Porting a Chinese G621 Clone

[Chris-PA]

It sounds like it is lean in the video, but it didn't when I tuned it shortly before. Of course it is pulling a 24" bar in pretty hard wood so the load was never very light. A shot with a 20" bar later:

 

[BDM53ENT]

I'm just going to make a fire down there or it will be hell to clean up.

LOL! I guess thats one way of cleaning it up in a hurry. Good to see shes alive and kicking!

 

[Chris-PA]

Well I got to trim up the stump and then the rain started, so I retreated to the barn to go over some chains. I took another look at the bar and chain that came with it - it's been bugging me because while the fit is sloppy, I have other worn bars that don't cut circles. I looked more closely and the chain and saw that I had clearly hit something with the side plate. I'm surprised I did not see it before. I had trouble getting a good shot:

That ring around the gullet is actually deformed inward. So this is why it cut in circles, or at least I'm betting it is. I got out the cheap grinder and cut them back, and then finished with a file and set the depth gauges. No I have to wait to see how it works. I will still buy a loop of 0.063" for it but hope to be able to use this one.

 

[heyduke]

Well I got to trim up the stump and then the rain started, so I retreated to the barn to go over some chains. I took another look at the bar and chain that came with it - it's been bugging me because while the fit is sloppy, I have other worn bars that don't cut circles. I looked more closely and the chain and saw that I had clearly hit something with the side plate. I'm surprised I did not see it before. I had trouble getting a good shot:
View attachment 341840
That ring around the gullet is actually deformed inward. So this is why it cut in circles, or at least I'm betting it is. I got out the cheap grinder and cut them back, and then finished with a file and set the depth gauges. No I have to wait to see how it works. I will still buy a loop of 0.063" for it but hope to be able to use this one.

the chain sent with mine was .058 while the bar was .063. the chain was ground with a 5/32 inch radius which made it self feed nicely but cut slowly. it threw a mix of fat chips and corn meal that got all over everything. i found a suitable oregon d157 24" bar in my pile of stuff and made up an 82 dl chain out of carlton. it works much better.

 

[Chris-PA]

Not bad. The MS4018PAV sounds healthier.

They are quite different - the MS4018 likes to rev, but then it is not pulling a mostly buried full kerf 24" bar either, and has the benefit of much more advanced porting and a large air intake.

I had read that the G621's did not like to rev much, so I was happy that it did not seem sluggish. I may still look for a bigger carb for it.

 

[weimedog]

Someday I must pan back a bit so you can see the absolute crap hole that I work in! There is probably a pile of junk from every project I've ever worked on, with half a dozen more on top of it. When I need to get to the table saw it's like an archaeological dig. My desk at work is just the same - they gave up trying to get me to clean it up years ago.

BUT...

I am a little picky about how things fit together. This one is not too bad now. If it holds up I may order some small bits - A/V covers and air filter cover screw, etc. - from RedMax just so it looks a little nicer. But the air filter is like $37 ( ) so I'll be making this one work!

"Creative Minds Are Seldom Tidy" - My mothers saying.....and gave a little sign to my OCD wife with that on it

 

[weimedog]

Yeah that bit of marketing fluff has been around a while. The saw they tested is not a copy of any Stihl, it is clearly a RedMax G5000 clone. I suspect the original G5000 would have performed the same. Does that make it a bad saw?

Do the tests represent what you would do with a saw? If those kinds of forces were placed on the saw, what would happen to the operator? Did the added strength needed to pass those tests increase the price or weight, and would you make that tradeoff if it did?

As an engineer, you know design & production is slave to marketing and sales! That's a marketing and sales generated flick...

 

[weimedog]

I was drawing out the diagram of the port timing and thought I'd stick it in here:
View attachment 337264

Not bad numbers! Certainly better than my Huztl! That might be a fun comparison....you 62cc Chinese saw and my Huztl Chinese build, which BTW cuts quite well.

 

[weimedog]

Interesting and informative Chris, and thanks for sharing a closer look. But I really gotta take a couple shots at this saw. (not at you)

Guys are talking about the timing numbers here, but I'm thinking about the financial numbers. $210 to the door is really not that great of a deal for something of such dubious origin. And you've already identified so many flaws in it's brief stay that words like crap and junk are not unjustified. Right on the heals of that $210 are some costs that the typical buyer would quickly face. The hokey bar and chain will not last long, assuming the saw runs long enough to wear them out. Figure another $50 right there. The top cover wouldn't stay on, the air filter won't seal, the saw stopped oiling, the carb is suspect, and the bar and chain are borderline useless. And all for just $210. Call now, operators are standing by! Did someone say junk? Where would Joe Consumer go to get that torn oil line? The average person would not be able, or even inclined to do all the alterations that you did to make this saw somewhat usable. They would feel totally screwed and that's exactly how they should feel. The average yard sale saw wouldn't have that many issues.

All that talk of trying different, (and real), carbs is interesting from hobby/curiosity standpoint, but again, $210 for the "raw materials" for this project seems out of line for what you get. There are so many used saws that could be had for much less money, that would yield much better results.

Yep...he....... LOL spoken like a reputable dealer.... BUT the 543 has been shipped!

 

[weimedog]

Simple - a 170 is a really cheaply made plastic clamshell, and chainsaws don't really cost that much to make which means that they can sell the low end ones cheap if they want to. They'll make their money on the expensive ones. And a 170 isn't a 62cc saw either.

Then again a 50cc strato engined Poulan Pro will cost you about the same as that 170 - how come that Stihl costs so much?

I bought a Hyundai Accent in 1999, cheapest car available at the time. Leather wheel and shifter, dead peddle, sunroof, alloys, fog lights, A/C, great adjustable seat. Best car I ever owned, dead solid reliable, easy to service, fun to drive and never gets less then 30mpg. Still drive it every day.

Oh, and you do know that Daewoo designs all of GM's small cars don't you?

Now your beginning to sound like someone who works at Mack Truck...

 

[weimedog]

If you've got 60" cedars then you'd be one of the few that could use an 090 for the purpose it was intended.

That's quite an investment. Even with this big $210 expenditure of disposable cash which you so obviously disapprove of (note that I do not need your approval), my saws in total are worth a tiny fraction of what you've spent. Seems quite curious to be chastised by some guy who's spent what you have. Every one of my saws is considered junk, all but 2 were used and broken. Every one runs perfectly. We heat exclusively with wood, and the house is warm and cozy, and next year some of that wood will be cut by this saw. There is really no need to feel threatened by my cheap saw, it's not going to devalue your collection.


Oh, I can read. You've made your point quite clear and are nowhere near as subtle as you believe.

To those haters....bring it on! I put $250 into that Chinese Huztl build I did this winter. Bet you can't find a $400 dollar new saw option in the same league in terms of power and capability! And have to say from the pictures so far, the Huztl quality seems better than what your pics are showing. Point being not all Chi-Com stuff is junk, and as time goes on expect it to get better. We really need a Mini GTG to pick through this stuff....could be fun.

Can do a youTube video and really fire up the doubters, with the bars in full 24in engagement on hard maple with a rooster tail of chips!

 

[weimedog]

I get the purpose of this thread and again, I thank you. I guess I just can't wrap my head around why anyone would want to spend $200 on a 62cc saw, which has to be torn down and worked on before they're even run. You believe the saw you described, with the questionable bar and chain and poor fitting plastics and factory defective filter is really worth $200? If you didn't have the money and were in dire need of a 60cc saw, you could do a whole lot better with a used saw. And no, I don't need to actually hold or run that Chi-com POS to know that. Now, if you could get that same saw for around $40, and get someone to throw in a real bar and chain, that might be different.

My guess is if the thing is still running after it's first tank, and if the chain hasn't come apart and injured someone, you'll be spending at least another $60-$65 on a GOOD bar and chain. Making your initial investment around $275 for a tool, that according to your postings, doesn't seem very capable, unless of course, you only intended to start it up a couple of times in the garage. Again, If it was only $40, or so, different story.

BTW, the AM parts I have had to clean up were being put on "dead" saws, not new ones like yours.

I get the point....saw puzzles. Mechanical puzzles. Some folks do things like RC cars, other restore old motorcycles, the more well heeled; airplanes! I my case "saw puzzles" save me around $4000 a year in oil! My wife finally gets it. PLUS especially for an engineer, after a while the SOSDD syndrome hits, and there have to be other ways to channel that creative urge..... back to the mechanical hobby's.

(SOSDD= Same Old Chit Different Day)

 

[weimedog]

Yeah, a lot of the old guys left the forum because of this type of crap. I don't remember guys like Timberwolf ever working on a Chinese saw, but he still took the same kind of ignorant BS whether he was working on a Stihl or Husky. I can understand why he and others left. - A bloke takes the time and effort to try to expand the information base, and then you get morons with 'adequacy issues' that try and down grade it with pathetic snipes from their keyboard.

Thanks Chris for your contribution to the forum, it makes up for some of the others that are incapable of contributing.

Bingo and well said.

 

[Chris-PA]

I get the point....saw puzzles. Mechanical puzzles. Some folks do things like RC cars, other restore old motorcycles, the more well heeled; airplanes! I my case "saw puzzles" save me around $4000 a year in oil! My wife finally gets it. PLUS especially for an engineer, after a while the SOSDD syndrome hits, and there have to be other ways to channel that creative urge..... back to the mechanical hobby's.

(SOSDD= Same Old Chit Different Day)

Yup, you gotta do something different sometimes!

 

[Chris-PA]

So there was a brief break in the torrential rains this morning, enough for me to go out and try a cut with the repaired chain. It cut straight and true, so I was happy. Then I looked at the side plates of the cutters and found the damage was back! I had not hit anything, and it was only one cut. The damage is on the cutters on the inside, so I was suspicious it was hitting something. The wear pattern here is a clue:

You can see how the cutters have been dragging on the drive sprocket. The question was why? Ultimately I decided it was due to three things:

1. The sloppy bar groove/driver fit allowed the cutters to move around too much.
2. There was not enough clearance to the face of the drive sprocket
3. It turned out the left hand threaded nut that holds the sprocket on was threaded at an angle, so that when it was tightened down the inner surface was at an angle. That allowed the washer to sit at an angle, and the drive rim too.

So I made a shim out of 0.032" fiberglass to try spacing out the drive rim:

I will look for a way to make one out of better material, but it should hold up for a bit. There is still more than 0.040" clearance. Then I filed the inner surface of the nut to reduce the angle (I don't have any other left hand nuts at the moment). With all of that it appears to have good clearance between the inner cutters and the drive sprocket now:


Of course I had to work over the chain again. It is possible that the downpours have stopped for a bit, so I may go try it out.

EDIT: That seems to have fixed it. The chain cut quite nicely actually. Before I order a 0.063" chain I want to see how this one works. I'm trying to decide whether to get skip or full comp, and this is full comp semi chisel on a 25" bar.

 

[heyduke]

So there was a brief break in the torrential rains this morning, enough for me to go out and try a cut with the repaired chain. It cut straight and true, so I was happy. Then I looked at the side plates of the cutters and found the damage was back! I had not hit anything, and it was only one cut. The damage is on the cutters on the inside, so I was suspicious it was hitting something. The wear pattern here is a clue:
View attachment 342030
You can see how the cutters have been dragging on the drive sprocket. The question was why? Ultimately I decided it was due to three things:

1. The sloppy bar groove/driver fit allowed the cutters to move around too much.
2. There was not enough clearance to the face of the drive sprocket
3. It turned out the left hand threaded nut that holds the sprocket on was threaded at an angle, so that when it was tightened down the inner surface was at an angle. That allowed the washer to sit at an angle, and the drive rim too.

So I made a shim out of 0.032" fiberglass to try spacing out the drive rim:
View attachment 342032
I will look for a way to make one out of better material, but it should hold up for a bit. There is still more than 0.040" clearance. Then I filed the inner surface of the nut to reduce the angle (I don't have any other left hand nuts at the moment). With all of that it appears to have good clearance between the inner cutters and the drive sprocket now:
View attachment 342033

Of course I had to work over the chain again. It is possible that the downpours have stopped for a bit, so I may go try it out.

EDIT: That seems to have fixed it. The chain cut quite nicely actually. Before I order a 0.063" chain I want to see how this one works. I'm trying to decide whether to get skip or full comp, and this is full comp semi chisel on a 25" bar.

i wonder how hard it would be to fine a new nut. would that solve the problem?

 

[Chris-PA]

i wonder how hard it would be to fine a new nut. would that solve the problem?

Not hard at all - I ordered a couple. The one I tweaked seems to work fine now though, so I will save it for the next time I do maintenance. I'm looking forward to running it more now with this bar and chain combination, as I liked how it cut for the short amount of time I got to put on it yesterday.

 

[HarveyCat]

Thanks for this thread -- and for this great website! Ok, so I ordered one of these 24" Clones for $209 delivered -- it works great -- my only real problem is that when cutting with this chainsaw on its one side (with a half tank of gas) it just dies straight away -- but the funny thing is -- it is fine when turned on its other side. I have a lot to cut this weekend (still some Sandy trees) -- and advice would really help -- I am going to try it with a full tank of gas in the morning and see if that works. Oh and by the way -- this thing does use a lot of gas -- I never ran a 62cc is that normal? Runs great though!

I saw this thread -- with some good things to test for...
http://www.arboristsite.com/community/threads/chainsaw-stalls-when-turned-sideways.123933/

 

[zogger]

Thanks for this thread -- and for this great website! Ok, so I ordered one of these 24" Clones for $209 delivered -- it works great -- my only real problem is that when cutting with this chainsaw on its one side (with a half tank of gas) it just dies straight away -- but the funny thing is -- it is fine when turned on its other side. I have a lot to cut this weekend (still some Sandy trees) -- and advice would really help -- I am going to try it with a full tank of gas in the morning and see if that works. Oh and by the way -- this thing does use a lot of gas -- I never ran a 62cc is that normal? Runs great though!

I saw this thread -- with some good things to test for...
http://www.arboristsite.com/community/threads/chainsaw-stalls-when-turned-sideways.123933/

Did you check the fuel line and filter when it was empty? Does it fall and go to the bottom easily whichever way you hold the saw?

 

[HarveyCat]

Thanks for the advice! I didn't check to see if the fuel line & filter moved freely in both directions (without fuel) -- but I will check it first thing in the morning -- it does run great when it is either straight up -- or on one of its two sides.... just not the other side. If I do find that it only falls one of the 2 ways -- what is the fix? I did get a new universal fuel line (see link) - but not really sure it will work for this saw.
http://www.homedepot.com/p/Power-Care-1-ft-Universal-Fuel-Line-Kit-490-240-H010/203381015