My husqvarna 136 is killing me- even after carb kit- please help

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clydesdale6

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I could use some help. The saw was bogging down after biting into the wood for about 5 seconds. So...I saw that the fuel filter was broken off of the fuel line. I put in a new line and new filter. The fuel line is clear Tygon LP1200 .080x.140 and the filter is OEM husqvarna.
After that, I couldn't get the damn thing to run for anything. I struggled mightily getting the new line it, but it is in. Since it still ran poorly, I tore the carb down and put a new Walbro kit on it and replaced the needle. I have since put the original needle back in because it will not stay running. It floods. The new fuel line is clear. I can see larger bubbles running through the line as it runs for the the 5-20 seconds that it will stay running. After it dies, it often will not restart. I pull the plug and it is soaked with gas.
I have tried adjusting the L and H. I have them both at about 2 turns right now, but it does not run right at all. If I stab the throttle it bogs and dies. Any thoughts on where to go next with this? Thanks.
 
I have given it a few more tries and I notice that when I remove the spark plug, it is soaked, BUT also has some black silicone like pieces on it. I then let the plug dry, fired it up, which took 5-10 pulls and it only ran for 5-10 seconds. I pulled the plug and it was wet again and another back rubbery silocone like bit was on the plug. Any idea what the heck that is?
I have never pressure tested a carb before, but I likely can with a little coaching. But, what is with the black bits?
 
The fuel line was yellow/orange and this is jet black. I imagine the fuel line would be brittle, right?
 
Factory carb settings are 2 turns out on the H and 1 1/2 on the L. I will say the 136 I rebuilt a while back was rich at these settings especially with the H at 2 out. I can't remember where they ended up but the H was in quite a bit more than 2 turns out and the L was not 1 1/2 open.

The way those manifolds and all seal and the impulse design on those saws they can be notorious for air leaks also.

Make sure you didn't accidentally bend the tab on the needle lever.
 
Factory carb settings are 2 turns out on the H and 1 1/2 on the L. I will say the 136 I rebuilt a while back was rich at these settings especially with the H at 2 out. I can't remember where they ended up but the H was in quite a bit more than 2 turns out and the L was not 1 1/2 open.

The way those manifolds and all seal and the impulse design on those saws they can be notorious for air leaks also.

Make sure you didn't accidentally bend the tab on the needle lever.
 
Thank you. I already tried those settings. Where would the air leaks be coming from? Any idea what the black silicon bits are on the wet spark plug?
How do you suggest I proceed?
 
Thank you. I already tried those settings. Where would the air leaks be coming from? Any idea what the black silicon bits are on the wet spark plug?
How do you suggest I proceed?

What's the history on the saw?

On those saws the green impulse pipe just fits in a hole in the cylinder beside the black rubber piece. Then the plastics manifold has a tit on it that slides into the green impulse pipe and it slides also into the black rubber. Those areas all are prone to air leaks. Then the gasket can leak also.

Could be that your obviously pumping fuel but have an air leak now after removing the carb and the saw wont fire because of it and is soaking your plug.

I however am no expert.
 
I am the original owner. This is the first time the carb has been off the machine in 17 years. It has gotten used lightly every fall. However in the last 2 to 3 years, it is getting more use. Where is this impulse pipe and could it be the source of the black bits that are getting chewed into the cylinder?
Thank you
 
I have tried both of them from 1 1/4 to 1 1/2 and that might have been worse since I could not get it started. It will only run with some throttle work on my part for about 10 seconds and then I usually can't get it restarted until I allow the plug to dry.
Thanks
 
I had a very similar problem with my poulan saw and after rebuild with walbro kit as well as new Tygon fuel lines it ended up being a check valve in the carb. That is why I was seeing small air bubbles in the fuel line. Something to check. You could try a Chinese carb knock off which are usually even cheaper than the rebuild kit. Just as a test then you will know for sure. One thing I have noticed is that its hit or miss. Of the 5 chinese knockoff carbs I bought 2 of them were bad right out of the box. The other 3 have been working flawless and tuned perfectly and easily.
 
I am the original owner. This is the first time the carb has been off the machine in 17 years. It has gotten used lightly every fall. However in the last 2 to 3 years, it is getting more use. Where is this impulse pipe and could it be the source of the black bits that are getting chewed into the cylinder?
Thank you

The impulse pipe on the one of my dads I rebuilt was green. And I replaced it and the new one was green so I doubt that us where the black stiff came from. Wonder if some of the sealant that was used to seal the clamshell cap on the bottom of the engine show how came loose. Not sure on that.

If you pull the recoil cover, if I remember correctly you can get a clear shot of the impulse pipe and rubber piece behind it.
 
See attached picture. Impulse pipe is #4. But air leaks between all those parts are common.
 

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Put new plug in. I had a saw that would run for a few seconds until plug warmed up slightly and then die. Plug would be wet. I thought saw was flooded. Plus it was a brand new saw, so I thought surely it's not the plug. But it was.. Also consider metering lever setting in carb as if it is too high it can make saw run rich.

Air bubbles in fuel line don't make sense with running rich. Air in fuel line should make run lean. Only way I know for air in fuel line is low on gas, hole in fuel line, pickup not getting submerged in take. Maybe hole in primer lines or primer...

Also heard a cautionary tale from someone on here about hooking up fuel line to impulse and impulse up to fuel line and that flooded the saw, but I think that flooded it so bad that it wouldn't run period and I just can't see how you could hook those to the wrong line on most of my saws.
 
Get a cheap Chinese carburetor as a diagnostic aid for it: those Walbro WT carburetors are very hit or miss when it comes to rebuilds. The check valve can wear out/break down (and I don't think a spare exists) and I've had one whose needle kept on getting stuck in its seat after thirty seconds of operations. I tried three different needles, reset metering level I don't know how many times (have you got the gauge for it, right? ;)) but it would still get stuck. The only cure was replacement. I had never seen anything like it before and I hope never to see it again.
 
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