Husqvarna 235 Tuning

[Carbine]

I am working on a Husky 235 for a friend, and cannot get this piece of junk to run well to save my hind end.

It probably has 5 hrs on it since new.
There appeared to be case sealant on the inside of the spark screen also, pretty impressive piece of equipment I must say.
Does anyone here have specific experience with this saw, and/or carb recommendations?

I think it's partially just a bad carb, but this guy isn't going to sink a dime in it (I wouldn't either). I'll make it the best it can be and send it back home.

I've read some on these saws, and finding a tune seems to be a common problem. I'm not sure if this saw shares most of its parts with the WT and other Poulans, but seems like some of them have an abnormal amount of turns out on the needle settings. I just tuned a PP4618 earlier this week (or something of the like), and was no issue at all.

I won't even keep it in the garage, fraid whatever it has might be contagious lol

 

[CR888]

Case sealant on the spark screen is a problem as it will restrict exhaust breathing. Have you cleaned the carb out, checked impulse connection, fuel lines etc. When you say it won't tune, what exactly is happening? They are the cheapest saw Husky makes & sells but many get sold and cut plenty of wood. At 5hrs run time this most likely is something pretty simple.

 

[DELETED (Struggle)]

My money is on an air leak where the pan meets the crank seals. Everyone I have ever had with a tune issue has shown an air leak there in the corners.

If it won't tune the very next thing you should do is a vac/pressure test. Otherwise you are wasting your time trying to get it to tune.
Sent from somewhere

 

[Carbine]

Case sealant on the spark screen is a problem as it will restrict exhaust breathing. Have you cleaned the carb out, checked impulse connection, fuel lines etc. When you say it won't tune, what exactly is happening? They are the cheapest saw Husky makes & sells but many get sold and cut plenty of wood. At 5hrs run time this most likely is something pretty simple.

Correct, the spark screen wasn't helping matters.
Saw will start, idle for a couple minutes... I'll cut a couple pieces of wood, I'll set saw back down and saw will stop running.
Restart on high idle takes 3-4 pulls, saw will not restart without it. I'll restart saw, and saw acts like it is loading up (seemingly very rich) at WOT.
This saw does not roam around rpm under no load, it will just not idle. I'll give it more fuel, may idle for a couple minutes.. and it shuts off. Restart, and idle circuit seems to need leaned out, just not holding tune.

 

[Carbine]

My money is on an air leak where the pan meets the crank seals. Everyone I have ever had with a tune issue has shown an air leak there in the corners.

If it won't tune the very next thing you should do is a vac/pressure test. Otherwise you are wasting your time trying to get it to tune.
Sent from somewhere

You may very well be right, although I've been into saws with leaking seals and/or pan seals and they tend to float/ surge. This saw does not exhibit that behavior, but will not hold a tune (mostly at low side idle). I'm on my phone, I'll be more descriptive when I post back tomorrow.

Lines are good, I fixed purge line on primer everything else looked good. I will not be pressure/vac testing this saw but he is more than welcome to if he wants to invest the time.
On the H side, this saw will consistently hold safe rpm, its like the problem is specific to low side circuit.

 

[Carbine]

And thank you for the input fellas.

 

[Adirondackstihl]

Had one last year just like it.
Bad carb
It's a known issue and there is an updated carb avail.
$42

 

[panteliss]

Husqvarna 235, 236, 240 have problems with theirs carbs , vents systems , and bearings

 

[Mastermind]

I was gonna say......bad carby. Y'all beat me too it.

 

[panteliss]

Personally i have see over of 50 -60 new saws that do the same , no leaks no nothing and they dont hold idle , bogging , etc i speak with the most dealers here and they say the same
and of course the husqvarna scrapes its balls .................. as always

 

[CR888]

Is there a cheap AM carb available on EBay? Them saws are only like $249-$299 here, they must almost be free in the US.

 

[Carbine]

I think they are around a couple hundred bucks here.. I havent seen what was on it yet, been a rain filled weekend. I agree, I would give an AM carb a try in a second on something like this. I've had good experiences with them myself, and more often than not I think they are probably made right along side the OEM counterparts.

 

[Mastermind]

Finding a source for OEM carb parts is the first battle, then figuring out what to replace is next. I'm betting it has a leaking check valve in the main nozzle. Sometimes a soak in carb cleaner will fix that. Other times it will not. The "valve" is nothing more than a flat piece of the same material the pump diaphragm is made from, and they get hard and out of shape from ethonal fuel. Can you trouble shoot the carb?

 

[jk14]

I had a 445 that wouldn't idle right out of the box. It didn't respond to any carb. adjustment whatsoever. That POS. went back and I got an ms251.

 

[Carbine]

Finding a source for OEM carb parts is the first battle, then figuring out what to replace is next. I'm betting it has a leaking check valve in the main nozzle. Sometimes a soak in carb cleaner will fix that. Other times it will not. The "valve" is nothing more than a flat piece of the same material the pump diaphragm is made from, and they get hard and out of shape from ethonal fuel. Can you trouble shoot the carb?

Rain just let up, I'll report back with my findings. I've had pretty good luck wrastlin' with carbs, aside from a few duds (which replacements have fixed).

 

[Carbine]

I gave it another whirl before I pulled carb, and got it to tune out. It idled for 10-15 minutes before running out of fuel.
I won't say that this is a "bad" carb per se, but I don't think the mechanics of the carb itself are worth a hoot.

Saw started up easy, and I held half throttle (essentially leaning saw out momentarily), and let it go back to idle. Saw stalled after a few seconds, so I richened L side about a 32nd of a turn (I am not exaggerating, I have never seen a carb this finicky). Started back up, gave it a half throttle blip and let it go back to idle, which it continued to run. I brought back to WOT (I leaned out H speed about 32nd of turn from where I was at when I made L speed adjustment), and again- let saw go back to idle. It stalled, seemingly rich at idle. I adjusted H side again and let it be. Sometimes coming off of WOT, it may stall when returning to idle, sometimes not. When it stalls, it seems like the residual fuel from WOT is bringing idle down just enough to stall.

For this saw to be in the comfort zone at WOT, you will not find a consistent idle speed IMO. I think I could probably lean out H speed some more, but I don't think it would really help. Going leaner on L speed makes coming up to WOT sluggish, and you cannot get saw to idle (even trying to compensate with idle adjustment).

Sorry for all this babble, if this was my saw I would experiment with carb in the name of science a bit... But this is a quick tune and return and we are both satisfied with the results. To be continued...

 

[Carbine]

OEM Replacement (Zama)

http://www.ebay.com/itm/Zama-C1T-W3...242129?hash=item4d30904191:g:7W4AAOSwBahVKFte

AM Replacement

http://www.ebay.com/itm/Carburetor-...718452?hash=item19f3d0a074:g:8E0AAOSwxH1UJTaP

 

[Adirondackstihl]

It'll never be "right" until the carb is replaced.
Trust me.
Been there
Once the carb is replaced, remove the limiters and let it rip.
Not a great saw to start with, but not bad either

 

[Carbine]

It'll never be "right" until the carb is replaced.
Trust me.
Been there
Once the carb is replaced, remove the limiters and let it rip.
Not a great saw to start with, but not bad either

I'm not so sure yet, but you may be right. This is a 2011 IIRC, it does not have limiters... but does have the splined needles that Poulan has been using for a while. But yes, if it was mine, I would buy that 20 dollar AM carb and call it a day. If it has another hiccup, I'll talk him into the AM carb.
He is a buddy of mine, and I told him... You make good frikkin' money and you can spend more that 200 bucks on a chainsaw? Cheap arse I called him lol.

 

[Carbine]

It's not that I don't like fiddling with carbs, but when I see a cheap AM replacement... I get impatient with what I have. A while back, my BIL found a deal for me on a compact tractor. He needed a saw at the time, and as a gift to say thanks, I bought a Husky 55 that needed rebuilt (I put a new piston, rings and cylinder on it). I could get the saw to idle, but the thing would go lean at WOT no matter where its tune was at. Had it on and off the saw, quite a few times, and the carb itself apart more than I care to remember. The thing was spotless too. I got tired of scratching my head and bought an AM replacement for less than 20 bucks, and never had another issue.