Husky 181 lean after the cut???

[Brewz]

Hey folks
After a bit of opinion on this ported 181 I have built.
Basic woods port with single ring Hyway 281 piston, gasket delete, dual port muffler and a bit of a timing advance.
Its got a lot of compression, throwing it down struggles to turn it over to drop start it. Need to check it.
Stock carb with the flood limiter defeated.

It comes out of the cut a bit lean then idles fine.
4 stroking in the high 13000's
Cuts really strong. Last few cuts in the video I am struggling to keep the dogs off the log, which is dry 10000+ Janka Aussie hardwood.

I have not come across this problem before.
I'm worried that with the flood limiter defeated, the stock jets don't have the capacity to feed it at high revs now its ported.

What do people recon?

 

[XP_Slinger]

Richening the low jet didn't help it any? I would retune the low side. Could be out of balance between the throttle stop and mixture setting. If you've already done that I'd be looking for a leaky intake or carb mount.

Did you put new seals in the bottom end?

 

[Brewz]

Yeah replaced the crank seals.
It doesn't do it when im piss revving, only when it comes out of a loaded cut.
All new gaskets on the carb mounts.

 

[huskyboy]

How much rpm does it lean out by ? Most my saws lean out say maybe 200 or so rpm after very long cuts getting hot. I'm no expert but maybe carb doesn't supply enough fuel for the extra need the saw has after porting? That's what it sounds like. Does it keep leaning out after the second adjustment? If not then I'd just chalk it up as getting hotter which seems to be normal with a lot of saws.

 

[Normzilla]

I'm wondering if it's timing.

 

[srcarr52]

The little race bike surges as it returns to idle is pretty normal for ported saws, it's not going to hurt it.

If you really want to get rid of it, I would suggest lowering the pop off pressure a little by nipping the extra winds on the spring and make sure the metering lever is set as high as possible.

 

[XP_Slinger]

If none of the above work and your seals are in fact good I would back off the no load tune by 200rpm or so to compensate for the in the cut heat. She might just be tuned a little high.

 

[XP_Slinger]

I'm wondering if it's timing.

^^this is a very good thought.

If you advanced timing too much what you think is a 4 strokin sound could be a timing burble. Hard to tell without being right there next to ya while piss revving.

 

[Simondo]

Hey folks
After a bit of opinion on this ported 181 I have built.
Basic woods port with single ring Hyway 281 piston, gasket delete, dual port muffler and a bit of a timing advance.
Its got a lot of compression, throwing it down struggles to turn it over to drop start it. Need to check it.
Stock carb with the flood limiter defeated.

It comes out of the cut a bit lean then idles fine.
4 stroking in the high 13000's
Cuts really strong. Last few cuts in the video I am struggling to keep the dogs off the log, which is dry 10000+ Janka Aussie hardwood.

I have not come across this problem before.
I'm worried that with the flood limiter defeated, the stock jets don't have the capacity to feed it at high revs now its ported.

What do people recon?

If your sure the vac/ pressure and tune is good then I wouldn't worry. The Dolmar 9010 sounds similar when hot and being used as your showing in your Vid.

 

[Normzilla]

^^this is a very good thought.

If you advanced timing too much what you think is a 4 strokin sound could be a timing burble. Hard to tell without being right there next to ya while piss revving.

Thanks amigo. Yeah puzzling indeed. But possible

 

[Brewz]

The little race bike surges as it returns to idle is pretty normal for ported saws, it's not going to hurt it.

If you really want to get rid of it, I would suggest lowering the pop off pressure a little by nipping the extra winds on the spring and make sure the metering lever is set as high as possible.

I was thinking last night I might try raising the metering lever a bit to try and keep a bit more fuel up to it
Will give that a go.
Will also fatten it up a bit

 

[t4driller]

Does it only do it after a long cut? Maybe the tank vent is partially plugged or just not allowing enough air in causing it to go lean. Like on the husky 346 after you port them. Just a thought.

Sent from my SM-G930V using Tapatalk

 

[Brewz]

Does it only do it after a long cut? Maybe the tank vent is partially plugged or just not allowing enough air in causing it to go lean. Like on the husky 346 after you port them. Just a thought.

Sent from my SM-G930V using Tapatalk

Very good point
Will check that

 

[Chainsaw Jim]

I was thinking last night I might try raising the metering lever a bit to try and keep a bit more fuel up to it
Will give that a go.
Will also fatten it up a bit

Raising the metering lever will actually cause that lean high revving even worse. The advise that srcarr52 gave you is the procedure for your idea. The rest of that procedure would be to mod the carb so it will let extra fuel flow to match what you did to the saw. The flood limiter isn't used to prevent loading up lean, it floods the motor at a certain rpm to prevent over revving.

 

[Chainsaw Jim]

I noticed it sounded a little worse towards the end. You might check the intake block and carb mating surface for resurfacing. The blocks warp and some carbs aren't finished properly from the factory.

 

[Brewz]

I noticed it sounded a little worse towards the end. You might check the intake block and carb mating surface for resurfacing. The blocks warp and some carbs aren't finished properly from the factory.

I will give them all a bit of sealant too

 

[srcarr52]

Raising the metering lever will actually cause that lean high revving even worse. The advise that srcarr52 gave you is the procedure for your idea. The rest of that procedure would be to mod the carb so it will let extra fuel flow to match what you did to the saw. The flood limiter isn't used to prevent loading up lean, it floods the motor at a certain rpm to prevent over revving.

Raising the metering lever usually yields a 2-3 psi pop off pressure change so I don't see how it would make it worse.

 

[Chainsaw Jim]

Raising the metering lever usually yields a 2-3 psi pop off pressure change so I don't see how it would make it worse.

It lets the metering diaphragm hold the lever open sooner than it's supposed to which will cause a high idle and will have that long comedown after revving.

 

[Deets066]

Opening the needle sooner let's more fuel in last I knew

 

[Brewz]

Yeah that's what I thought too