Husqvarna 236 impossibe to tune

[honda4life]

Hello All,

I own a Husqvarna 236 (yes I know baby saw).
Last time, the saw died during cutting. No fuel, that was clear.
In the beginning it just died under heavy load but small pieces was no problem at all.

Okay, tried to clean the air filter but still no luck, dropping a bit of fuel in the carb and the saw run short (so ignition is okay).
Cleaned the carb as good and as complete as possible and the saw was able to "run" again, but it's almost impossible to tune right and the adjustment screws are way too much out to be normal.

Today second attempt and I noticed all the fuel was out the tank (started with full tank before adjustment).
Very strange, but yes the past days there was a lot of fuel smell noticeable in the garden shed.
Filled the tank, an afterwards noticed there was fuel under the carb, so leak?
It is not visible where it is coming from, maybe the fuel hoses did not clamp as well anymore to the carb tubes, I don't know.
Yes I run regular unleaded fuel with low ethanol <5%.
(To my experience the little saws does not produce that much exhaust as bigger saws, and doesn't bother that much, so no not going to change.)

I am familiar with carb adjustments for mopeds / motorcycles so I think I have the right feeling to tune a chainsaw as well.
I think there is some air bypassing the carb, does it sound like that, where to look for the problem?

Hoe does a carb work with twi butterfly valves, what's the point?
Is it for flushing the engine with clean air without fuel?

PS: I don't like the 236 because there's too much screws just in the plastic that will become dull over time.
Recommendations for affordable saws with better built quality for homeowners, is it just the 236 as an entry model?

 

[Mad Professor]

Find fuel leak first. If not carb check the line/hose and filter inside tank (filter is not making it leak but could be clogged). Does the carb have a primer bulb? If so another source of possible leak.

The one diaphragm pumps fuel via a connection to crankcase. The other one meters the fuel and has a needle valve. Make sure your parts are installed correctly on the carb. There may also be a small wire mesh screen where the fuel comes in from the hose. If you have this all correct but still can't adjust things start looking for air leaks.

 

[honda4life]

Thanks,

I have the impression there's quite a lot pressure built inside the fuel tank.
This pressure pushes quite a lot of fuel through the hose if the tank is not vented first, so I really doubt it's clogged (and the primer bulb works also okay).
The primer bulb is separated so a leak would have been visible from the bulb.
There are two hoses, one coming from the fuel tank, the other going to the bulb back to the fuel tank. No visible crankcase, I think it's passed trough the gasket and is not clogged.

 

[ironman_gq]

Start with checking for air leaks on the saw, either between the carb and saw or the crankcase gaskets or seals. Could also be deteriorating fuel lines causing it to starve for fuel on longer cuts but that doesn't explain the new issue with not being able to tune it. I would take the carb apart again and clean it thoroughly again, pay special attention to the small passages for the low and high jets. Make sure the gaskets are good between the carb and engine when putting back together and that the fuel and impulse lines are fully seated.

The leaking gas could be a faulty tank vent or a leaking needle in the carb or again the deteriorated fuel lines.

 

[KYsawman]

If you want another carb to try I several parts ones, PM me and I will send them your way.