Huztl MS660

[paul99]

Hi All,

This is my first post here but have been following the forum for quite a while especially this Huztl MS660 thread. I recently got one of these Farmertec ms660 kits and although this is my first time assembling a saw from scratch I have in the past had a number of other saws apart so thought I'd give it a go. Yesterday I got the crank case together (which was the bit that daunted me a bit but in the end turned out to me much much easier than I had expected). This morning I fitted the piston and cylinder and all seemed well but then ran across a problem whilst turning it over to check everything that has me totally confused....

With the base gasket in place and cylinder bolted down - turning the crank over by hand the saw will not reach anywhere close to TDC (or of course pass it) - the top of the piston is hitting the top of the cylinder / squish band as far as I can tell and stops with a definite metallic clunk. On releasing the cylinder bolts a little at a time (to figure out how thick a base gasket might be needed) I find that to get the saw to turn over I'd need a base gasket in excess of 5.3mm - which is clearly not right.

Here is a photo of the gap i have with the cylinder resting on the piston at TDC:

Has anyone come across this issue before and is it something I'm completely missing or is it a faulty cylinder?
Your thoughts would be appreciated...
Paul.

 

[paul99]

Having done a bit of thinking and a lot of reading it occurs to me that Farmertec make a 54mm Big Bore kit for the MS460 - I'm guessing that the stroke length would be significantly less for the MS460 - which may account for my lack of cylinder height? (if they have have indeed supplied the wrong P/C) or am I barking up the wrong tree?

Does anyone know the rough measurements for cylinder lengths for MS660 and 54mm MS460 cylinders so I can compare what I have and rule the above in /out.

 

[Bedford T]

Using a hard ruler resting on band I get 83mm deep, 56mm across on an 660 orginial jug

 

[Bedford T]

I bet it not a 660

 

[paul99]

Using a hard ruler resting on band I get 83mm deep, 56mm across on an 660 orginial jug

That helps a lot, thank you. As I thought my cylinder is short (73mm deep and 54 across / 56 including the bevel). I have emailed the seller. I am pretty sure now that I have indeed been sent a MS460 big bore P/C. I will keep you updated when I get a response.

Also in case it helps others I should point out that in my kit I have also found a few small bits missing - nothing new going by what I've read and watched in videos etc... 1 x M4 x 10mm pan head screw for oil pump, 1x Woodruff key and the nuts & bolts for the dogs. There maybe other bits as I get further along with the build.

***EDIT***
Also going by the photo mine is clearly wrong - I count 11 horizontal cooling fins on your original mine has only 9

 

[grack]

That helps a lot, thank you. As I thought my cylinder is short (73mm deep and 54 across / 56 including the bevel). I have emailed the seller. I am pretty sure now that I have indeed been sent a MS460 big bore P/C. I will keep you updated when I get a response.

Also in case it helps others I should point out that in my kit I have also found a few small bits missing - nothing new going by what I've read and watched in videos etc... 1 x M4 x 10mm pan head screw for oil pump, 1x Woodruff key and the nuts & bolts for the dogs. There maybe other bits as I get further along with the build.

***EDIT***
Also going by the photo mine is clearly wrong - I count 11 horizontal cooling fins on your original mine has only 9

Contact huztl they have been very good to me they shipped me a cylinder that wasn't tapped for the decomp.i emailed them sent photos to another address they requested they sent me two pistons and another cylinder another order they sent the wrong part's and are sending me another order right now.
Only downside is waiting sometimes over two weeks.

 

[Johnnybar]

My plastic button was very secure too...pulled hard as I could with two fingers on it and it stayed put. About half way through the 4th slabbing cut in a 10' oak log, I looked down and it was missing. The valve performed perfectly before and after it popped the button off, so I'll turn a custom aluminum replacement and lock it in place with an offset pin. When they pop they must get some good distance...never did find it. As long as the internal friction spring is holding the valve snug, I can't imagine how it could get into the cylinder...there's always positive or neutral pressure present. But I would not want to operate it long term without a button just in case the friction spring lets go.

Here is the prototype Aluminum compression release I mentioned. I wear gloves when milling but added cooling fins anyway...looks neater and just because I could...LOL It is bored for an extremely tight press fit so I may skip the offset pin for now.

 

[emanaresi]

Thats sweet! I was lucky my button fell off while the saw was idling and tuning. I found it and epoxied it back on, hopefully it stays.

 

[Johnnybar]

Press fit to allow minimal opening with secure retention in the open position. Added slight contour and increased height to blend in with the lines of 660's cylinder cover.

 

[emanaresi]

ooooh, fancy, want to send me one with those chains? I'll test it for you

 

[Johnnybar]

ooooh, fancy, want to send me one with those chains? I'll test it for you

LOL You may need one if that epoxy gets too hot and fails. I believe 300F is about all that quick set epoxy can take.

 

[emanaresi]

hmm, not sure, I used a marine epoxy... I think its a slow set, or medium... I guess we'll see how it holds up

 

[Johnnybar]

hmm, not sure, I used a marine epoxy... I think its a slow set, or medium... I guess we'll see how it holds up

Just don't let the saw get too hot... a little burble while in the cut will keep temps down considerably and let it idle a couple minutes before shutting it off after it gets a workout. Also, try to gas and oil up every 5 feet of wide slab or 8 to 10 feet of narrow slab so you never run lean. 1/3 to 1/4 tank is a good target to watch for as a minimum.

 

[Bedford T]

I have never paid attention to the way the filter lies in the tank but I am beginning too. My br600 only had one filter till I copied the new design of two filters. I might look at if that can be improved on in the saws while it is on It's side. Or maybe hook up a fuel line to an IV bag feeding it fuel while you are pulling on a big slab. Wonder if that would work? They have a oiler already.

 

[Blairito]

I just got mine in the mail it seems the case halves have 2 different bearing designs one with a metal cage and the other with the plastic type
the bar stud side has the plastic type and the bearing will not spin freely, should i be concerned? will i have to replace the bearing or would they send me a new case half, they seem like they are machined differently as well.
also the cylinder on the intake side has a slit where it looks like the casting did not go well
any idea what they can do for me

 

[Ozhoo]

That's the way the bearings are. The one with the polyamide cage is a generic 6203 bearing. If the seal was driven in too far it would drag on the bearing. Yes you should be concerned... do not proceed till you figure out the problem. Post of picture of the seal side.

The casting flash is normal. You can grind it down if you want.

 

[Blairito]

That's the way the bearings are. The one with the polyamide cage is a generic 6203 bearing. If the seal was driven in too far it would drag on the bearing. Yes you should be concerned... do not proceed till you figure out the problem. Post of picture of the seal side.

The casting flash is normal. You can grind it down if you want.

its a void of metal not flashing
not sure if you can see the piston through the little slot in the top centre of the port

 

[Blairito]

my new phone camera doesn't seem to take up close pictures like my last

 

[emanaresi]

I think if they sent me that cylinder I would ask for a replacement. It does look like a defect.

 

[Bedford T]

69 2 photo at the roof you got a crack the seal look fine to me. Or maybe I am seeing it wrong with old eyes. This seal was set with the Stihl tool and it's the correct placement if that helps you compare it to your.