Chainsaw stalls when turned sideways

[mpc855]

I have a Husqvarna 345 that stalls whenever I turn it bar side down and give it gas.

It starts fine and seems to idle fine.

If I turn it bar side up and give it gas, it runs great. Useless for most of my cutting... but runs great in that position.

When I give it gas in the normal position, it doesn't always run quite right, revving up and down.

When I turn it bar side down, it makes a "putting" noise when I give it gas, like it's running out of gas, and will eventually die if I hold in the throttle that position for more than a second or two.

After turning it bar-side down and getting the "putting" (but not letting it die), if I then turn it back to bar-side up and throttle it, it putts for a couple pulls of the throttle, and then suddenly seems to kick in and then runs fine. It continues to run fine as long as I hold it in this position.

I've tried a number of things: putting Seafoam in the tank, adjusting high/low/idle screws, replacing fuel filter, replacing spark plug, removing the fuel line and checking it for cracks, and moving the (weighted) fuel filter around in the tank to try to get it into a different position. None of these things have solved the problem.

I'm not 100% sure that the fuel line doesn't have some hairline crack in it that my eyes can't see, but I tried blowing and sucking through it with my thumb over the end and it seems tight, and the problem persists regardless of whether the tank is almost empty or completely full, so it makes me think it's not the fuel line.

I searched Google and one thing that someone suggested for a similar problem was "a leaking seal". The person didn't really go into details about how to check or fix a leaking seal though, and I don't that much about engines, so I don't know what to do there.

Any ideas?

Thanks,
Mike

 

[smilin possum]

Could be a fuel line problem BUT it sounds like you may have a seal going or gone. Most of the time if it wont run in a side ways angle it's lots of times the seals and bearings. Do a vaccum test to check.

 

[HiOctane]

Try opening L screw ,let say 1/8 @ 1/4 more.You should feel a difference.If not,then you need to have a pressure test.

 

[Fish]

Fuel line.

Look at the area where it enters and exits the tank. If so, you should go through the carb as well.

 

[Erick]

I agree.... with everybody.

Sounds a bit dramatic for a crank seal, but if you've eliminated the fuel hose I'd go for a pressure and vacuum test on the crank case. Of course if you have the means to do this test..... pressure test the fuel line first.

 

[Arrowhead]

Same here, everybody read my mind. Im sure its one of the things mentioned.

 

[mpc855]

Thanks for the suggestions everyone. I don't really know much about engine repair, so the vacuum and pressure tests are out for now. I'm going to try putting a new fuel line on the machine and see if that helps, but I'm trying to understand the logic behind it (not questioning anyone's expertise, just trying to get an understanding): If the problem is consistent whether the tank is almost empty or completely full, wouldn't that rule out a fuel line crack? If the line was completely submerged, it seems like a crack in it wouldn't have any effect.

On a separate note, I need get back to cutting trees, so I'm going to pick up a new saw today or tomorrow and tinker with the 340 in my spare time. I've been happy with the 340 up to now; it's small, maneuverable, lightweight, and has cut nicely through thousands of small trees (3-6"), but they don't seem to sell the 340 in my area anymore. Lowes carries a 435 that looks about the same size as my 340. If I've been happy with the 340, do you think I'll like the 435? Other suggestions are welcome too.

Thanks again for the help.

 

[Taxmantoo]

Hundreds (thousands?) of Ryobi 10532s got returned and hit the refurbished market because the fuel line was too long and stiff, it held the fuel filter/pickup hard against the left side of the tank. If you turned the saw bar down, it would die.

 

[mpc855]

Actually I forgot about two other things, which Fish's and taxmantoo's posts just reminded me of:

The weighted fuel filter sits by default on the bar side of the saw, so if anything I would expect the problems to occur when the saw was tilted bar side up. And the saw has been running fine for about two years; this problem just started showing up in the last week or so.

Also, after I inspected the fuel line, I reversed it, so if there was a problem around the point where the line entered the tank, that point should now be be submerged when the tank is full. (The portion of the line that is outside the tank is relatively short; most of the line sits inside the tank.)

Oh, one other thing I just noticed is that the saw has left a small puddle of lubrication oil on the floor where it was sitting for the last hour, and I've never noticed anything like that before. Is that just because I've been running it without actually cutting anything while doing all these tests?

 

[Taxmantoo]

Oh, one other thing I just noticed is that the saw has left a small puddle of lubrication oil on the floor where it was sitting for the last hour, and I've never noticed anything like that before. Is that just because I've been running it without actually cutting anything while doing all these tests?

Sounds feasible. If I spend too much time playing with a saw trying to get it to run right, the clutch cover tends to collect oil inside.

 

[outdoortype]

Sounds like an air leak

I've heard that it isn't unusual for a saw change a couple hundred rpms when laying it on it's side. But if it's dramatic enough that the engine starts to race or immediately stall out its most likely an air leak. I've read several threads/posts reguarding these symptons and usually the air leak causes the saw to stall when laying on it's saw. What I'm wondering if it's feasable to spray some soapy water on the crank seal area without removing anything major or blocking of the cylinder? Would it show bubbles around the leak just by rotating the crank back and forth?

 

[harveylogging]

Spray carb cleaner on where u think an air leak is present. If there’s one the motor will die. A little tricky on the or around the carb side though. It will get sucked in the air cleaner and kill it .

 

[Okie]

If you loosen the tension on the chain or take the chain off and the symptoms change somewhat this is a hint that the clutch side seal is going bad.
Sometimes doing this will also cause the idle to change little bit.

A chainsaw that changes run symptoms when doing the tilt test is also a indicator of crankshaft seal leaking. The oil on the floor is no concern. It just bar oil from your messing around with the saw.
You say you are going for a new saw. You can you tube videos of how to test for crankcase seal leaks and play with the saw in your spare time. If you use a chainsaw very much you need a spare saw anyway and being able to do chainsaw repairs is also a plus.

 

[EchoShindaiwaMakitaDolmar]

Spray carb cleaner on where u think an air leak is present. If there’s one the motor will die. A little tricky on the or around the carb side though. It will get sucked in the air cleaner and kill it .

I hope he got it fixed in the 13 years since he started the thread.

 

[Okie]

I hope he got it fixed in the 13 years since he started the thread.

We are still here for him.

Hope his new saw is also still running.

 

[sonny580]

I have that problem on one of my Blue Max saws,---turnes out to be fuel line dont follow the gas all the time. That line has to not only be flexable, but the filter has to be the weighted type. At least that is what I found on all brands of saws.

 

[thenne1713]

FIRST item to check is that FUEL FILTER STILL ATTACHED INSIDE FUEL TANK, then verify that line still flexible and not cracked, and that filter falls to low point properly as saw is rotated.

 

[singinwoodwackr]

12 yrs later…probably sold it, lol