Husqvarna 350 carb adjustment

[larrypac]

I have an old Husqvarna 350, probably the first version of it around 1998-99. It has had some scoring on the piston for the last 8 years or so but still gets the job done. This morning I was cutting up some 6"-8" birch and the rpm was not dropping down quickly when i let off the trigger and then it stopped idling properly. I messed with the carb adjustments some but the screws have plastic limiters which basically only allow about 3/4 turn on each screw and I could not detect much difference with the L screw all the way in either direction. I also took the filter and diaphram from a saw that I found at the dump, and it will run and run great at the top end but still does not return quickly to idle and more often than not, stalls. Any advice would be greatly appreciated. BTW, while I was writing this post a new chain arrived. perfect timing. larry

 

[ChillyB]

The nubs on the caps can be whittled away with sharp knife. The screw slots on mine were worn so I broke off the caps. Underneath are very small diameter shafts with screw slots. I put fuel tubing over them to form cups to guide my small screwdriver

 

[larrypac]

Is the correct setting likely to be outside the stops? Also, as I think about it, it happened pretty suddenly so is it liable to just be an adjustment, or should I be looking at something else?

 

[grizz55chev]

Is the correct setting likely to be outside the stops? Also, as I think about it, it happened pretty suddenly so is it liable to just be an adjustment, or should I be looking at something else?

It's probably not going to adjust properly if there is scoring, in my past experience. You will fight it for a while but never get it to where it's happy. 350 is my go to firewood saw, and they are pretty simple and cheap to fix, so maybe do a teardown and save it before it's damaged to badly, if you plan on keeping it.

 

[Woodslasher]

Does it have the updated boot with the metal clamp or the old style one with the plastic clamp?

 

[larrypac]

It has the plastic clamp. I have seen references to the newer metal clamp. What was the issue with the plastic one?

 

[ChillyB]

Here's my new guy recommendation. My early 350 ran good but had the plastic clamp. I was intimidated to pull the jug just for the boot clamp. But I did it anyhow and it wasnt hard. Just focus on a clean workspace, don't get trash in your rod bearings, and rebuild your top end before it becomes ruined. Having now demystified chainsaw engines I would do another in a heartbeat. A 350 is too nice a little saw to run to ruination.

Detail-clean your saw. Take off tank/handle, clean some more. Take off the muffler and clean some more. Remove carb and clean some more. THEN pull the cylinder, adapter base, crank assembly. Put crank assembly in a zip lock bag. Clean the saw until you can eat off it. Remove any aluminum transfer from cylinder. If it comes out OK THEN put it together with a new piston, ring, no base gasket, new fuel line, rebuild carb, update the intake clamp (check boot for any cracks or holes).

If cylinder is toast then look up 346XP upgrade. Or just do that anyhow if you want an angry little saw. My cylinder and piston were nice so I didn't do that.

 

[ChillyB]

I hesitate to link this because I'm by far not an expert. So take it with that in mind. This is the account of a new guy who managed to do it and has no regrets. Just do it and stop procrasturbating.
https://www.arboristsite.com/threads/husqvarna-350-rebuild.359835/

 

[Woodslasher]

The problem with the plastic clamp is that it will allow the saw to leak air into the intake, causing a lean condition and scoring the saw. the updated style won't be as prone to leaking (I won't say they don't leak because everything has the potential to leak).

 

[larrypac]

Having read the 5 page long thread on rebuilding the 350, If I decide to do a rebuild, rather than buying a new 435 for $320 from a local equipment dealer (not a big box store), Where would everyone recommend I buy the parts? And how much will I expect to spend on this project?

 

[skeet88]

Cant offer suggestions for parts but can’t say from experience the plastic clamp will fail and cause a horrible death .Good Luck on the rebuild if you decide to go that way.

 

[J D]

From your description & given it happened fairly suddenly, I'm picking either something is mechanically preventing the throttle shutting promptly (ie crud in the spring, a wood chip in the wrong place, bent or displaced linkage, etc) or you have a lean running issue... in that case I'd start by checking the air/fuel filters, then lines, then clean carb out & if nothing has been found do a pressure/vac test on it

 

[ru55wood5]

Having read the 5 page long thread on rebuilding the 350, If I decide to do a rebuild, rather than buying a new 435 for $320 from a local equipment dealer (not a big box store), Where would everyone recommend I buy the parts? And how much will I expect to spend on this project?

first, let me state that this is the view of one really dumb person: me. but i have an opinion and the internet says that means i am qualified to speak...

i have the 435 and my neighbor has a 350 that i have used a few times. personally, were it my choice, i would rebuild the 350 before i purchased a 435. they are just in different leagues in terms of power and build. more specifically, my 435, which i did buy from a box store, lacks power for a 40cc saw and has a single bar nut that I hate. the single bar nut issue has been debated before, but from my vantage point: (1) you put all the side plate pressure on a single point and rely on it to hold tension for the bar holding a chain spinning at high RPM (Husky says top end is 9000); (2) if you overtighten it, you are slowing down your chain and if you don't overtighten it, the single nut spins off due to vibration and you tear up the drive links and chain catcher. i have spent a few nights sanding down the drive links so that they sit down in the groove again; (3) if you move up in bar length, which i did from 16 to 20 in (the max), you are really asking a lot of the single nut. Let's assume that my incompetence as a professional homeowner exceeds the allowed assumed incompetence of most weekend warriors buying their chainsaws from box stores, in my experience i have torn up that chain saw and chains more, and lost more nuts, than i have with my Husky 372 or Stihl 066. i finally put on a ny-lock nut to keep the side where i wanted it.

on the other side, i would invest in the muffler support for that 350 if you have not done so already. my neighbors muffler fell off and a bolt stripped because the 350 shook the steel bolts in the aluminum threads so much, it eventually wallowed out. you can but the muffler support on Ebay for $7 plus shipping; it ties into your dogs so it all sits as one unit. my neighbor did it and it is much more solid.

again, i am not a professional, i am the guy you give things to in order to see how idiot-proof something is and i tend to find every possible way to accidentally break something. my personal experience is that the 435 is a dud, and my vote is that you rebuild the 350.

Russ

 

[ChillyB]

Had a used 435. Rebuilt my 350. Sold the 435 for $20 less than I paid. I see no reason to own a 435 if you have a 350.

I ordered my OEM stuff from ereplacementparts.com. But I didn’t need a piston or cylinder (likely no longer available).

 

[BrettS]

Where would everyone recommend I buy the parts?

Don't ask about chainsaw parts on here, you'll have all the OEM anoraks out in force

 

[Chevboy0167]

Best clamp for this mounting style ever! I will report back in morning with part number.

 

[BrettS]

Best clamp for this mounting style ever! I will report back in morning with part number.

View attachment 996859

505283301

 

[larrypac]

So, I cleaned the carb and installed new gaskets/diaphragms, and got it running OK. It is still very slow to return to idle, not from anything to do with the linkage as far as I can tell. I'm now thinking of putting some money into it. Fuel lines and metal clamp for intake port for starters. I have a cylinder from another 350 that looks good and wondering how to go about matching a piston to that cylinder. Is the diameter the only critical dimension or are some pistons longer than others. Unfortunately, the other cylinder does not have compression release. I've read here about eliminating the base gasket. Is there a reason for this? I'm not looking to make this a super powerful saw, just to get it working reasonably well. I'm 73 and if I can use it for 2 hours a day, I consider myself lucky.

 

[J D]

Removing the base gasket reduces squish. Ideally you want about 0.020" between the piston & the top of the cylinder. OEM can be twice that so deleting the gasket gets you closer. It's something you need to measure before making changes or things could end badly.
The compression release isn't really needed on these, a lot of people just plug em anyway

 

[larrypac]

Since I don't care about having the toughest saw on the block, I can't see any advantage to deleting the gasket, and apparently there are potential disadvantages.