My nemesis, that leaf blower again...

[trader_4]

So, my leaf blower that has been a source of much trouble in the past just started in again. Last two times it was that the piston ring had carbonized and stuck. This time, IDK haven't started on it yet. Fortunately it worked for what needed to be done, so I have a week or so to fix it or get a new one.

Here is what happened this time. I've been using it occasionally, more recently I used it a week ago and it ran perfectly. At that time I was filling it with mixed fuel from a 1 gal jug. Yesterday it started up ran fine, until it was running out of gas, or at least I thought it was. The gas was low, but after the rest of what happened, I thought back and I think it may not have been as low as it normally is when it starts to starve for gas. So I filled it up again, this time what was left in the jug was the very end of that volume, it basically was enough to just fill it. Started right up, ran for a couple of minutes, then started having problems, unable to run at full speed, struggling.

So I immediately wondered if that last gas had something to do with it. I mixed up a fresh tank, poured out what was in the blower and filled it with the new mix. Started right up and ran perfectly fine again. For about 15 mins that is. Then suddenly started crapping out again. I did notice that if I tipped the front end down, it would pick up and run better again. But that only lasted for a couple mins, then it went out.

My first suspicion is that something could be wrong with the fuel lines, like maybe broken off inside the tank? When I pump the bulb I can see fuel flowing, which seems to discount that, you'd think it would be sucking air. So, IDK, have to start investigating. Any guesses?

[Shadow]

I know next to nothing about engines. If it was a heart, it could be one of the arteries' walls had "come loose" and was acting like a valve. IOW, with the gas flowing fast a rusted/rotten section folds down and blocks the fuel. Next I'd look at what regulates how much blood (fuel) gets there. In the case of an engine, the carburetor(leaky float) or injector. It could be the lungs (blocked/soaked/wet) air filter too. You didn't describe how it works. Sorry, that's the best I've got. []'s

[Clare Snyder]

Just ran across that same problem with a 15 year old Stihl. It was the fuel line where it goes into the tank. It has an "accordian" section and it was cracked it the root of the bellows. Was a bit hard starting

- ran for about 3 minutes then leaned out and died.

It wasn't cheap but a lot less than a new blower.

[trader_4]

Yes, that's one of my suspicions too. But I looked for air bubbles in the fuel lines when this was happening and there were none. And yesterday before diagnosing, I decided to try starting it again. It started right up. Some smoke was coming out of the exhaust for about two mins, I presume that was because it had been flooded from the failed starting attempts a few days ago. After that it ran just about perfect for an hour. A couple times it seemed to just start to hesitate a bit, but quickly recovered. I guess I'll just keep using it, try to get through the next 6 weeks of leaf blowing, that I hate so much. Blew them away yesterday, today hard to tell, so many more have dropped.

I wonder if a fouled piston ring could cause the symptoms? That was the problem the last two times. But then it just would not start. Wonder if it's possible that when it heats up, sometimes the piston ring gets stuck, it loses compression? IDK

[FromTheRafters]

Another SWAG IIUC could be the ignition coil is cracked and opening when the temperature expands it enough.

[Roger Blake]

The problem is liberals. Eradicate them and and most problems will vanish. Economic destruction unleashed by the incoming regime will only hasten the coming of that happy day when the freight trains will be carrying Leftists to their final destination.

[trader_4]

That's a possibility too. Here is the latest. I used it again for about 20 mins the other day. It started right up, ran almost perfectly, an occasional little hiccup, but full power. Then it just started struggling, barely able to run at half power.

Today I started working on it. First thing I discovered, the intake fuel line had broken off right at the filter. So of course you think it's possible the fuel line might have floated around, but when it was having trouble I looked at the fuel lines and no air bubbles. So it wasn't that, but it has been sucking up gas without a filter and the trouble started when I refilled it with the last of the mixed gas that was in the gallon tank. So, figured maybe some debris got in the carb. Took the carb apart, it looks fine, no gunk, no debris, no corrosion. Blew it out with air.

I had also noticed that when running it looked like som fuel might have been coming out between the carb and intake. There is a special shaped o-ring like gasket there. Can't order a new one. So when I went to put it back together again, I put some RTV on that area. Put it back together, it started right up. Ran for 15 mins perfectly, then same thing, started bogging down, then quit.

I'm thinking this could be that freaking piston ring again. Twice it got fouled and stuck, so it lost compression. I'm thinking that when it gets hot enough, maybe it starts to stick? That's next on my list. Unfortunately that requires more disassembly than the carb :(

[trader_4]

Just tried it again. Started right up, ran perfectly for 30 mins. Got what I needed done, For now, I;ll just keep trying. Maybe it's that piston ring sticking sometime and maybe it got better? I learned one thing from this that I should have learned last time. When the mixed gas is down to just enough for one fill, I'm going to chuck it. Not only is it the bottom of the can, but it's also the oldest. Water would tend to be on the bottom too. It's a problem because unless you want to measure small amounts of gas and oil, you have to mix a gallon at a time. That means it winds up sitting, often for 6 months or more. On the other hand, for the first ten years of usage, the blower had no problems. String trimmer doesn't seem to either.

[trader_4]

So I used it again the other day, ran for about 30 mins this time, then started struggling again. I just ordered a new carb. When I had it apart, I noticed that the diaphragm that serves as the fuel pump appeared to be stretched. IDK how tight or loose it's supposed to be, but I think new ones are tighter, like a drum. Wonder if that's what's wrong? A new carb was only $10, so I'm giving it a shot. Even if it's not and I get it straightened out, having a spare is handy. But if it is the diaphragm thing, I can't explain why it works for 30 mins, then craps out. At least it works long enough to mostly get what I need done, so far.