jarrah
New Member
After spending the last two year following the various thread on Arboristsite I've taken the plunge and signed up..... This is my first post.
To give myself something to do in the evening I recently bought two more Husqvarna saws to keep my 394XP company (I'm located in Western Australia).
The two saws in question are a Husqvarna 55 ($60) and a Husqvarna 340 ($40 paired with a chinese saw- Baumr AG which is badged for the Australian market).
I bought both Husqvarna saws knowing they needed work. The 55 had been straight fuelled (gased) so had a badly scored cylinder (90psi compression). The bloke I bought the 340 had recently put a 350 cylinder kit on it but it was also running bad (about 90psi compression).
To repair the 55 I bought a cheap chinese cylinder and piston kit on ebay (I've worked out from the stylised logo cast on the side that it's made by Hairun [www (dot) hairunmachine (dot) com].
View attachment 279877 When it arrived everything looked OK (for the price). However when I put the ring in the cylinder it looked to be slightly bound, so I gapped it to 0.2mm (0.8mm below the 1mm Husqvarna tolerance). Soaked the ring etc in 2 stroke oil and rebuilt the engine. Everything looks OK apart from compression....only 90psi with the throttle wide open! I've poured some two stroke oil down the plug hole and it rises to just shy of 120psi.
What I have noticed is that the rings aren't a nice shiny finish but look as if they've been oil hardened with no post treatment.
There was also a similar ring with the the box of spares that came with the 340, including the original Husqvarna piston and cylinder that don't look to bad.
I'm therefore wondering if I'm not getting a decent seal between the ring and the cylinder bore and ring and the ring groove and this maybe a indicative problem with these cheap kits (both me and the bloke who rebuilt the 340).:confused2:
To try and find out if this is the case I've splashed out on a Caber ring for the 55 that is winging it's way from the USA.
I know the basic answer is 'you get what you pay for' and the 55 kit is clearly not Nikasil lined. But as these saws aren't sexy XPs but run of the mill homeowners saws I couldn't justify in my mind shelling out for a decent cylinder/piston kit.
Anyway I await the arrival of the Caber ring and the possibility of either fixing the 55, the cylinder destroying the ring or the ring destroying the cylinder bore and me becoming more frustrated!:bang::bang:
Interestingly the Baumr AG also hadn't done much if any work (there was still powder coat on the bar rails) and the compression on this was just 120psi.
I'm therefore wondering if these cheap chinese kits and saws can only manage about 120psi before blow past occurs and to get a decent seal requires a decent bore finish (Nikasil etc) and decent rings.....Little bit of Newtonian logic there!
>>>So does anyone have any experience with these Hairun kits, is there something else I should be taking into consideration (including the 0.2mm gap)....any advice is welcome!
Thanks!
Rob
To give myself something to do in the evening I recently bought two more Husqvarna saws to keep my 394XP company (I'm located in Western Australia).
The two saws in question are a Husqvarna 55 ($60) and a Husqvarna 340 ($40 paired with a chinese saw- Baumr AG which is badged for the Australian market).
I bought both Husqvarna saws knowing they needed work. The 55 had been straight fuelled (gased) so had a badly scored cylinder (90psi compression). The bloke I bought the 340 had recently put a 350 cylinder kit on it but it was also running bad (about 90psi compression).
To repair the 55 I bought a cheap chinese cylinder and piston kit on ebay (I've worked out from the stylised logo cast on the side that it's made by Hairun [www (dot) hairunmachine (dot) com].
View attachment 279877 When it arrived everything looked OK (for the price). However when I put the ring in the cylinder it looked to be slightly bound, so I gapped it to 0.2mm (0.8mm below the 1mm Husqvarna tolerance). Soaked the ring etc in 2 stroke oil and rebuilt the engine. Everything looks OK apart from compression....only 90psi with the throttle wide open! I've poured some two stroke oil down the plug hole and it rises to just shy of 120psi.
What I have noticed is that the rings aren't a nice shiny finish but look as if they've been oil hardened with no post treatment.
There was also a similar ring with the the box of spares that came with the 340, including the original Husqvarna piston and cylinder that don't look to bad.
I'm therefore wondering if I'm not getting a decent seal between the ring and the cylinder bore and ring and the ring groove and this maybe a indicative problem with these cheap kits (both me and the bloke who rebuilt the 340).:confused2:
To try and find out if this is the case I've splashed out on a Caber ring for the 55 that is winging it's way from the USA.
I know the basic answer is 'you get what you pay for' and the 55 kit is clearly not Nikasil lined. But as these saws aren't sexy XPs but run of the mill homeowners saws I couldn't justify in my mind shelling out for a decent cylinder/piston kit.
Anyway I await the arrival of the Caber ring and the possibility of either fixing the 55, the cylinder destroying the ring or the ring destroying the cylinder bore and me becoming more frustrated!:bang::bang:
Interestingly the Baumr AG also hadn't done much if any work (there was still powder coat on the bar rails) and the compression on this was just 120psi.
I'm therefore wondering if these cheap chinese kits and saws can only manage about 120psi before blow past occurs and to get a decent seal requires a decent bore finish (Nikasil etc) and decent rings.....Little bit of Newtonian logic there!
>>>So does anyone have any experience with these Hairun kits, is there something else I should be taking into consideration (including the 0.2mm gap)....any advice is welcome!
Thanks!
Rob
around the world. It's just got a brand name down under (and is sold presumably legitimately there). The guys in the Aussie thread have a very bad taste for them, they tend to last a lifetime measured in minutes instead of years.
