Porting a Chinese G621 Clone

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Zogger's guess sounds like the best explanation. Sometimes the fuel line is actually too long and the filter is held up in the wrong position. Just take a peak in the tank and see where it is - what to do about it will depend on what is happening.

I have not found mine to use too much fuel - it certainly uses more than my strato 40cc, but that is to be expected. That is a 25" bar on it.
 
Thanks for this thread -- it got me take a chance on getting one of these -- I have a lot of smaller saws that really just weren't up to some of these bigger old trees that died with Sandy. Thanks also Zogger for the advice! Ok -- so if the fuel line is too long (or too short) what can I do to adjust it -- change it? Do I need to take it apart? Do I need needle-nose pliers to get into the tank to make it longer? Any tips or advice -- or links to a thread on here would be very helpful.
 
Thanks for this thread -- it got me take a chance on getting one of these -- I have a lot of smaller saws that really just weren't up to some of these bigger old trees that died with Sandy. Thanks also Zogger for the advice! Ok -- so if the fuel line is too long (or too short) what can I do to adjust it -- change it? Do I need to take it apart? Do I need needle-nose pliers to get into the tank to make it longer? Any tips or advice -- or links to a thread on here would be very helpful.
I hope it works well for you - there may be various issues you'll need to deal with on it. For fuel line a pair of forceps is very useful, but you should be able to get to the line with needle nose pliers or even a wire with a hook bent onto the end.
 
Zogger's guess sounds like the best explanation. Sometimes the fuel line is actually too long and the filter is held up in the wrong position. Just take a peak in the tank and see where it is - what to do about it will depend on what is happening.

I have not found mine to use too much fuel - it certainly uses more than my strato 40cc, but that is to be expected. That is a 25" bar on it.

if the saw is using too much fuel, it may be due to a leaky cap. the plastic in theses saws is of marginal quality.
 
Something to be aware of - In addition to clearly being an 0.063" bar, the bar that comes with these also appears to be a D009 mount instead of the D176 required. They are very similar, the main difference being the 9mm slot vs. a 8mm slot in the D176. This makes it fit imprecisely in terms of vertical location and angle. I made up a quick spring steel spacer, which I'll probably make a port about, and it fits nicely now. Still, the bar & chain are the worst part of this deal.
 
Something to be aware of - In addition to clearly being an 0.063" bar, the bar that comes with these also appears to be a D009 mount instead of the D176 required. They are very similar, the main difference being the 9mm slot vs. a 8mm slot in the D176. This makes it fit imprecisely in terms of vertical location and angle. I made up a quick spring steel spacer, which I'll probably make a port about, and it fits nicely now. Still, the bar & chain are the worst part of this deal.

chris-

i' tries mounting my richmond bar on a husky but the slot is too small. i measured it with vernier calipers and it was a sloppy 8mm if my memory is correct. i did try running a husky 009 mount on the richmond but it wouldn't oil correctly. i'm thinking of making an adapter that would let me mount an 025 stihl bar. it would be easier to cook up than an adapter with .5mm shims. and there are some inexpensive 025 bars on the market.

question, have you solved the problem with the air cleaner? mine sucks fine saw dust from below the "silencer" plate right into the intake stack. i've thought about removing the silencer plate so that the filter and stack would have a deeper interface but i think the filter would have to be cleaned frequently with no barrier to block loose debris from the filter area. this afternoon i just gave up and sealed the silencer plate to the stack and the filter to both with silicone compound. i'll run it in wood tomorrow to see if it solved the problem.

regarding high fuel usage, i'm sure it's a leaky cap. i've had trouble with both mix and oil. the plastic has a lot of imperfections . some can be cleaned up by careful use of a sharp utility knife but the gaskets are crap. today i found that the fuel cap from a husky 575 is a good fit and will seat with adequate torque.

one other thing, throw out the tach when tuning. use the po' man's dyno, an 18" > round. start too rich and lean until you have good power. mine likes to run close to 12k rpm, not the 11k found in redmax specs.
 
chris-

i' tries mounting my richmond bar on a husky but the slot is too small. i measured it with vernier calipers and it was a sloppy 8mm if my memory is correct. i did try running a husky 009 mount on the richmond but it wouldn't oil correctly. i'm thinking of making an adapter that would let me mount an 025 stihl bar. it would be easier to cook up than an adapter with .5mm shims. and there are some inexpensive 025 bars on the market.

question, have you solved the problem with the air cleaner? mine sucks fine saw dust from below the "silencer" plate right into the intake stack. i've thought about removing the silencer plate so that the filter and stack would have a deeper interface but i think the filter would have to be cleaned frequently with no barrier to block loose debris from the filter area. this afternoon i just gave up and sealed the silencer plate to the stack and the filter to both with silicone compound. i'll run it in wood tomorrow to see if it solved the problem.

regarding high fuel usage, i'm sure it's a leaky cap. i've had trouble with both mix and oil. the plastic has a lot of imperfections . some can be cleaned up by careful use of a sharp utility knife but the gaskets are crap. today i found that the fuel cap from a husky 575 is a good fit and will seat with adequate torque.

one other thing, throw out the tach when tuning. use the po' man's dyno, an 18" > round. start too rich and lean until you have good power. mine likes to run close to 12k rpm, not the 11k found in redmax specs.
Well, I was actually guessing that it was a D009, but mine did measure a good 9mm on the slot. I made an adapter using the strip of stainless steel out of an old windshield wiper (yes, I always save those, they've been very useful). I heated it with a propane torch and bent it around a bolt:
IMG_0526_1.JPG
I would have made an S shape but the bar plate retaining bolt was in the way:
IMG_0527_1.JPG
It was just a little too thick so I thinned it with a flat file. It worked nicely:
IMG_0528_1.JPG
I was happy with it, and the chain cut great. Then I rocked it. Bad. The cutters are shorter now!

I'm getting some fines in around the filter mounting surface too. I made an aluminum tube to fit around the cover stud and inside the filter hole to serve as a positive stop, thinking the filter may have been getting distorted, and that helped a little (it is slightly sorter than the filter to keep pressure on the bottom seal). I tried smearing Yamabond on the surface, but that was not tough enough. I may just use grease next. It's not really bad actually, but I want to stop it.

I put a 20" bar on it today with a fresh loop of non-safety chisel, and the thing really rips. It revs much better than I thought it would. I do not have a tach, so I always tune by ear - my saw does have modified intake timing, so stock rpm numbers would not really be valid anyway.

I made my own seal for the oil tank out of some rubber stock I have around as the stock one was too small diameter to seal, and it works OK. I also found that a Ryobi 10532 gas cap would fit this oil tank. Luckily my fuel cap is sealing well.
 
25zni95.jpg
Too short => refill more often or replace with a new fuel line
Too long => cut shorter

7
Sure that sounds very simple -- but I am no expert -- the fuel line was in fact too long -- I pulled it out through fill hole --snipped it back as far as I could and then replaced the fuel filter -- but it is still too long -- and it does not flip back and forth freely -- so I ended up with it placed in the middle. I had a crew of really expert tree climbers and cutters yesterday and they had husqvarna saws (even a 24" one -- but they wanted to try this saw out -- sadly after just a few moments it died -- their take was that too much oil was getting to the muffler (whatever that means) -- and I think they really just wanted to use their $800 saws -- but at lunchtime they tinkered again with it -- couldn't stay away -- I am worried they might have flooded it -- but they are the pros -- at the end of they day I gave it a last try and it almost started...

Next weekend I might be on my own -- so any advice about how to adjust this from this point on -- and the best way to replace -- or to shorten the fuel line would be great. I must say that the workers saws were all far nicer -- the plastic was really top grade -- not my Richmond's flimsy type -- but they are full time pros and the best climbers I have ever seen. We took down 3 large old Maples and much of an Oak tree -- and would have been great to have had this saw was up and running too. Thanks for all the help.
 
I would not shorten the line any more until you can get it running and see how it works. I'll try to check mine and let you know where the H and L screws are set at - that should at least be a good starting point. Unfortunately, guys who use saws for a living are not necessarily knowledgeable about how to tune a saw, and they will not know this saw or probably the G621 it is based on. "Too much oil getting to the muffler" probably just means it is too rich.

I'm sure you will get it running and it will be useful for you, but I did try to be clear that these saws should be considered as a "kit", and may need disassembly, clean up and careful reassembly.
 
I would not shorten the line any more until you can get it running and see how it works. I'll try to check mine and let you know where the H and L screws are set at - that should at least be a good starting point. Unfortunately, guys who use saws for a living are not necessarily knowledgeable about how to tune a saw, and they will not know this saw or probably the G621 it is based on. "Too much oil getting to the muffler" probably just means it is too rich.

I'm sure you will get it running and it will be useful for you, but I did try to be clear that these saws should be considered as a "kit", and may need disassembly, clean up and careful reassembly.

Thanks! Yes, that you did say! ...but I really needed a 24" saw and I am on a 18" budget -- I will not use it often -- I wanted to rent one and there are none for rent in the NYC area (that I could find) almost bought a 22" from Home Depot (special order) -- I do think this will work out -- I have an acre and a half with lots of trees -- and this should (if it gets going) serve me well -- I might even listen to you and open it up at some point -- but that might be a while.
 
if your saw quit working on the job, i'd recommend that you inspect the air intake/filter system. mine is piss-poor. below is a picture taken after running about a third of a tank. bear in mind that this is after i calked the "silencer" plate below the filter and calked the filter to the silencer plate. i saw no evidence of my calked joints leaking. so, i'm thinking the the filter itself is passing debris thru its "clamshell" joints. there is actually significantly more debris inside the intake stack that there is on the outside of the filter. that means that little air is passing thru the filter medium but is entering thru leaky joints. this is a brand new filter. the saw arrived with a damaged filter assembly, due to misalignment of the filter cover to the carb. i have calked the clam shell together with more silicone compound and will do the silencer plate again and reassemble. its a pain.


1632_dust_air_intake-cv.JPG
 
Thanks! Yes, that you did say! ...but I really needed a 24" saw and I am on a 18" budget -- I will not use it often -- I wanted to rent one and there are none for rent in the NYC area (that I could find) almost bought a 22" from Home Depot (special order) -- I do think this will work out -- I have an acre and a half with lots of trees -- and this should (if it gets going) serve me well -- I might even listen to you and open it up at some point -- but that might be a while.
Ok, mine is set with the H at exactly 2T and the L at 1 T
 
if your saw quit working on the job, i'd recommend that you inspect the air intake/filter system. mine is piss-poor. below is a picture taken after running about a third of a tank. bear in mind that this is after i calked the "silencer" plate below the filter and calked the filter to the silencer plate. i saw no evidence of my calked joints leaking. so, i'm thinking the the filter itself is passing debris thru its "clamshell" joints. there is actually significantly more debris inside the intake stack that there is on the outside of the filter. that means that little air is passing thru the filter medium but is entering thru leaky joints. this is a brand new filter. the saw arrived with a damaged filter assembly, due to misalignment of the filter cover to the carb. i have calked the clam shell together with more silicone compound and will do the silencer plate again and reassemble. its a pain.


View attachment 344261
Eww! Mine is nowhere near that bad. I cleaned up the filter plastic with an X-acto and sealed the filter halves with Yamabond early on though. I've had other saws that let in as many fines as mine does.
 
if your saw quit working on the job, i'd recommend that you inspect the air intake/filter system. mine is piss-poor. below is a picture taken after running about a third of a tank. bear in mind that this is after i calked the "silencer" plate below the filter and calked the filter to the silencer plate. i saw no evidence of my calked joints leaking. so, i'm thinking the the filter itself is passing debris thru its "clamshell" joints. there is actually significantly more debris inside the intake stack that there is on the outside of the filter. that means that little air is passing thru the filter medium but is entering thru leaky joints. this is a brand new filter. the saw arrived with a damaged filter assembly, due to misalignment of the filter cover to the carb. i have calked the clam shell together with more silicone compound and will do the silencer plate again and reassemble. its a pain.


View attachment 344261

Surprisingly my G621 Richmond/Poormond clone's air filter has yet to be letting any saw dust get through into the carb -- but I have only cut one 18" piece of maple with it (the only cut ever) -- and the saw dust all ended up in one little place on the filter (but on the correct side of the air filter) -- it was all in a round circle about the size of a quarter -- is that normal? The rest of the filter looked very clean. If I get it going I will keep an eye -- but it all seems fairly tight from the factory -- and as is obvious it is the least of my current troubles..
 
Ok, mine is set with the H at exactly 2T and the L at 1 T

Thanks very much Chris! (and everyone else too) Chris -- hate to ask -- but I don't know what 2T and 1T really mean -- any chance I can get a picture -- or just some "Chainsaw for Dummies" description? Again -- I don't have my chainsaw here it is down on that property still. Also any threads that you can recommend on how to fine tune this carb?

To add insult to injury -- here is a link to the RedMax G621 manual online (click below)


http://www.redmax.com/ddoc/RMXO/RMXO2007_USen/RMXO2007_USen_G621AVS_.pdf


dz6t94.jpg


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ALSO

In this manual is a picture of a hook removing the fuel filter -- my fuel line is not much longer than that... but it is stuck in the middle so maybe a hair more needs to be taken -- or perhaps the line is too hard and inflexible...
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11bngpc.jpg
 
Thanks very much Chris! (and everyone else too) Chris -- hate to ask -- but any chance I can get a picture? Also any threads that you can recommend on how to fine tune this carb?

dz6t94.jpg


To add insult to injury -- here is a link to the RedMax G621 manual online (click below)

http://www.redmax.com/ddoc/RMXO/RMXO2007_USen/RMXO2007_USen_G621AVS_.pdf

In there is a picture of a hook removing the fuel filter -- my fuel line is not much longer than that... but it is stuck in the middle so maybe a hair more needs to be taken -- or perhaps the line is too hard and inflexible...

11bngpc.jpg
The first thing to do is set the L (the H doesn't do anything at idle, but set it at 1-1/2 turns). But to do the you will need to get it to fire. There are no limiters on these. I'd set the L at maybe 1-1/4 turns from gently seated, maybe clean the plug and try to get it to fire.

Once it fires then you want the L set just on the rich side of max idle speed ( rich is counter clockwise).

If you get it to idle then you want the H set so you can just hear a misfire when you lift, but but smooths out under load.
 
The first thing to do is set the L (the H doesn't do anything at idle, but set it at 1-1/2 turns). But to do the you will need to get it to fire. There are no limiters on these. I'd set the L at maybe 1-1/4 turns from gently seated, maybe clean the plug and try to get it to fire.

Once it fires then you want the L set just on the rich side of max idle speed ( rich is counter clockwise).

If you get it to idle then you want the H set so you can just hear a misfire when you lift, but but smooths out under load.

Very kind of you Chris -- Cheers! OK...one last question -- is the fuel line used in these clones any stiffer / less flexible than in most other branded saws? Will it soften up with fuel -- or is it likely just that mine is still a little too long -- it stays stuck in the middle when placed there.
 
Very kind of you Chris -- Cheers! OK...one last question -- is the fuel line used in these clones any stiffer / less flexible than in most other branded saws? Will it soften up with fuel -- or is it likely just that mine is still a little too long -- it stays stuck in the middle when placed there.
I have not noticed that it is appreciably different from other line I've worked with. With fuel in there and the saw moving around it may not be as stuck as it seems.
 
BTW - I looked at the line in my tank, and the filter is sitting towards the fill cap. I have not had any issues running it, but then I seldom hold it starter side down either (I find it uncomfortable).
 
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