HyWay - Husqvarna 359 top end

[Black Dog Chainsaw]

So I know I have seen lots of build threads pop up on here so I thought I would contribute one. I don't know how to do the port timing numbers yet, but will do all I can. Pics first...

Casting looks great.

Piston looks really good too.

Nice arch to the exhaust and pretty smooth out of the box.

Upper transfers have some pretty heavy beveling. Not bad but probably a hair more than what's needed. Same for intake and exhaust. Better to have it over sharp edges.

Lowers look smooth. Good as is but a little foredom work would improve them.

Cylinder roof looks flat with decent combustion chamber.

I always use cabers. The boxes look the same but the rings are different. I have done more than a couple hyway kits with the rings in the kits. Initial compression is good on both but the hyway kits have come back more often than not with 20-40lbs less compression and finicky starting problems. Fixed with fresh cabers and not returning.

I will check back in with squish numbers and whether or not to delete the base gasket. This will be simple swap out, no porting or fancy pants stuff. Just good rings and possible gasket delete.

 

[Black Dog Chainsaw]

I checked squish before i dropped it on and it was surprisingly 0.026 with base gasket. Not perfect but pretty good. Had plenty of power to run a 24" bar burried in red oak.

 

[Czed]

Good Iooking kit I'll try one of those next I used a big bore kit for a 372 with cabers guy requested it turned out great still running after a year but a stihl ts400 cylinder didn't have the holes drilled for the exhaust and a lot of grinding to clean it up yours looks much better.

 

[super3]

I have one of those. It's now a paper weight.

After the sq band cut the plating flaked off when blending the chamber edge.
Also flaked off around the ex & int ports while grinding.

 

[sunfish]

One of the better AM kits, but there was some problems a while back.

New OEM 359 or 357xp kits are now $120, so I'm no longer interested in the AM stuff.

 

[super3]

I bought that one b4 the price drop.

 

[Tpagel]

I have the Hyway 46mm on my 2156 and have had no trouble out of it, the casting looked much like this one out of the box...the 357XP kit was $240 at the time.
Is yours the 47mm?

 

[Black Dog Chainsaw]

Yes this is a hyway 47mm. It was also bought before my husky dealer dropped his prices. Also for my cost of these kits, there will still be some cheap guys that will ask for it. I understand there have been problems with playing before but those problems were born from tampering with the cylinder. When these get put on they are a bolt on with nothing more than a base gasket delete.

 

[Homelite410]

Sounds like the moral of the story is don't grind on am cylinders.

 

[SawTroll]

Sounds like the moral of the story is don't grind on am cylinders.

The catch with that is that you have to, to get decent performance (OK, there may be exceptions, but I haven't really heard of any).

 

[Homelite410]

The catch with that is that you have to, to get decent performance (OK, there may be exceptions, but I haven't really heard of any).

Troof

 

[Black Dog Chainsaw]

Sounds like the moral of the story is don't grind on am cylinders.

This one is not ground on... Strait from factory.

 

[Black Dog Chainsaw]

I felt the need to post the latest news on this 359.

The chrome peeled on this specific cylinder. That being said HLS has been very great and has replaced it quickly. I have installed dozens of hyway kits without this problem before. I will reinstall the same hyway 359 top end and we'll see how long the second one lasts. From past experience it seems like a fluke to me but others might say differently.

 

[Red97]

Damn, just got one of these to try out. Going to port it as well. If it dosent work out oem is cheap now.

Thank you for sharing, fingers crossed they got the issues worked out...

 

[Black Dog Chainsaw]

I think it's a fluke myself but Shaun told me to check the piston to cylinder wall clearances. He said there are instances where tolerances are a little "too" snug.

 

[Red97]

I think it's a fluke myself but Shaun told me to check the piston to cylinder wall clearances. He said there are instances where tolerances are a little "too" snug.

I will have to double check that, won't be too hard to turn down the piston a bit.

What is normal for a saw anyway? .003-4?

 

[smokey7]

I think you would be too loose at that clearance. I set up to those clearances on liquid cooled pwc motor on cast pistons and iron bore. I would take my set up numbers to .002-.003 on a saw that's new. With a ring gap around .006-.008 would be a good start. Also turning pistons is a no go at the skirt unless you have some very expensive lathe and tooling to cam cut pistons. They are not true round at the skirt.

 

[Red97]

I think you would be too loose at that clearance. I set up to those clearances on liquid cooled pwc motor on cast pistons and iron bore. I would take my set up numbers to .002-.003 on a saw that's new. With a ring gap around .006-.008 would be a good start. Also turning pistons is a no go at the skirt unless you have some very expensive lathe and tooling to cam cut pistons. They are not true round at the skirt.

Thanks for the reply.
As far as the piston cutting is concerned, if it is too tight from factory what is it going to hurt cutting it round? We are only talking .001 per side ish. The oil film is going to be most that clearance.

The way I see it if from the box last say 5 tanks because it is too tight, plating flakes off and sizes it. Or 15 tanks before the piston wears thin and breaks off, (from being undersize) which one is the better?

It will either work, or it won't. First thing is to see if the plating hold up to the porting process. If not than a oe jug and piston is the next step anyway.

Chainsaws are black magic, not rocket science

 

[smokey7]

If I was to try and make clearance in a cylinder I would use sandpaper on the piston by hand. Or if it's a larger size maybe a foam block. Keep in mind that the crown is always smaller then the skirt. Also finish in fine grit and clean it off with air. Then ultrasonic clean and blow, white glove test it.

 

[Tractorsaw1]

I picked up 1 from super3. I'm gonna put it on & see what happens.