will all work just fine, regular silicone gasket will not work. Make sure the surfaces are very clean, brake parts cleaner as your friend.

This video should give you an idea how to go about cleaning it up.

 
Leave the transfer covers on, no need to take them off unless they leak when you do a vac test.

I would replace those gaskets, and I would likely use some proper sealant on the cylinder base and some on the seals. Yamabond, Motoseal, Dirko will all work just fine, regular silicone gasket will not work. Make sure the surfaces are very clean, brake parts cleaner as your friend.

This video should give you an idea how to go about cleaning it up.


Thank you! That video game me a much better idea of how to go about this. I started cleaning up everything today. So far the piston is looking pretty good with the exception of the ring seat. I am having a difficult time getting that clean with the abrasive pad, even with liberal use of brake parts cleaner. I considered taking a Dremel and a brass wheel to it, but I wasn't sure if that was a good idea or not. If you happen to have a better way to go about that, i'm all ears.
 
Thank you! That video game me a much better idea of how to go about this. I started cleaning up everything today. So far the piston is looking pretty good with the exception of the ring seat. I am having a difficult time getting that clean with the abrasive pad, even with liberal use of brake parts cleaner. I considered taking a Dremel and a brass wheel to it, but I wasn't sure if that was a good idea or not. If you happen to have a better way to go about that, i'm all ears.
Thin piece of plastic or wood can help clean the groove out. As long as there really isn't any thick buildup just clean it out with some brake parts cleaner. You don't want to use any power tools to clean out the grove.
 
Just got my 435 torn apart and laid out on the healing bench. The piston and cylinder are perfect. 2 of the 4 main bolts that secure the power head to the pan are missing. Not sure how they fell out, but they're gone. Both of the crank seals are damaged and the PTO side main bearing is shot. Judging from the amount of fine dust everywhere inside this saw, I'd say a 200 pound gorilla really leaned on it with a dull chain.

I need to scrounge some good main bearings, crank seals and a piston ring just to be safe.
 
Just got my 435 torn apart and laid out on the healing bench. The piston and cylinder are perfect. 2 of the 4 main bolts that secure the power head to the pan are missing. Not sure how they fell out, but they're gone. Both of the crank seals are damaged and the PTO side main bearing is shot. Judging from the amount of fine dust everywhere inside this saw, I'd say a 200 pound gorilla really leaned on it with a dull chain.

I need to scrounge some good main bearings, crank seals and a piston ring just to be safe.
Yeah man, wouldn't surprise me if the gorilla was larger than that, because when I removed the bolts from mine they were in there pretty damn tight lol. If you haven't checked the oil pump you may want to do that as well. I decided to take mine apart today for cleaning and discovered that the little plastic gear was completely toasted. I'm guessing it's a common failure on these considering how cheaply made they are. At least your piston and cylinder are salvageable, that's good news.
 
I have been busy the past few weeks, but I figured I would stop by and give this thread some closure. I got everything cleaned up and put back together but the saw failed the pressure test. I had a leak around the clutch side seal. So I ordered a new set of seals, after I installed them the saw passed the pressure test. I got everything put back together and the saw runs great. I haven't really had a chance to work it hard yet, but it seems to have a lot more power. Hopefully the hot starting issue is fixed as well. Thanks for all of the help guys.
 
I purchased a 435 NIB when they first came out. Was really hoping Husqvarna was doing something good with the little stratto saw. Mine ran great and excellent power for the CC's. From day one it was a little "boggy" when you hit the throttle but I got used to it. Just figured that's part of the stratto thing.

Now the bad news. The saw had all sorts of hot-soak issues in the summer months and nearly IMPOSSIBLE to re-start if you shut it down to re-fuel on a hot day. I went thru EVERYTHING and found no issues anyplace. It did fine in the Winter months but the problems persisted anytime I tried to use it in warmer weather. I didn't have much faith in it so I sent it down the road.......Cliff
 
I purchased a 435 NIB when they first came out. Was really hoping Husqvarna was doing something good with the little stratto saw. Mine ran great and excellent power for the CC's. From day one it was a little "boggy" when you hit the throttle but I got used to it. Just figured that's part of the stratto thing.

Now the bad news. The saw had all sorts of hot-soak issues in the summer months and nearly IMPOSSIBLE to re-start if you shut it down to re-fuel on a hot day. I went thru EVERYTHING and found no issues anyplace. It did fine in the Winter months but the problems persisted anytime I tried to use it in warmer weather. I didn't have much faith in it so I sent it down the road.......Cliff
I was having the exact same issue with mine. If it ever sat for a minute or two while hot, you could forget re-starting it until it cooled all the way back down. It seemed to be worse in the summer. I replaced damn near every part on the thing trying to solve the issue. I didn't want to give up because i'm stubborn, and I loved how lightweight the saw was for limbing and light cutting. I suppose I will have to wait and see how it acts this summer after the rebuild before I will know if it fully solved that issue or not. Now that I read what you said i'm beginning to think it's just the nature of the saw and nothing can be done. I already ran through one starter pulley, they are cheaply made anyway, the hot start issue certainly doesn't help matters, that's for damn sure.
 
Just got my 435 torn apart and laid out on the healing bench. The piston and cylinder are perfect. 2 of the 4 main bolts that secure the power head to the pan are missing. Not sure how they fell out, but they're gone. Both of the crank seals are damaged and the PTO side main bearing is shot. Judging from the amount of fine dust everywhere inside this saw, I'd say a 200 pound gorilla really leaned on it with a dull chain.

I need to scrounge some good main bearings, crank seals and a piston ring just to be safe.
Did your rebuild end up working out alright?
 
I ended up sending it to my brother (smokey7) here on this site. I got in over my head with this 435 and it was more than simply replacing the piston and cylinder. Smokey7 has the tools and experience since he lives and breathes 2 cycle stuff.
 

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