Husqvarna 154SE - the Legend is Born

[CJ Brown]

Since I just finished rebuilding one of these, I thought I would do a thread on this somewhat overlooked saw. As far as I can tell, the 154SE was a completely new saw for Husqvarna in 1983. It may have shared a few small parts with other Husqvarnas of the same vintage, but it was essentially a stand alone version. It was also the chassis that the legendary 262XP would eventually be built upon.

As can be seen in the above photo, the saw came with a unique felling dog and a metal brake flag that was only available for 1 year, before changing to the familiar plastic brake handle.

 

[CJ Brown]

I took this saw down to the cases for cleaning and inspection purposes. The bearings were smooth so I didn't replace them. I did replace the crankshaft seals simply because they were almost 40 years old. The pto side seal was the standard metal/rubber seal, but the flywheel side seal was actually plastic/rubber, and housed in the sought after metal seal holder. The fuel tank handle is the same design with the same antivibe elements that didn't change for 20 years, with the exception of the introduction of spring antivibe on the 262XP (and later 261). The oil pump housing was plastic and didn't change to metal until the introduction of the 254. Even though the saw in the picture has a air deflector between the cylinder and muffler, that is not how they came from the factory, and requires a spacer between the cylinder and deflector to clear the cylinder fins. The cylinder fins were changed when the deflector was introduced on the 254.

 

[CJ Brown]

The flywheel side looks very familiar to anyone who has torn into the 254/257/262 series saws, with the exception of the unique fuel and oil caps - which I actually prefer as they don't seem to get stuck and are quite easy to remove by hand. If you have arthritis in your fingers you appreciate little things like that!

 

[CJ Brown]

I checked the squish before removing the cylinder and it was .032" from the factory. Timing numbers from the factory were: Intake= 73, Exhaust= 104, Transfers= 125 The combustion chamber is fairly small and offset to the intake side of the cylinder. There is no decomp.

 

[CJ Brown]

Since this particular saw had a broken top cylinder fin, I decided I wouldn't mind doing some modifications to it. It is a 'C' sized cylinder, and finding a replacement 'C' sized piston proved impossible, so I kept the original full skirt windowed piston in the saw, and simply replaced the worn ring with a Caber. However, I wasn't really happy with the full skirt design as it really blocks a lot of airflow to the lower transfers, so... out came the dremel. Along with the dremel, I also took .030" off the skirt in the lathe to get my intake timing closer to where I wanted it. I couldn't take any more than that with having freeport issues on the exhaust side, and still had to remove a small amount from the intake skirt to get to my goal.

 

[ayoungtexan]

Since I just finished rebuilding one of these, I thought I would do a thread on this somewhat overlooked saw. As far as I can tell, the 154SE was a completely new saw for Husqvarna in 1983. It may have shared a few small parts with other Husqvarnas of the same vintage, but it was essentially a stand alone version. It was also the chassis that the legendary 262XP would eventually be built upon.
View attachment 283225
As can be seen in the above photo, the saw came with a unique felling dog and a metal brake flag that was only available for 1 year, before changing to the familiar plastic brake handle.

View attachment 283228

What’s this. Does it adjust the tension on the brake?

 

[CJ Brown]

Both the piston and cylinder are Mahle. I decided to also do also do some grinding on the cylinder to try to improve the timing numbers a bit. The numbers I aimed for were approximately 80-100-120 as that seems to be a recipe that is tossed around a lot here by the pros. I slightly raised the exhaust port and along with that, widened the exhaust and intake ports to within .060" of the skirt edges. I also ground the ledge off the lower transfers to help with the flow that would now be available from the underside of the piston past the skirt.

 

[CJ Brown]

To get the squish a bit tighter I used a .010" paper gasket with Permatex Spray-a-Gasket on both sides to help seal things up. Final squish was .019" all round. Final port timing numbers were: Intake= 79, Exhaust= 101, Transfers= 121 A compression check after some idling time yielded 180psi.

These saws originally came with a governed Walbro carb, so I swapped that out for a Walbro HDA120 carb, and also bored out the restrictive air filter opening and the intake elbow. Careful work on the drill press along with some blending with the dremel resulted in a real nice open intake tract that should flow much better.

 

[CJ Brown]

Finally, the original muffler is very restrictive. It is an empty can, but has only 3 very small slits for exhaust gasses to exist, so some work had to be done there. I didn't want to hack up the original muffler, so I added a second port to a 254 muffler instead, using a removable screen and a @Red97 deflector. I also added an air deflector from a 254 between the cylinder and the muffler to help improve cooling.

 

[CJ Brown]

The flywheel has a cast in key, and is a bit difficult to file, but I did remove about 1/4 of the key for a timing advance. After that, it was just a matter of reassembly and see if it would start.

 

[CJ Brown]

Initially I had some difficulty getting the saw to start (no spark). A new coil got it going though, but then I couldn't get it to idle. @jacob j. suggested I may have an impulse leak, and when I checked the intake tract I found a leaky gasket that proved JJ to be correct - thanks JJ for the good tip!

I can't do videos unfortunately, but I did cut up a mature (dead) Ash tree on the weekend, and I must say this little 154 really rips. A little bit loud, but she revs like a banshee and has good power in the cut. I am very happy with how it turned out.

Thanks for reading,
Chris

 

[CJ Brown]

What’s this. Does it adjust the tension on the brake?
View attachment 283257

I had that completely apart, and as far as I can tell it doesn't really do anything. It may prevent the spring from accidentally flying out of the clutch cover, and it may also prevent over-travel of the arm when releasing the chainbrake. Maybe someone with more knowledge can chime in.

 

[82f100swb]

Once you put it on the saw it makes sense, and you will understand why lots of swede-o-matics have them missing.
The idea is the screw hits the top handle when the saw flexes on the mounts on a kickback and triggers the brake. If you lean hard on the saw it will trigger the brake if you have it set fairly sensitive.

 

[82f100swb]

This is from the 266 operator's manual, but the theory is the same:

 

[CJ Brown]

This is from the 266 operator's manual, but the theory is the same:

Thanks for that info - not something I have ever seen before.

 

[Canadian farm boy]

Nice work Chris. Beautiful saw

 

[CJ Brown]

Nice work Chris. Beautiful saw

Thank you Mike! I really like working on the old Huskies since they are so simple in design.

 

[82f100swb]

Very jealous of that saw. I'm completing that saw family next. Need the 154 and 257.

 

[CJ Brown]

Very jealous of that saw. I'm completing that saw family next. Need the 154 and 257.

They are definitely getting harder to find - even compared to just a few years ago. I think maybe the easiest place to find a 154SE is in the U.K. They seem to pop up on http://www.ebay.co.uk/ fairly often.

 

[82f100swb]

I got my 238SG out of England. Definitely more of those saws over there it seems.