Stihl BR 380 Blower Cuts Out

[gdubyacobb]

I have a Stihl BR380 that has started cutting out like it is starved for fuel.
I have pulled and drained the tank, replaced the fuel pickup (filter).
I pulled the carburetor, removed the bowl and cleaned the whole thing.
I have cleaned the Fuel Tank Vent as much as possible. (this is where I am thinking the issue still is)
It will fire right up and run, but when I pick it up to put it on my back it will sputter and sometimes quit. If I get it onto my back it runs, then starts to sputter until I shake to jostle it and then it will run until this process repeats. Its like I have to dance with it to keep it running.
If I get it running while it is sitting on the workbench it runs fine until I begin to shake and tilt the unit. It then sputters and dies. Unless I shake it again in time enough to catch, then it runs until it all happens again.
So Tank Vent or maybe a check valve in the carb?
The nearest Stihl shop is over an hour away, so I would really like to fix this myself.
Thanks in advance for any help you can offer.

 

[lazer50]

Inspected fuel line from carb to tank for cracks? Mufflers will plug up over time also

 

[Heel2toe]

Maybe the diaphragm in the carb has gone bad? If its the vent on the gas cap then you can eliminate that very easily. Start the thing up with the cap off and see if the problem goes away.

Have you tried adjusting the carb? Sounds like maybe you need to turn out the high speed a little if its bogging...

 

[buba]

I have a Sthil BR that exhibited similar behavior, but mostly when I rev'd the engine as opposed to just moving it. Turned out to be a fuel supply line E10 gas failure problem (tank to carb). The fuel supply line had no cracks but was very soft and appeared to be collapsing in on its self when under pressure when compared to the replace part. Been using E0 gas since then (5 yrs) with no repeat issues.

I also replaced a burnt valve at the same time but I think the fuel line was the main problem.

 

[Heel2toe]

Yeah I mean it certainly sounds like its starving of fuel so the question is why? There are a few reasons it might not be seeing fuel. The line is suspect as well, I guess I assumed he replaced the line when he did the fuel filter. But good point it could certainly be that ethanol has a tendency to shrink seals and rubber parts so fuel line is no different.

 

[gdubyacobb]

I checked the fuel line for obstruction and cracks, but did not replace it as it was replaced under a year ago.
When I took the carb apart everything looked very clean and the diaphragm and gasket seemed pliable.
I will try a new fuel line.
Do I have to go with a Stihl line? Is there any reason I cant just use fuel line? Nearest Stihl dealer is over an hour away.

 

[Heel2toe]

No you dont need Stihl line. Do you have a small engine repair shop nearby? They should have fuel line in various sizes by like Stens or something along those lines. The color might not match so as long as that doesnt bother you then it'll work fine.

So have you tried adjusting the carb? My money is on that at this point.

 

[wvhillbillie]

Inspected fuel line from carb to tank for cracks? Mufflers will plug up over time also

I've had an issue with a clogged muffler before.

 

[Davefr]

Check the fuel line for cracks/blockage/softness and then remove the carb. Take the fuel inlet plate off the carb. That's the plate that has the fuel line fitting close by.

Now look to find the little screen where the fuel goes into the main body. Does it look like this? If so, it's crappy ethanol gas that's turned to slime.

Clean that **** off the screen and it'll probably be just fine. Don't adjust the carb. until you diagnose the problem. That'll just make things worse.

There's a tiny screen under this layer of ****. I missed it the first time.

Shaking the blower probably frees up that **** for a few seconds but it get's sucked right back against the screen due to vacuum from the engine trying to **** gas thru.

This is what the screen should look like:

 

[B_Bimmer]

I've had an issue with a clogged muffler before.

I third this.

 

[gdocktor3]

I've also heard of clogged mufflers before on those. Alternatively, I had a weedwacker do that. I screwed around with all sorts of nonsense trying to clean it and adjust things, spark plugs, etc, but in the end I bought a cheapo replacement carb off ebay for like $13 or something. It came with new gaskets, fuel lines and filters and it has worked flawlessly ever since.

 

[Bluejoe]

That is a fine screen in carb. That's debris inside rolling around. You can clean out but be careful. That's included in rebuild kit. That junk is in carb so you have to take apart and flush several times before you get it all out. Also diaphragm gets hard so use WD 40 on it if you just clean up carb and not do a full rebuild. Also watch where all parts go in sequence. There different. Most of times you should soak in carb/parts cleaner overnight.

 

[4Kings]

Also watch where all parts go in sequence. There different. Most of times you should soak in carb/parts cleaner overnight.

If you choose to rebuild the carb, just be aware that most of the kits you get today cover several models, meaning you'll have more parts than you need for your particular carb. Like Bluejoe said, just lay everything out and take pics