Huztl MS 440 Initial Impressions, and Build

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I whipped this degree wheel up this morning and got the chuck at harbor freight. seemed to work fairly well. Also here is the spring that does not work. If anyone can elaborate on those port numbers that would be great.
 

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After thinking about it some more, there's no way the cylinder walls from base to squish band are 0.072 inches different front side the back side. I will post the real numbers when I get home.

I guess I forgot how bad my memory is.
Huztl 50mm cylinder
-distance from base to squish band intake side = 72.22mm
-distance from base to squish band exhaust side = 72.40mm
That's about 0.007 inch.

OEM 50mm cylinder
71.60mm intake side base to squish band
71.95mm exhaust side base to squish base
That's about 0.014 inch.
 
Your intake opening makes no sense, but if the duration is correct, then u are at 75.

I thought your loose squish was sans base gasket. Roof flashing is only .010 thick and may bring you to 22. You'll need sealant on both sides.
 
The numbers you are posting look great.

I bet if you go with a custom .010 base gasket, you'll be at 102/118/76. Near perfect numbers.

The ports don't move symmetrically because piston speed varies during stroke. There's nearly no movement at tdc or bdc, but more in the center of the stroke.

Sounds like you've got a runner there.

I'd still go Meteor. I get your point, and the point of the thread. But no reason not to have a little insurance. Plus, the supplied piston likely won't be consistent anyway. So if yours lasts, someone else's may not.

Obviously your call. Thanks for doing this thread. It's interesting.
 
I whipped this degree wheel up this morning and got the chuck at harbor freight. seemed to work fairly well. Also here is the spring that does not work. If anyone can elaborate on those port numbers that would be great.
Photos of my 440 built with brake spring installed.
 

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Those are different springs. Eb they pulled the wrong part and included in in your kit.
 
The numbers you are posting look great.

I bet if you go with a custom .010 base gasket, you'll be at 102/118/76. Near perfect numbers.

The ports don't move symmetrically because piston speed varies during stroke. There's nearly no movement at tdc or bdc, but more in the center of the stroke.

Sounds like you've got a runner there.

I'd still go Meteor. I get your point, and the point of the thread. But no reason not to have a little insurance. Plus, the supplied piston likely won't be consistent anyway. So if yours lasts, someone else's may not.

Obviously your call. Thanks for doing this thread. It's interesting.

Thank you for the response i thought by cutting the base i trashed the cylinder. Yes i must have read the degree wheel wrong when finding the intake i will recheck tonight.

As for the spring i just sent an email so hopefully i will get Huztl to answer back, if not i will try and find a used one or just get oem, can't be that expensive.

Glad to hear at least someone have faith in the port timing. Once again i am just using this as a base and in a few weeks another cylinder should arrive and the performance modifications will be in full swing and i will be able to really test the saw.
Thanks again n for the insight, i have never dealt or even though about port timing until about last night:) .
 
The numbers you are posting look great.

I bet if you go with a custom .010 base gasket, you'll be at 102/118/76. Near perfect numbers.

The ports don't move symmetrically because piston speed varies during stroke. There's nearly no movement at tdc or bdc, but more in the center of the stroke.

Sounds like you've got a runner there.

I'd still go Meteor. I get your point, and the point of the thread. But no reason not to have a little insurance. Plus, the supplied piston likely won't be consistent anyway. So if yours lasts, someone else's may not.

Obviously your call. Thanks for doing this thread. It's interesting.
I could just shave .010 off top of piston, or off the base of the cylinder. What you think.
 
My bad i don't know what i was thinking, taking it off the piston would be working back words.
 
I am going to build it up on Monday when the new piston retainers get in and test compression. If low then i might take of .010 off the base of the cylinder to get me to the port numbers. If not i will just leave it.
 
Stock timing is all over the place, even with OEM jugs.

Not sure why you didn't have the machinist take a bit more off the base to get squish near 20-25.

How thick did your base wind up?

Until you put a degree wheel on it, you really have no clue where your ports are at.

Torqusoft has a pretty good program that converts measurements to degrees. It's fairly accurate also.

Good numbers for your saw are around 102 exhaust roof opening, 120-122 transfer roof opening and 76 intake floor opening. You can modify the intake opening by relieving the piston skirt if need be.

Besides not being true perpendicularly and bad squish/chamfering, AM jugs are notorious for exhaust roofs that are too flat and wacky timing numbers.

The one thing I would add to your build is a Meteor piston with the pins and clips. They're under $50 and are darn good pistons that come with caber rings. That's the one area I see that I just wouldn't skimp on. You've come this far.
I made a Excel spreadsheet that converts piston distance from squish band to degrees of crank rotation. It works for any saw. Enter stroke, connecting rod length, squish. It has a column that shows the distance from the squish band and another column that shows the rotation degrees. It is as accurate as you can measure the port differences from the squish. It has other information that is interesting like displacement, rate of displacement and other useless stuff. I have one setup for a 660 and the 440. I do need an actual connecting rod length for a 440.

I don't know how to post an Excel file but I if some tells me how I will post it.
 
yes that would be interesting to play with, i don't know the connecting rod length, hopefully someone does.
 
Yep, that's not what mine looks like, Eb's looks like it would work, but the anchor hook (large hook) on his is rotated to make it unusable. My large hook is completely different - my large hook is off to one side of the spring coils.

Sorry I don't have a picture - I'll try to explain. If you held your spring by the small hook, and let it dangle large hook down, and you dropped a pen through the spring coils from the small hook end, the large hook would catch the pen, because the large hook is in the same plane as the center axis of the spring coils. If I held my spring the same way (large hook down) and dropped a pen through the coils, the would fall to the floor, because my hook is off to one side. My hook is in the same plane as the outer edge of the spring coils.

It appears that there are several spring versions in these kits.

Photos of my 440 built with brake spring installed.
 
I might need a new carb too. The choke plate return spring on mine is too weak to reliably open the choke once the master control lever is moved off "full choke".
 
I might need a new carb too. The choke plate return spring on mine is too weak to reliably open the choke once the master control lever is moved off "full choke".

Try holding the choke closed and loosen the butterfly screw then retighten. Might be binding
 
5 out of 8 of mine for the 660 have needed the butteryfly reset. Really simple task. I also open up the carb diaphragm cover and make sure that the metering valve moves freely, I've had a couple that felt stuck till I pressed the metering lever.
 
Here my reviews of quality and fitment. I will be rating them on school grading scale
a+ compares to Stihl OEM
a being like OEM
You get the point, the grades include fit and finish as well as sturdiness in the hand. Obviously, i have not even ran the saw yet nor have i put any of these parts tot he test but depending on how they feel you can get a pretty good idea, again just initial impressions.

The Recoil Starter assembly,
B+
I find it feels sturdy and really doesn't feel that different from an OEM assembly, the rope action feels smooth and precise and there isn't a lot of play.
 

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