# Echo backpack blower stalls at full throttle after one hour



## Michael S

Hi there,

I have a 5 year old Echo backpack blower (can't recall model #) and it runs well for about an hour. After an hour or so it starts to stall at wide open throttle. If I don't back off of the throttle it'll die. If I'm quick I can back off of the throttle to idle and work it up to wide open throttle again. Sometimes it takes a couple of quick transitions from idle to full throttle, idle, full throttle, idle, full throttle, etc. After a few of these it will run wide open, but it quickly stalls again after 10 seconds or so. If I let it sit for a long time so that it cools down, etc. it's back to running normally. 

I've tried topping off the fuel in case it was a low tank and I was sloshing about. I tried moving the choke from the run position to a little more towards cold start. The fuel is new, properly mixed, with Sta-Bil in it. Last year it did the same and I checked the plug at that time and it looked fine. The air filter appears to be clean. I have not tried any gas treatment like Seafoam yet.

I called a repair shop and they suggested the carb may need replaced. That's OK if it does, but I don't want to replace it willy nilly if that's not the problem. Given that it has to run at full throttle before the problem occurs I have doubts that a repair shop will do that to reproduce the issue before replacing parts.

Any help is appreciated.

Thanks,
Michael


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## 30yearTech

It could be the carburetor, may have a leaking check valve that sticks when it gets warm. The more likely culprit is an air leak that develops when the engine is hot. This could be a crankcase seal, or a leak in the cylinder head gasket or somewhere in the intake between the carburetor and cylinder.

If the crankshaft seals are leaking there should be some oily residue in the area around the flywheel or starter. You can check for air leaks around the intake or cylinder base gasket with some brake cleaner spray. With the engine running, spray some cleaner around the suspected areas and listen for a change in the engine running tempo, this will generally indicate an air leak.

Best of Luck....:thumbsup:


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## Michael S

Thanks. I won't be needing the blower again until Saturday (weather depending) so I'll check it then.

If it's a check valve is this something that a fuel cleaner could free or not at all? I guess for good measure it wouldn't hurt to add a little and toss the rest in my truck.

Brake cleaner: Do you mean spray the liquid directly onto the blower at those locations? I just looked at it and it appears that I could remove the protective shroud and still use it just fine making it easier to get to those locations once it starts acting up. I assume that you mean do this after the problem has presented itself. Would I be able to just do this at idle? Also, if it runs differently are there any additional steps to isolate which seal/gasket?

Last, are those gaskets/seals difficult to replace with your average set of hand tools? I'm somewhat mechanically inclined with a full assortment of hand tools, but nothing specialized. The various components appear to be easily accessible.

Thanks, 
Michael


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## Michael S

> are there any additional steps to isolate which seal/gasket


I mean in addition to looking for oily residue where you've indicated. I haven't popped the shroud off yet to take a good look.


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## 30yearTech

Front seal is not hard to do, back side seal requires quite a bit of diss-assembly to get at it. Cylinder base gasket is also a lot of work. 

Yes you would spray the liquid at the suspect locations while the engine is running, you don't really have to wait until it's real hot, any leak will likely show up, but you can try it when it's hot as well, just be careful spraying around a hot muffler.


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## Michael S

It has been a while since I started the thread, but I took it to a small engine repair guy. He cleaned the carb and drained any debris from the tank. He also said that the coil was acting up once it got hot and he had an old one lying around that he put in and those seemed to fix it. I ran it this weekend for about 2 hours and it was running good again.


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## 30yearTech

A faulty coil does not cause the issues you described. If they fail when the unit gets hot, then the engine stops and you can't get it started again as it looses spark. Once the coil cools down and spark is restored it will again start and run. Your coil may have been failing, but it wasn't causing the symptoms you described. That was likely the carburetor, glad it's going again good for you!! :thumbsup:


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