Huztl FarmerTec MS380, MS381, 038 Build Kit Start to Finish

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Just finished another Huztl MS380 build last night. She fired on the third pull and runs well after some tuning. After shutting her down, I noticed (for the first time) that there appeared to be some extra play in the piston/con rod assembly. Remembering and reading back a bit in this thread, I note I am not the only one - and perhaps the small-end (wrist pin) bearing is not quite right. It seems that there is a degree or two of flywheel rotation at the top/bottom of the piston stroke without any corresponding movement of the piston itself. Seems to be a bit more than the normal "top-dead-center" I'm used to.

The bearing looked fine when I inserted it into the upper con rod, but I will admit to not checking it against the wrist pin before installing the piston.

Wondering what y'all think. Since it ran, and ran well, is this just my imagination working up a problem that doesn't exist? Or do I have a time bomb waiting to "grenade"? Anybody else running one of these saws with the same condition?

I do realize that it is not that hard to pull the jug and look, but I thought I'd ask before I made it a project. I don't know about you, but these things never seem to go back together as tightly on re-assembly as they do when assembling for the first time. Plus, with my luck, I'll break a ring the second time ..... :eek:
 
Just finished another Huztl MS380 build last night. She fired on the third pull and runs well after some tuning. After shutting her down, I noticed (for the first time) that there appeared to be some extra play in the piston/con rod assembly. Remembering and reading back a bit in this thread, I note I am not the only one - and perhaps the small-end (wrist pin) bearing is not quite right. It seems that there is a degree or two of flywheel rotation at the top/bottom of the piston stroke without any corresponding movement of the piston itself. Seems to be a bit more than the normal "top-dead-center" I'm used to.

The bearing looked fine when I inserted it into the upper con rod, but I will admit to not checking it against the wrist pin before installing the piston.

Wondering what y'all think. Since it ran, and ran well, is this just my imagination working up a problem that doesn't exist? Or do I have a time bomb waiting to "grenade"? Anybody else running one of these saws with the same condition?

I do realize that it is not that hard to pull the jug and look, but I thought I'd ask before I made it a project. I don't know about you, but these things never seem to go back together as tightly on re-assembly as they do when assembling for the first time. Plus, with my luck, I'll break a ring the second time ..... :eek:


Bump
 
I built a 380 and noticed a lot of slack at top and bottom of the stroke. I took apart a found they sent the wrong wrist bearing (it was for a ms440). I replaced it. I'm sure it would not have lasted long with the wrong bearing. It was obvious when I took the jug off. Not sure how I missed it during assembly.

Sent from my SM-N900V using Tapatalk
 
I built a 380 and noticed a lot of slack at top and bottom of the stroke. I took apart a found they sent the wrong wrist bearing (it was for a ms440). I replaced it. I'm sure it would not have lasted long with the wrong bearing. It was obvious when I took the jug off. Not sure how I missed it during assembly.

Sent from my SM-N900V using Tapatalk

Thank you. By "a lot of slack", do you mean more than a few degrees of flywheel rotation? When you spun the engine by hand, could you "feel" the freeplay?
 
Thank you. By "a lot of slack", do you mean more than a few degrees of flywheel rotation? When you spun the engine by hand, could you "feel" the freeplay?
It was a couple of degrees of slack. I could feel it by hand.

Sent from my SM-N900V using Tapatalk
 
Tbohn, would you recommend the 380 kit? Pondering the 360 and 380 kits
Good you got it sorted!
I have not built the ms360 or ms361 kits. I've built at least one of everything else. I think the ms660 kit is the best deal and the quality is good. I think the ms380 kits are the best quality and and most heavy duty.

Sent from my SM-G955U using Tapatalk
 
I think the had a 10mm and 12mm. The 12mm fits on the ms380 wrist pin but it's OD is too small.

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Or maybe the ID is too large...I can't remember.

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Cross pollination of the parts bins have been an on going problem.

Except for a few minor bits, this 380 went together fine.
ce833ecf0747cdc4f0fb539d2476fe41.jpg
 

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