Husky 350 TLC

[JeffWischer]

Hello. Brand-spanking newbie here! So here goes...
Bought the 350 new around 2002. Great saw for the bigger jobs I did on my farm in Kansas, where I no longer live. The "Big D, and I don't mean Dallas...". But it can still be handy when big oaks die in Northeast Illinois, to be converted to firewood. Won't start, but it sat for too many years during the Big D aftermath... Started looking for carb clean/overhaul videos. Ran across Matthew OIson's many great videos, especially to learn about the air leaks which can eventually affect 350's. (And found this forum in the process.) Don't believe it has the leaks yet. I have accumulated parts for the TLC it's ready for- carb kit, clutch drum/sprocket, the boot with metal clamp for the potential leak at the plastic clamp, etc. (I'm not interested in any "porting" or compression boost- stock performance is fine.) Might round-off some edges as Matt suggests in his videos, once I'm holding the head. Will see...

My question is this: regarding the potential air leak between that next piece down, the bearing cup or whatever, and the crankcase? Matt says this happens if the bolts came loose. Do I need to pull it and re-seal if there is no leak? What about removing the bolts one at a time, using blue loctite, and reinstalling them to proper torque? (I have a shop manual but haven't searched for those torque specs yet.) I'd rather stop at removing and re-mounting the head, if I can stop there.

Thank you.

 

[hacskaroly]

My question is this: regarding the potential air leak between that next piece down

Best bet for air leaks will be to pressure/vacuum test. If you pressurize the cylinder (blocking the intake and exhaust) then you can spray soapy water around the seams, screw holes and oil seals. If you have a leak, you will see bubbles. You are correct, bolts can come loose, especially if someone else has worked on the saw. Typically I find that if the bolt was still in there from the factory, when you pull it out it will have a type of lock-tight on it. I will reapply the lock-tight when putting the bolts back. If you are going to pull the cylinder off, then you will most likely want to have a new gasket to throw on there, sometimes they survive removal, sometimes not.

Depending on the use the saw had or the conditions it has sat in, it might be worth your while to replace the oil seals. The rubber on them can harden up over time and leak air. Replacing oil seals is relatively easy and give you an opportunity to inspect your bearings.

Matt has some great videos and even sells a great tool for reinstalling cranks, I have a set and have used it on five saws so far, makes doing bearing swaps a breeze! - Same here, I am not interested in porting saws, all of mine are stock!

Edit: Welcome to the forum!!

 

[JeffWischer]

Thank you! I will consider the seals, seriously. This is an in-for-a-penny, in-for-a-pound process!

The saw is still intact. Never worked on, other than a tune-up at Pioneer Farm and Ranch, Abilene Kansas,10-15 years ago, as a Christmas present from one of my sons. It has been used but well-maintained, with clean air filters and quality premix fuel. Ran fine until "parked" a few years back. So what I know of the internals are from Matt's videos. But I think that you answered my original question in this way: The o.q. was do I pull the bearing cup if it's still tight and factory sealed, no leak. Or just make sure screws/bolts are tight; not even remove. But I'm guessing that I will remove it to do the crankshaft oil seals, right? Which the more I think about it I should. I turn 71 in July. I only plan to do this once! Saw will be used for sure, but very intermittently.

 

[JeffWischer]

Oh yeah, I have the cylinder base gasket.

 

[JeffWischer]

Is the seal part of the 5039323 "Bearing Cage"?

 

[hacskaroly]

The saw is still intact. Never worked on, other than a tune-up at Pioneer Farm and Ranch, Abilene Kansas,10-15 years ago, as a Christmas present from one of my sons. It has been used but well-maintained, with clean air filters and quality premix fuel. Ran fine until "parked" a few years back. So what I know of the internals are from Matt's videos. But I think that you answered my original question in this way: The o.q. was do I pull the bearing cup if it's still tight and factory sealed, no leak. Or just make sure screws/bolts are tight; not even remove. But I'm guessing that I will remove it to do the crankshaft oil seals, right? Which the more I think about it I should. I turn 71 in July. I only plan to do this once! Saw will be used for sure, but very intermittently.

Looking at your original post again, since the saw has been sitting for a few years, you might consider working on the carb first, the diaphragms might be kind of crispy and will need new flexible diaphragms. Carb kits generally run about $15-$20. You can also first take off the spark plug, spray some WD-40 (or even pour in a little fresh mix fuel) in the cylinder, put the plug back on give the saw some pulls to see if it will pop or run for a second on the available fuel - if so, then yeah, I would look at putting in a carb kit first.

If you can get it running with the carb fix, then while running you can spray non-flammable brake cleaner around the oil seals and cylinder base to check for leaks, if there are some, then the saw will suck in the brake cleaner and the saw will stop (no damage to the saw doing this), if the saw keeps running while you do this, then you don't have any air leaks and thus will not need to do a oil seal change. For giggles, you can still go ahead and test for bolt tightness by giving all of them a quick tighten, though if they are still in good shape, none should move.

 

[hacskaroly]

Is the seal part of the 5039323 "Bearing Cage"?

Below, the red box is the bearings and the yellow box is the oil seals. Since this is what they call a clamshell saw, it appears you have to take the cylinder off to get the oil seals off and the new ones on. These are a little different to replace than non-clamshell cases where you can generally pry out the oil seals without taking the cylinder off and put the new ones on.



It appears that the bearing and seal are of the group part number 5039323-02.


Here is a link to the .pdf IPL for your reference: Husqvarna 350 IPL

 

[JeffWischer]

Yes, Thanks again. I suspect that the carb was not opened up and re-done 10+ years ago, and those diaphragms get brittle. See first post- have carb kit and will do the carb. While you were responding, I went to HL Supply and entered that part #. What Husqvarna calls Bearing Cage HLS lists as the Crankshaft Seal, so that question is answered too. It's too cold to work in my garage shop right now- 20's overnight and 40-ish daytime. But that will change in a week or so. I'll check back in when she's running!

 

[hacskaroly]

I'll check back in when she's running!

I look forward to hearing how it goes!

 

[JeffWischer]

Oh-your second post came in while I was typing. So I'm figuring this out in real-time as you are sending the info! Fantastic. Many thanks!

 

[JeffWischer]

Thanks for everything hacskaroly.
More parts coming in. So now I'm taking her all the way down. But no point to do all of this work and then have 25 year old crank seals start leaking!

As I'm learning by reading and watching, a few more questions have presented themselves:
There are different piston diameters mentioned. Do these correspond to the various displacements of this "family" of saws- 340,345, 346, 350, etc.- or is there more to it?
In a few days I'll open her up. This saw is from 2002. Will I have a dished piston? If so, and I'm happy with the power, and it all looks good, should I leave well enough alone?
Matt Olson mentions different red Loctite #s for under that bearing cup base. What about a thin layer of silicone gasket maker? (Yes, be sure it's gas/solvent safe.)

 

[hacskaroly]

As I'm learning by reading and watching, a few more questions have presented themselves:
There are different piston diameters mentioned. Do these correspond to the various displacements of this "family" of saws- 340,345, 346, 350, etc.- or is there more to it?
In a few days I'll open her up. This saw is from 2002. Will I have a dished piston? If so, and I'm happy with the power, and it all looks good, should I leave well enough alone?
Matt Olson mentions different red Loctite #s for under that bearing cup base. What about a thin layer of silicone gasket maker? (Yes, be sure it's gas/solvent safe.)

No worries, we are all learning as we go! Yes, piston sizes differ between saws, though there are some exceptions where the crank shaft may be shorter or longer to make a difference, but for the most part, you want to match the piston size to the cylinder size you have. For example, this site is listing that the piston and cylinder can be used on the 346, 350 and 353 saws.


When it comes to using locktite or gasket maker, that is usually personal preference. I use Locktite on screws where it is important they don't back out due to vibration (such as muffler bolts, cylinder bolts or bolts behind the flywheel or clutch). I don't use gasket maker between my cylinders and the crank case, but I will coat the gasket with aviation form-a-gasket to help seal the surface and to prevent the gasket from sticking and ripping in the event I have to take it apart again. Though when working with clamshell cylinders, I do use a gasket maker between the two metal halves since there isn't a gasket used.

 

[JeffWischer]

Thanks. Yes, I use Loctite on bolt/screw heads as appropriate. I hadn't previously known of using it as a surface sealant, although I can imagine that it would work to provide a thin film that won't leak. It's just too cold in the garage to open the saw up- just a few more days. Anyway, from the diagrams and videos, the bearing "cup"-holder that sits over the crankshaft rests on the plastic lower housing, and this is what Matt uses locktite for. But I imagine that any thin film of gas/oil resistant "sealer" would work.

On the piston diameter, if different displacement engines use the same cylinder and piston, then the different displacements would be a function of stroke, not bore? Which would mean that the difference is the crank?

 

[hacskaroly]

then the different displacements would be a function of stroke, not bore? Which would mean that the difference is the crank?

One would think so, but on this I am not an expert, its possible it is the reason for some, but then looking at this crankshaft here, would indicate that something else is the factor:

 

[farminkarman]

One would think so, but on this I am not an expert, its possible it is the reason for some, but then looking at this crankshaft here, would indicate that something else is the factor:

View attachment 456394

All the saws listed plus more red saws use the same stroke. The difference in displacement comes from different bore sizes. OE 346xp, 340, and 345= 42mm bore; early 350's and 351's used an open-port 44mm; NE 346xp use 44.3mm bore; later 350's and 353's use the 45mm bore cylinder with removable transfer caps.

 

[hacskaroly]

The difference in displacement comes from different bore sizes.

The info is much appreciated!! Sometimes it gets confusing trying to mix and match parts and I don't have enough experience yet with them to know off hand.

 

[JeffWischer]

Yup. Since I asked the question, I was going through my recently down-loaded shop manual and there it was on page 7. Stroke is the same; bore accounts for the displacement. And model number (last two digits) may or may not approximate the displacement as you pointed out. So my "early" 2002 saw, if it ever needs a piston, will require the one specific to its serial number.

 

[thedude74]

It's pretty easy to tell the difference in the 44mm and 45 mm cylinders with the hood off. As mentioned the 45 mm has removable transfer caps. The 44 does not.
The oem 45mm piston is a dished type. A flat top piston from a 351/353 can be swapped in for a performance boost(more compression).

If you really want it to run amazing....send it to @farmankarman to have it ported.