Husqvarna 445 Rebuild

[PeachMan]

Hi. new to the site, quite a bit of widson (& wit) here.

Background--I'm slowly getting out of the peach orchard business and have cut down/cut up a few hundred peach trees with the 445 saw. Peachwood is just below rocks in hardness, dulls a chain in no time.

The (10 year old) saw was running a bit rough last year, wouldn't start in the spring. Fuel, spark, etc, OK. Dry cold compression is 92 psi, so no wonder it wouldn't start. A shot of 90 wt. gear oil gets it to 145.

So, I'm thinking a top end rebuild is in order. Downloaded the workshop manual from this site (Thanks!) and it all looks pretty straightforward. I'm looking for advice on parts, useful upgrades, etc. Here's what I was planning to do. All OEM parts from Bailey's 'cause there's no full service dealer anywhere close.

New cylinder/piston kit, crankcase gaskets, mainshaft oil seals. Wasn't going to replace stuff that works that's easy to access from the outside (coil, carb, etc.).

Anything else or something different I should do? No need for a performance saw, just need to have my old saw back.

Thanks!

 

[Dub11]

Welcome to the forum! And it sounds like you are the right track. Maybe take a look here for your parts. https://www.opesupply.com/ its ran by the man who runs the forum. And @Onan18 might have some useful tips for these saws. Hey Joe is a bigger cylinder available for these saws?

 

[huskyboy]

450 is the bored out cylinder

 

[Dub11]

450 is the bored out cylinder

Is everything else the same?

 

[huskyboy]

Is everything else the same?

I think so. Honestly for the original poster, I wouldn’t bother rebuilding a clamshell. The amount of money wasted altogether could be used to get a decent pro saw. That’s just my opinion though.

 

[Dub11]

@PeachMan what does the cylinder look on the inside? Sometimes that can be cleaned up and saved.

 

[PeachMan]

Appreciate the info, will check out the links this PM. Re Dub11 question. I haven't taken the saw apart yet, I have a tendency to end up with a box of parts that I can't figure out how to put back together ;-). --I looked at the piston and cylinder through the exhaust port. One small scratch on the piston, other side of cylinder looks OK.

Can I hone the cylinder (& maybe use an oversize ring) to get rid of minor stuff?

I thought about getting a pro saw, but I'm phasing out of orchards & getting ready to retire, so I probably wouldn't get full use out of the new saw. Plus, if my wife found out I'd bought a new saw....

 

[huskihl]

If the cylinder isnt scarred up, its possible it just needs new rings

 

[PeachMan]

I went to the OPE website and was (pleasantly) surprised that the whole works plus a new fuel line was $100. figure I can't go wrong at that price.

I'll post updates with anything interesting as I go along.

thanks for your help!

 

[Dub11]

I went to the OPE website and was (pleasantly) surprised that the whole works plus a new fuel line was $100. figure I can't go wrong at that price.

I'll post updates with anything interesting as I go along.

thanks for your help!

You can easily clean up the cylinder at home with some sand paper then spend $30 on a piston.

 

[usmcbuckwild]

I went to the OPE website and was (pleasantly) surprised that the whole works plus a new fuel line was $100. figure I can't go wrong at that price.

I'll post updates with anything interesting as I go along.

thanks for your help!

I am about to tear into a 445 for a friend of mine. If you need any assistance or pictures during your build feel free to hit me up.

Its not all that complicated, to be honest. I doubt you need a new cylinder unless that one scratch is a deep one. I would do as @Dub11 said; rings and a new piston. Since you are already tearing the saw down, I would toss in new bearings (544062001) and new seals (544013801) just for piece of mind. Not replacing the cyl saves you some $$$.

 

[Dub11]

Since this is a clammy I wonder if it's like a husky 340,345, 350 in a since that the bearings fall of and on?

 

[huskyboy]

350 is actually more of a pro saw with the riser block and can stuff a 346xp cylinder on her. Can put that riser on 340/345 too (they have clamshell cylinders like 455/445). 445 is like a 455, a actual clamshell. Replaced the cases and handlebar on a brand new 455 that fell off a shelf recently... kind of a pain to work on. I felt bad for the guy, could have bought a 562 with the money wasted altogether (400$ saw+ 200$ in parts). If I knew it was going to cost that much in parts, I would have told him to part it out. Good saw for what it’s for, but not really designed to be rebuilt at that price point, unless you can clean up old cylinder and throw in a set of rings.

 

[Dub11]

350 is actually more of a pro saw with the riser block and can stuff a 346xp cylinder on her. Can put that riser on 340/345. 445 is like a 455, a actual clamshell. Replaced the cases and handlebar on a 455 recently... kind of a pain to work on. Good saw for what it’s for, but not really designed to be rebuilt at that price point unless you can clean up old cylinder and throw in a set of rings.

I get all that I was wondering how the bearings fit on the crank? To me it seems nice that they slide right off. That way someone doesn't need to buy or source a puller on a cheap rebuild.

 

[huskyboy]

I get all that I was wondering how the bearings fit on the crank? To me it seems nice that they slide right off. That way someone doesn't need to buy or source a puller on a cheap rebuild.

Probably I didn’t try taking them off on the 455 I worked on as it was brand new just needed case because it was dropped off shelf.

 

[PeachMan]

Ok, this is now officially a Mystery.

Original complaint was 90 psi compression that went to 150 with a couple of ml of 90 wt gear oil. I trust my gauge (Actron), and the increase in starter rope force was dramatic, so I'm pretty sure that the compression was actually low.

Thought I'd tear it down and send pictures of the ugly damage, but there's nothing to see. Everything looks pristine (thank you high quality oil). The small amount of carbon on the piston head & combustion chamber wiped off with a paper towel. Decompression valve seat looks good, nice even ring on the valve. Old piston ring is worn by 0.002 in the radial direction. Piston ring gap is was 0.4 mm. IIRC, the spec is 1.0 mm. Ring groove was undamaged & ring moved easily. The one fine score on the cylinder wall wouldn't catch a fingernail.

Was test fitting the new piston and cylinder & the ring broke (first time for everything). So had to order a new one before I could do the rebuild. ("Dealer" doesn't stock)


Only thing I can think of is that the ring was stuck with fuel gum and the soaking in gear oil freed it up. All other theories are welcome!