Husky 350 Port Job

[blsnelling]

Is your washer one of the cheap ones that are just suppose to use non-flammables?

Here it is, LINK.

 

[ronT2]

Here it is, LINK.

Thats the one I also have. But like you said the solvent you put in it can cost about $10.00 a gallon.

 

[blsnelling]

Thats the one I also have. But like you said the solvent you put in it can cost about $10.00 a gallon.

The last I bought was labeled Paint Thinner, basically Mineral Spirits.

 

[blsnelling]

This little 350 really hauls the mail! It wants to turn well north of 15,000. I've got it running quite fat right now at 14,700. I tuned it where I liked it at about 15,400, but turned it down to 14,700 for a little more breakin. She pulls strong too! I'll try to get some video of it this evening in some respectable wood.

 

[blsnelling]

So….do you plan on running a 359 carb on it?

Anyone know if specs are available online for the venture size of the 346 and 357/359 carbs? I can't get my calipers in there without removing the throttle plate and rod. I'm not going to do that.

If I get energetic enough, and find the time, I may make timed cuts with this 350, then swap the 357 carb from my 346 and see if it makes any real difference. I've always wanted to know.

 

[Mastermind]

Anyone know if specs are available online for the venture size of the 346 and 357/359 carbs? I can't get my calipers in there without removing the throttle plate and rod. I'm not going to do that.

If I get energetic enough, and find the time, I may make timed cuts with this 350, then swap the 357 carb from my 346 and see if it makes any real difference. I've always wanted to know.

Well now brad in the interest of science you know you must do this. I'll be watching for it...lol.

Thanks Brad for sharing your builds with us newbies.

After porting the 359, I'm impressed with the power these Huskys are capable of producing.

 

[ronT2]

The first thing I noticed after the mods was the throttle response.

Here's the carb info.

2150 Zama C3-EL32 15.0mm venturi
350 Zama C3-EL18 A/B 15.0mm venturi
You’ll have to use the look-up page below to verify.
http://www.zamacarb.com/prod_lookup.cfm

350 Walbro HDA-195 Carb: 15.08mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D195%2D1

2159 Walbro HDA-175 16.66mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D175%2D1

357 Walbro HDA-198 16.66mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D198%2D1

 

[blsnelling]

The first thing I noticed after the mods was the throttle response.

Here's the carb info.

2150 Zama C3-EL32 15.0mm venturi
350 Zama C3-EL18 A/B 15.0mm venturi
You’ll have to use the look-up page below to verify.
http://www.zamacarb.com/prod_lookup.cfm

350 Walbro HDA-195 Carb: 15.08mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D195%2D1

2159 Walbro HDA-175 16.66mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D175%2D1

357 Walbro HDA-198 16.66mm venturi
http://wem.walbro.com/walbro/product2.asp?Series=HDA&partnum=HDA%2D198%2D1

Excellent info. Thank you very much. If I got with a 357/359 carb, I'll be using the replacement Zama C3-EL42. It has an even bigger 17mm venturi

 

[blsnelling]

The significant difference in venturi size pushed me over the edge. I ordered a Zama carb. This is the correct replacement carb for the problematic Walbro carbs. I'll have to order the intake elbow and an air filter as well. Only $50 for a new carb.

 

[blsnelling]

If I did the math right, a 17mm venturi has 28% more surface area than a 15mm venturi. Maybe this mod makes more difference than I thought. I just threw it on my 346 since I knew I could. I never tested the difference it made alone.

 

[ronT2]

It’s a tight fit in my 2150, I hope there’s enough room in the 350. The filter is only held in place by a piece of medium density foam glued to the filter that presses against the cover when it’s on the saw. I’d still like to do some work to the elbow to give it a little clearance with the back of the case.

 

[blsnelling]

I had the 350 out tonight in some solid Oak I just dropped. It was running real good and then went crazy lean. I don't know if it's an air leak or a fuel supply problem. I did notice when blowing it off afterwards that the tank vent had fallen, but doubt that could cause it. So I didn't get to make any good comparison cuts of it against the 346. You will be able to see both of them in action here. Once I get the 350 back in order, I'll do some timed cuts with both.

In the vid here, the 350 is wearing a 7-pin 18" chipper chain, and the 346 is wearing an 8-pin and 16" chisel chain.


<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/EryJa61LC5g&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/EryJa61LC5g&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

 

[Mastermind]

Did you reseal the crankcase where the plastic and metal meet? The one I did leaked badly in that area.

 

[blsnelling]

Did you reseal the crankcase where the plastic and metal meet? The one I did leaked badly in that area.

That was not taken apart. Maybe it needs to be

 

[ronT2]

Might want to check the tank vent since it probably has a much healthier appetite for mix than it did before. The vent might not be able to keep up like on the 346(?) you had. My 2150 was not venting as fast as it had to either.

 

[blsnelling]

Might want to check the tank vent since it probably has a much healthier appetite for mix than it did before. The vent might not be able to keep up like on the 346(?) you had. My 2150 was not venting as fast as it had to either.

I already drilled the extra hole like I do on a 346.

 

[ronT2]

A lot of people look at these threads as "how to" threads, so with that in mind, I'd like to raise a few points simply to provide an alternative viewpoint for discussion, not as a criticism of the work Brad was kind enough to share.

You'll read a lot that a rough finish does not have much of an effect on flow, which is true, but there is a big difference between a rough finish, and an uneven finish. I'm sure the camera exaggerates the effect, but if you can see the tracks of the burr, then the finish is uneven enough to produce eddies that do have a negative effect on flow. Given the overall improvement in flow from the port work itself, this might be marginal, but one side effect of the eddies is carbon buildup. You don't need a mirror finish, but the surfaces should be even for maximum flow.

You can say it doesn't matter, but the people that have flow benches seem to think it does...



Like the 440? I don't like the squareness of the port edges, because it can be hard on the rings (or catastrophic if a ring hangs). That doesn't mean it won't work out fine in most cases, but the risk is real.

Another consideration for port shape, however is symmetry. With one round profile and one square profile, the ring gets forced back into the cylinder unevenly. This can stress the ring, because it is not free to move, and can cause the ring to bear unevenly on the pin, to the point of working it loose with enough use.

Speaking of symmetry, the only real danger to working on the transfers is producing a lack of symmetry. If one flows better than another, the efficiency of scavenging drops off dramatically. The saw won't run noticeably poorly, (especially at high rpms) but it will be a ways from optimal. If you are going to work on the transfers, you should find a way to test whether they have symmetrical flow.

Thanks for the info, I'll keep that in mind while I'm working/playing.

 

[sprung22]

Looks great Brad.Sounds even better...

 

[mweba]

Easy to check the side tranfer access caps for a leak. On the first 359 I did after a couple tanks the cap started to leak and gave the same symptoms. Not sayin thats it but easy to test.

 

[blsnelling]

Easy to check the side tranfer access caps for a leak. On the first 359 I did after a couple tanks the cap started to leak and gave the same symptoms. Not sayin thats it but easy to test.

That's a real possibility. I scraped the gaskets off and used MotoSeal. I'll be pulling it back down for close inspection before running it again.