Husqvarna 372xp Chain Won't Stop Spinning

[BSS]

Hey all, new poster/chainsaw operator here! My wife and I recently moved to a house with wood as the primary heat source, so I’ve been getting into the swing of things with splitting and cutting wood. I’ve been lurking around here for a little while, but I’ve run into an issue and I’m hoping this community can help steer me in the right direction!

By virtue of a friend with a lot of experience, I recently ended up getting a beast of a saw, a new Husqvarna 372xp. The saw has been awesome, eating through red oak logs like butter! Unfortunately, as someone relatively new to chainsaws, I realize this saw in particular is quite a large undertaking. I’m trying to do everything as “properly” as I can, following manual recommendations, etc because I really don’t want to screw anything up.

That being said, I managed to run into some issues after only about 2 hours of use (not bad eh?). Initially, I noticed the idle was starting to act weird, with the engine ‘hunting’ every few seconds. After some research (on this forum) I realized that the carburetor probably needed to be adjusted. Well, the manual says to take it to a professional, so naturally I decided to attempt this on my own without a tachometer. I ended up with a saw that seemed to idle stably, but the chain would continue to spin for a few seconds after the throttle was released. The longer the throttle was held down, the longer it would take for the chain to stop spinning.

I finally got my hands on a tachometer and attempted a second round of carb adjustments, which didn’t end up much better than my first attempt. You can see my lackluster results in the link below:



Whenever I tried to lower the idle speed down to the recommended setting (2700) the saw sputtered/raced at idle and bogged down like crazy when I tried to give it gas. I couldn’t seem to find the sweet spot at the proper rpm that was both responsive and\or didn’t hunt every few seconds. As a result, the most “stable” idle I could achieve was actually about 1000rpm over recommended, or about 3700rpm - oops. I’m hoping this issue alone is what is causing the chain to continue spinning when I release the throttle, but I’m at a bit of a loss now because I don’t know if I’m just tuning it totally wrong or if there is some other underlying issue I’m not aware of. I did see the clutch could be a cause, but again, the saw is brand new and it seems like the engine is just reluctant to slow down after throttle release.

I did some more research last night and found the "#7954" detailed post on carb tuning, so I think I’m going to try once more again today, hopefully with better results than last time. That being said, I wanted to post here and see if you folks have any recommendations and/or know any other possible causes I should look into. Is this something I should continue attempting to fix myself or should I just bite the bullet and take it to a dealer? I’m hoping to avoid the nuclear option as I would like to learn proper maintenance on my own!

Thanks for reading if you made it this far!

 

[boltonranger]

Very nice saw. Did you possibly adjust a carburetor mixture screw instead of the idle speed screw? There are three adjustments in there

 

[Brian72]

Hey all, new poster/chainsaw operator here! My wife and I recently moved to a house with wood as the primary heat source, so I’ve been getting into the swing of things with splitting and cutting wood. I’ve been lurking around here for a little while, but I’ve run into an issue and I’m hoping this community can help steer me in the right direction!

By virtue of a friend with a lot of experience, I recently ended up getting a beast of a saw, a new Husqvarna 372xp. The saw has been awesome, eating through red oak logs like butter! Unfortunately, as someone relatively new to chainsaws, I realize this saw in particular is quite a large undertaking. I’m trying to do everything as “properly” as I can, following manual recommendations, etc because I really don’t want to screw anything up.

That being said, I managed to run into some issues after only about 2 hours of use (not bad eh?). Initially, I noticed the idle was starting to act weird, with the engine ‘hunting’ every few seconds. After some research (on this forum) I realized that the carburetor probably needed to be adjusted. Well, the manual says to take it to a professional, so naturally I decided to attempt this on my own without a tachometer. I ended up with a saw that seemed to idle stably, but the chain would continue to spin for a few seconds after the throttle was released. The longer the throttle was held down, the longer it would take for the chain to stop spinning.

I finally got my hands on a tachometer and attempted a second round of carb adjustments, which didn’t end up much better than my first attempt. You can see my lackluster results in the link below:



Whenever I tried to lower the idle speed down to the recommended setting (2700) the saw sputtered/raced at idle and bogged down like crazy when I tried to give it gas. I couldn’t seem to find the sweet spot at the proper rpm that was both responsive and\or didn’t hunt every few seconds. As a result, the most “stable” idle I could achieve was actually about 1000rpm over recommended, or about 3700rpm - oops. I’m hoping this issue alone is what is causing the chain to continue spinning when I release the throttle, but I’m at a bit of a loss now because I don’t know if I’m just tuning it totally wrong or if there is some other underlying issue I’m not aware of. I did see the clutch could be a cause, but again, the saw is brand new and it seems like the engine is just reluctant to slow down after throttle release.

I did some more research last night and found the "#7954" detailed post on carb tuning, so I think I’m going to try once more again today, hopefully with better results than last time. That being said, I wanted to post here and see if you folks have any recommendations and/or know any other possible causes I should look into. Is this something I should continue attempting to fix myself or should I just bite the bullet and take it to a dealer? I’m hoping to avoid the nuclear option as I would like to learn proper maintenance on my own!

Thanks for reading if you made it this far!

I'm sort of an amateur myself but I'll try to relate what I've learned. Turn idle up until chain starts spinning then back it down till it stops and you have a nice smooth idle. As far as throttle response, I believe that is more controlled by the L adjustment. After setting the idle, work on the L adjustment to get a good, snappy trigger response. Make very fine adjustments. It doesn't take much to make a big difference. I'm sure others will be along who are much much more experienced but this has worked well for me. There are also some very good videos on YouTube to help better understand the process.

Sent from my E6782 using Tapatalk

 

[BSS]

Very nice saw. Did you possibly adjust a carburetor mixture screw instead of the idle speed screw? There are three adjustments in there

Yes, I adjusted the idle (T) and the low carb setting (L). I left (H) alone because the high rpms capped at just under 13,500.

As far as throttle response, I believe that is more controlled by the L adjustment. After setting the idle, work on the L adjustment to get a good, snappy trigger response. Make very fine adjustments.

Thanks for this, that actually helps a lot having some clarification between the idle and the low settings. I think my biggest mistake is not turning the screws in small enough increments. I'll try this out later today.

 

[Brian72]

Yes, I adjusted the idle (T) and the low carb setting (L). I left (H) alone because the high rpms capped at just under 13,500.


Thanks for this, that actually helps a lot having some clarification between the idle and the low settings. I think my biggest mistake is not turning the screws in small enough increments. I'll try this out later today.

Anytime. Again, I'm no expert but I've learned a lot from these forums. A bunch of great people always willing to help. Tuning isn't a difficult process but can be very intimidating at first. If still in doubt, don't hesitate to seek help from a good dealer. A little more knowledge never hurts. I always carry a screwdriver small enough to re-tune if necessary but seldom have to.

Sent from my E6782 using Tapatalk

 

[BSS]

Yeah, I get the impression that tuning should be relatively straight-forward, which makes me think I'm just doing something horribly wrong or there is some other issue with my saw.

Thinking back to my previous tuning experience, I never really had an issue with the chain rotating at idle, even when I cranked the idle screw way up. It's odd that the spinning issue is only present for me after throttling for a few seconds because most guides I've read suggest the spinning thing should happen while the saw is just idling. I'm going to attempt tweaking the idle down until it's closer to 2700 and then try slowly adjusting the L screw until it (hopefully) throttles well and doesn't hunt at idle speed.

 

[HarleyT]

Take off the chain and look at the clutch, make sure that the springs look OK. See if the sprocket drum spins freely, etc..

 

[Brian72]

Yeah, I get the impression that tuning should be relatively straight-forward, which makes me think I'm just doing something horribly wrong or there is some other issue with my saw.

Thinking back to my previous tuning experience, I never really had an issue with the chain rotating at idle, even when I cranked the idle screw way up. It's odd that the spinning issue is only present for me after throttling for a few seconds because most guides I've read suggest the spinning thing should happen while the saw is just idling. I'm going to attempt tweaking the idle down until it's closer to 2700 and then try slowly adjusting the L screw until it (hopefully) throttles well and doesn't hunt at idle speed.

That's pretty much the key to all of this. Knowing our abilities and limitations. I do minor repairs and maintenance but I'm not master mechanic. It's a constant learning process.

Sent from my E6782 using Tapatalk

 

[chuckwood]

Take off the chain and look at the clutch, make sure that the springs look OK. See if the sprocket drum spins freely, etc..

Also, make sure the clutch drum bearing has grease. If this bearing runs dry it can start seizing up and spinning the chain at idle rpm.

 

[Totembear]

Seeing as this happened 2 hours into cutting and wasn't happening before I am thinking that it might be an air leak. An air leak can cause an erratic idle. Check to make sure the cylinder bolts are tight and the bolts that hold the carb to the cylinder are tight. There are more things that can cause an air leak but you had better off bring it to someone who knows what they are doung to pressure and vacuum test it if all the above fail to resolve the problem. Good luck!!!

 

[sunfish]

It does sound like an air leak. But turn L screw counter clock wise, this will richen it & lower the idle.

If idle still too high, then turn T counter clock wise to lower idle.

If all else fails use your warranty.

 

[Tree94]

chain properly tensioned?

 

[cus_deluxe]

Your low speed jet is too lean i thinks, judging by the bog when giving it throttle and being a little slow to return to idle. Husqvarna website shows idle speed of 2700 rpms, yours appears to be spinning close to 3800 rpms... just this will cause the chain to spin. do you have the splined adjustment tool for adjusting the carb jet screws?

 

[BSS]

Hey all, thanks for the replies! I took another stab at tuning the carburetor again this afternoon. I feel like I got much better results, perhaps even decent, though I think there might still be some tweaks to make. Here's a video showing the saw after my second attempt:



I achieved this result mostly by lowering the idle speed from where I had it before. As you can see in the video, the saw has good responsive pickup and seems to idle stably without the chain spinning. Since things seemed to be working well, I decided to do some cutting with the saw and make sure it was actually stable. I turned off the saw and suited up and moved some logs into position for easy cutting. The saw had been sitting for about 15 minutes when I finally fired it up again. When I turned it back on, the throttle bogged down with the chain brake engaged, but had good pickup with it off. I thought it was strange but it occurred to me that I didn't test with the brake on while tuning. Since it had good pickup without the brake on, I decided to go ahead with some cutting anyway, since I had everything lined up. after a few seconds, it seemed fine - very responsive and cut well. After about 15 minutes of cutting, the saw starting hunting again, but only occasionally - I think when I held the saw at different angles other than upright.

It does sound like an air leak. But turn L screw counter clock wise, this will richen it & lower the idle.

If idle still too high, then turn T counter clock wise to lower idle.

If all else fails use your warranty.

Since I didn't mess with the L screw much on my second tuning, it sounds like maybe the bog on startup and the hunting after 15 mintues might mean it's still a little too lean. Do you still think I need to worry about an air leak? If so, I'll take a look at the bolts tomorrow!

Thanks again folks!

 

[hanniedog]

Not to rain on your parade but if it is under warranty let the dealer sort it out.

 

[huskyboy]

13k max for the xtorq's they are lower rpm than the originals. I'd be taking it to dealer.

 

[boltonranger]

I mean this only in the kindest way possible - You need someone local who is knowledgeable to explain how and why your saw works the way it does.
I'm not at all sure you have it set correctly. I say this to spare you the loss of your investment. If you are unclear on why the saw bogs when you squeeze the throttle when the chain brake is on...you should not be adjusting the carburetor at all.
Please ask your dealer all the questions you have asked here and learn the saws mechanics. He has a vested interest in your productive safe use of your machine. Even if you did not buy from a dealership. Trust that I'm only trying to keep you and your saw safe. Ignorance of its mechanics can ruin it and hurt you.

 

[CR888]

It does sound like an air leak. But turn L screw counter clock wise, this will richen it & lower the idle.

If idle still too high, then turn T counter clock wise to lower idle.

If all else fails use your warranty.

Putting the air leak possibility as side, this Sunfish post above was exactly what I was thinking. Your L speed is a bit too lean. Idle can be speed can be adjusted by both L & T screws, the fact when revving down to idle you say it takes too long usually means its lean. Maybe reset all 3 screws to factory settings and go from there.

 

[sunfish]

Since I didn't mess with the L screw much on my second tuning, it sounds like maybe the bog on startup and the hunting after 15 mintues might mean it's still a little too lean. Do you still think I need to worry about an air leak? If so, I'll take a look at the bolts tomorrow!

Thanks again folks!

Yes, but maybe the L setting is just too lean.

Also, do not adjust or give throttle when the brake is on. Bad for the clutch and impossible to read the tune.

 

[Mad Professor]

ASSuming there are no air leaks and you seem close to having it adjusted........

Well check the cyl bolts, carb bolts, intake boot, and impulse line, and the air filter seats properly and is clean, anyway.....

Turn L out until it bogs/stalls at idle, then turn it in until the chain spins, then set it halfway between the two and reset your idle screw. Now see how the saw comes off idle as you open the throttle, if it bogs, turn out the L in small amounts until the bog goes away. You may have to reset idle screw again.

If it's still squirrely, get it checked for air leaks. An air leak can trash a good saw.

Good luck.