346XP running issues

[SkwerI]

Last month I dug out my last old 346XP from under the bench. Fueled it up, sharpened the chain and it ran like a scalded dog! I forgot how much fun that saw could be. It's been probably 10 years since I used it in production work. The Still 200T cuts everything I need up until it's time for the 372XP. If there is medium size wood it's only a couple cuts and not enough to bother with a third saw.

Anyway, it ran great the first day and 2 weeks later when I brought it on a job it would idle great but die when you went full throttle. I have done the following-
1. Replaced the plug and fuel pickup filter.
2. Rebuilt and then replaced the carb.
3. Swapped out the coil.

While swapping out the carb I noticed the impulse line was loose fitting on the nipples. Now I'm thinking that might be my issue and I wasted a bunch of money swapping out parts that were still good. I only paid for the carb ($80), the coil was a good spare I had from a parts saw. Fuel and impuls lines are all very pliable and flexible with no visible defects, but like I said the impulse line almost fell off when I grabbed it.

 

[CurSedVoyce]

I think you are on the right track.
(Edit)

 

[Nutball]

Check the intake manifold for a leak. I vaguely remember some Husqy having a boot or block that would often crack somewhere. @huskihl

 

[SkwerI]

I will check that, but like I said it absolutely rips at an idle and throttle response is crisp and instant. Then it falls flat. I can play with the choke and keep it running and revving but it never smooths out at full throttle.

 

[CurSedVoyce]

Leaning out somewhere by the sounds.
Had a open plug gap do that to me too.
Maybe air getting by the intake or carb gasket.... boot.. something

Had a loose head once too. You would not know it. Till you turned the head bolts. Just enough to let some air in. Of course it cost me a gasket. But still.sneaky bugger.

 

[Nutball]

I will check that, but like I said it absolutely rips at an idle and throttle response is crisp and instant. Then it falls flat. I can play with the choke and keep it running and revving but it never smooths out at full throttle.

It would do that because there isn't a high demand for air until high rpm is reached, then the engine puts a big draw on the leak.

 

[flushcut]

I’m leaning towards carb boot.

 

[SkwerI]

Well I gave up on it. Seems simple enough, but I do have a local small engine mechanic I can trust and it just isn't worth the headache for a saw I haven't used in production for over 10 years. He said Husqys are known for cracked fuel lines so that's where he will start I'm sure. I also informed him about the loose impulse line so he will change that as well. I will let you all know what he found when I get it back.

 

[Al Smith]

I was going to suggest a cracked fuel line myself .I get it though because some times you just have to walk away before you blow a gasket .I've got a couple like that right now that have not ran in a long time .When you amass a number of saws it's nearly a full time job just to keep them all exercised .

 

[davidwyby]

Well I gave up on it. Seems simple enough, but I do have a local small engine mechanic I can trust and it just isn't worth the headache for a saw I haven't used in production for over 10 years. He said Husqys are known for cracked fuel lines so that's where he will start I'm sure. I also informed him about the loose impulse line so he will change that as well. I will let you all know what he found when I get it back.

Send it to @huskihl... tell him to fix it and then really fix it...trust me *evil grin*

 

[SkwerI]

Send it to @huskihl... tell him to fix it and then really fix it...trust me *evil grin*

It's already ported, and a screamer. I named it 'Taz'. Just got it back today from the shop. It took a new carb and new fuel line to fix it. Probably would have figured it out myself if I had the patience, but I just don't enjoy it any more.

If I'm not mistaken, this one was ported by a guy screen name 'Timberwolf' who was a member here a decade ago. He dropped off the face of the earth and I had no luck trying to contact him several times afterward. You can still see some of his videos on Youtube under that name.

 

[davidwyby]

Wow, Timberwolf had quite the rep if I’m not mistaken, and his knowledge and sharing of it paved the way for some of the current porters I think.

 

[pigwot]

I’m glad you got it running. I think the 346XP is my second favorite Husky, right after the original 372XP. I still run my 346XP. Only issue is it gets vapor locked on extremely hot days once it really warms up. Set it aside to cool a bit and it’ll fire right up. Been too lazy to figure that out. I have about five other saws awaiting their rejuvenation.

 

[Husky D]

I’m glad you got it running. I think the 346XP is my second favorite Husky, right after the original 372XP. I still run my 346XP. Only issue is it gets vapor locked on extremely hot days once it really warms up. Set it aside to cool a bit and it’ll fire right up. Been too lazy to figure that out. I have about five other saws awaiting their rejuvenation.

I've still got 346's and the fuel caps really go tight so wonder whether the tank breather is the issue, although they have done that from new. Weather wise we don't get the heat to cause vapour lock very often, although would changing the fuel cap to the vented type that Husky fit on their brush cutters help at all? Not sure if they may be a bigger diameter although they will fit the bigger saws if you sand the cap down slightly.