Thinking About Buying a Husqvarna 3120

[IH1972]

I've been thinking about buying a 3120 to use with my Granberg mill as a dedicated power source. I'm currently using a 395, and I like it for regular cutting but I can't when it's tied up on the mill. Also, the 395 chain tensioner is a real pain in the neck. It's bad enough when not in the mill, but when in the mill, it's just about impossible to get to. I understand that the 3120 has a tensioner on the outside of the bar making for easier access. I have other saws that are better suited for firewood, etc. and this would be more in the realm of toy/hobby than something I'm going to try to make money with.
I also like that the 3120 has an adjunct oiler.

I'm curious how the current production saws compare with the ones from years past. I've done quite a lot of reading and understand some of the changes that were made such as a limited coil, non-adjustable high jetting in the carb, etc., all of which can be remedied. I've seen a few older saws offered for sale here and there, but I'm somewhat nervous about getting such an expensive saw used. I'll roll the dice on the smaller saws I like, but even a cheap used 3120 is going to be $6-700 and I don't want to buy someone else's problems.

The other thing that's making me think now is a good time to get one is the fact that I keep hearing that they are going to discontinue this model, probably sooner than later, and if I ever want a new one, this is the time.

Before someone says it, I'm not interested in a Stihl 881.

I would be interested in other's opinions and experience with the 3120 new vs past models.

Thanks!

Here's a random photo I found on the internet:

 

[dall]

what size boat do you have ?

 

[jacob j.]

I would be interested in other's opinions and experience with the 3120 new vs past models.

I believe the current models have the semi-fixed jet carburetor and rev-limited ignition (10.5k?) - there are guys here that know a lot more about that than I do (@srcarr52 ).

The early 3120s are great saws - @dall even has one that he runs when he's tired of his Redmax.

The main difference between the tensioners on the 395 and 3120 is that the 395's is in the case whereas the 3120's is in the clutch cover.
If you want that style of tensioner on your 395, you can modify a used 3120 clutch cover to fit on your 395. A local guy here that mills has
that set-up. The 3120 is a great saw for a mill but you have to watch keeping the tune in line with the rev-limited ignition.

 

[drf256]

I purchased one for milling and was using a ported 395XP prior.

I will say that unless you are going for routine milling cuts that are wider than 36”, there is no need for the 3120. My ported 395XP seems to work just as well.

As for the 3120, I bought a new one. The new one comes with the green limited coil (9.5k IIRC) and a flywheel with different timing than the earlier black coiled models. A 272 coil is plug and play, exc for some minor grinding of the coil leg for the larger 3120 flywheel radius. I believe nearly all one-piece coils for the 2 series are the same part, I know a 272 coil fits a 262XP and other 2 series. If you get the older style flywheel and coil on the 3120, the flywheel needs to be re-indexed nearly 180* from how it will sit stock.

I went with a modded carb for the H jet from @Mastermind. @Moparmyway ported both my 395 and my 3120.

Being I only have a 36” mill, my 3120 sits most of the time. My only use is when I borrow my buddy’s 5 foot bar for extra big stuff.

 

[IH1972]

I'm either going to get another 395 or a 3120 as I want a powerhead that I can leave in my mill. I want to keep my current 395 free for felling, etc.
If I get a 3120, I would definitely swap out the coil and have the carburetor modified.

 

[srcarr52]

The best solution for the tensioner on the 395 is to drill the bar and bolt it to the mill instead of running the clamps. Then you can cut off the part that gets in the way of the tensioner. Plus, if you drill through the center of the bar tip you get a few extra inches of cut width. I think with a 36" bar on a 395 I could get 32.5" of cut width this way.

You can also pull the tensioner screw out deepen and widen the original slot and then make a similar slot at a 90° to it. This way you can always get the screntch on it at more of an angle and the second slot helps clear the screntch head at times.

 

[IH1972]

The best solution for the tensioner on the 395 is to drill the bar and bolt it to the mill instead of running the clamps. Then you can cut off the part that gets in the way of the tensioner.

I've considered drilling the bar for mounting the mill, but the mounting pad is still directly in front of the tensioner screw. If I were to cut it enough to allow access, the mounting pad would essentially be cut in two and it's only welded at either end. That wouldn't be a problem normally, but the mill is galvanized and I don't want to have to weld on it.
I've looked at it from all angles believe me and I've come to the conclusion that if they planned to put the tensioner in the worst spot possible they couldn't have picked a better spot.
One thing that I plan on doing is welding an acorn nut on the tensioner so I can at least use an extension with a swivel socket to get to it easier. Using a regular screwdriver on it is a pain.

 

[Shane¹]

When I used my mill on my 9000 with front tensioner I drilled a hole through the mill and used a thin screwdriver worked pretty well

 

[IH1972]

When I used my mill on my 9000 with front tensioner I drilled a hole through the mill and used a thin screwdriver worked pretty well

See my above post about why that's not a good option for me.

 

[srcarr52]

I've considered drilling the bar for mounting the mill, but the mounting pad is still directly in front of the tensioner screw. If I were to cut it enough to allow access, the mounting pad would essentially be cut in two and it's only welded at either end. That wouldn't be a problem normally, but the mill is galvanized and I don't want to have to weld on it.
I've looked at it from all angles believe me and I've come to the conclusion that if they planned to put the tensioner in the worst spot possible they couldn't have picked a better spot.
One thing that I plan on doing is welding an acorn nut on the tensioner so I can at least use an extension with a swivel socket to get to it easier. Using a regular screwdriver on it is a pain.

Nothing says you have to drill the bar in the center and that your bar has to be aligned with the mill posts.

I made my own mill so my posts to the bar were drilled/tapped from the start, but I drilled two holes on the powerhead side offset from the center to help miss the tensioner.

It maybe a terrible location for a tensioner, but it's the same location as all the other 2 series and previous Husky saws. It's simple and effective.

FYI. 5/16" bolts have a 1/2" head which is close enough to use a 13mm screntch.

There is some room on the tensioner for a nut, you might be able to drill the center out of a smaller nut slip it over the outside of the tensioner. This way you can still use a screwdriver when not on the mill.

 

[IH1972]

Plus, if you drill through the center of the bar tip you get a few extra inches of cut width. I think with a 36" bar on a 395 I could get 32.5" of cut width this way.

I've read about doing but haven't ever actually seen it done and am unfamiliar with how that bearing is configured. It sounds like a good idea to maximize cut width.
Is drilling the tip a possibility with most roller tip bars? I've got an Oregon bar.

 

[srcarr52]

I've read about doing but haven't ever actually seen it done and am unfamiliar with how that bearing is configured. It sounds like a good idea to maximize cut width.
Is drilling the tip a possibility with most roller tip bars? I've got an Oregon bar.

It is if you go really slow rpm with a good drill lubricant and lots of pressure. I normally use a #4 carbide center drill.

 

[IH1972]

It is if you go really slow rpm with a good drill lubricant and lots of pressure. I normally use a #4 carbide center drill.

How slow are we talking? 200 rpm or?

 

[huskyhank]

If money is not a problem, I suggest you buy a new 3120 and have it worked over a bit. Mod the carb for screws so you can tune it, install an unlimited coil and open the muffler a bit. What I found is that there is no replacement for displacement and the extra CCs of the 3120 is a fair estimate of the difference between it and any smaller saws. You will find a very noticeable difference between your 395 and the 3120.

 

[IH1972]

Mod the carb for screws so you can tune it.

Do you know of a write up on how to do that?

 

[jacob j.]

Do you know of a write up on how to do that?

How To Add A High Speed Circuit To A Walbro WG Carb

This thread deals with the Walbro WG-8 Notice that there is a pilot hole here? That makes these a bit simpler.

opeforum.com

 

[IH1972]

Thanks for the link.
I've read about the swap to a 272 coil along with other mods. From looking online, it appears that the 272 and 51 (along with a bunch of other other models) use the same coil. I've got a good 51 coil. Would that be a suitable replacement instead of one from a 272?

 

[srcarr52]

How slow are we talking? 200 rpm or?

Sure, the key is to not let the bit slip on the surface and work harden the material.

 

[IH1972]

Regarding swapping out to an unlimited coil, I'm curious why that's more commonly done than swapping out to the earlier 3120 12K coil with its corresponding flywheel.
Are there not concerns about over-revving with the unlimited coil?
I understand that either option requires carburetor modification.

 

[Nutball]

As long as you can get 11,000rpm out of a 3120, I wouldn't swap the coil. Much above 10,000rpm and you might as well use a 90cc.