Makita Dolmar 6421 problem

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I made a post earlier but took it down. It sounds like you want a bigger saw than what you already have. But if you just want a backup saw that parts are easier to find on consider the Echo 590 (it isn't a gas hog either). They can be had cheap new or lightly used because people get them for one job or in case of an emergency - lose interest and sell them.

I had a 58cc Shindaiwa and was impressed with it - very reliable, nothing fancy but well made - but a parts nightmare. I figured the Echos would be similar and they are. Parts are easy with these Echos. I found a couple new ones for $300 each. This saw isn't as good as a pro saw, but it is better than a farm saw.

Looking on Craigslist I see a Timberwolf for $250, "... used 3 times, like new....... " Maybe I should call one of my brothers in Longview, Washington (Ranier is right across the Columbia River on the Oregon side). They go over to the Oregon side through Ranier to launch their boat to go salmon fishing. ;) - No, I'm good, no more saws. That is a lot of saw for the price. Look at that bar - it looks new. My bars have no paint on them anymore!
https://portland.craigslist.org/clk/grd/d/rainier-echo-590-timberwolf-chainsaw/7623745377.html

I was out 2 days ago with the Echo 590 and the Dolkita 7900 working on some Lodgepole pine. The Echo held its own with the bigger saw. I'm sure the story would be different in something like Locust or Oak, though.

Dang it, now you have me looking at the CS-590 echo. It's actually a mag case like a pro saw. I might just call that portland guy. Hope he didn't straight gas it.

I need to go to oregon to pick up some freon for my daughter's car. It's outlawed in WA.
 
Good luck. The ad is over 20 days old - it is probably already sold. If not, the seller is probably anxious to sell.
 
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90cc g600 is in a different class than the 60 cc saws. If it’s a backup saw for me it’s going to wear a 32 or 36” lightweight bar. If I got echo or Stihl that would be my primary saw. And I don’t see the 560 or the 262 pulling a full 32”+ cut.

If you want a backup saw that can pull a 36” cut for under 600$ I don’t see another choice.
Up the price to 800$ is there anything available now? Don’t know of any 70cc or larger saws that could do it.

I have the biggest loudest chainsaw on the block. To be honest it needs a new home. My milling days are probably over. My battery saw is good enough back up for anything I’d need to cut. I have friends that would gladly let me barrow it back if I needed it again. But it’s still in my shed. I smile at it every time I see it. I have not stated it in a year. But it’s there if I need it. Hurricane season is here.
 
Used blue “surface insensitive” lock tite
Get that thing hot and put a wrench on the muffler bolts...I bet you'll find the blue Loctite is doing nothing for you...gotta use the high temp stuff to hold those bolts. Blue is only good for something like 300* F.
For this I would use Loctite 246, which is rated to 450* (still barely adequate IMO)
 
Get that thing hot and put a wrench on the muffler bolts...I bet you'll find the blue Loctite is doing nothing for you...gotta use the high temp stuff to hold those bolts. Blue is only good for something like 300* F.
For this I would use Loctite 246, which is rated to 450* (still barely adequate IMO)
I did a lot (for me) of reading at various chainsaw forums and the consensus was to not use red loctite. Most said blue, and some said none. There certainly wasn’t any thread locker on there from the factory.
 
I did a lot (for me) of reading at various chainsaw forums and the consensus was to not use red loctite. Most said blue, and some said none. There certainly wasn’t any thread locker on there from the factory.
246 is blue...just the high temp version.
Loctite makes a TON of different products, most people have NO clue how many!
There certainly wasn’t any thread locker on there from the factory.
I wonder why it fell apart? ::-)
 
246 is blue...just the high temp version.
Loctite makes a TON of different products, most people have NO clue how many!

I wonder why it fell apart? ::-)
My bottle just says “blue”. But in the part number is a 243. Oh well, something is better than nothing.

C21E942D-C35B-4F9C-89D5-390F77CDF7AE.jpeg
 
Good luck. The ad is over 20 days old - it is probably already sold. If not, the seller is probably anxious to sell.

You were right. Crickets from the seller. My primary is working now but the wood is all processed for 24/25 and maybe farther so no big need for another saw right this minute. I'll keep looking but the 660 seems to be the most logical.
 
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Ya, a big saw 90+cc would make short work of big Doug Fir logs. She gives her opinion on the G660 clone - she has 2 commercial customers who run the G660 saws - she sounds pretty positive.
 
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Interesting video, thanks for posting. What caught my attention is when she mentions the bar length and the g660 pulling 28” bar and it felt nothing like the ms661 pulling the same 28” bar. I thought 90cc is 90cc. Is there more to power output than that? Sharp chain of course.
 
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It ain't all about the cc's and the HP's. Torque (and torque curve) and rpms also plays a part in how any engine does its work.
I have never had a clone machine in my hands so I have no dog in this hunt. One thing I will say is that stihl doesnt require 25:1 fuel mix. Something is different.
 
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It ain't all about the cc's and the HP's. Torque (and torque curve) and rpms also plays a part in how any engine does its work.
I have never had a clone machine in my hands so I have no dog in this hunt. One thing I will say is that stihl doesnt require 25:1 fuel mix. Something is different.
Good point about the fuel mix. I was surprised she did not mention it.
 
The ports on the clone saws are often not as good as OE. But I think the 660 clones are the best of the lot. The clone pistons have thicker walls than OE and are heavier, so the saw will vibrate more.

I think they recommend 25:1 oil ratio because they're assuming low quality oil. If you use good synthetic two stroke oil a lighter ratio would be fine.
 
Not all 90cc are created equal
Thats why "Porters"get better power out of a stock saw.
I run 32:1 in everything that takes mix.Insurance oil is cheap.
 
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I think they recommend 25:1 oil ratio because they're assuming low quality oil. If you use good synthetic two stroke oil a lighter ratio would be fine.
That and they know their QC is crap, so add extra oil to give 'er a fighting chance.
An example of poor QC (just one of many) when I built a 660 clone a few years back I had to clearance the piston skirt as it hit the crank at BDC! I checked and hand fit every single piece of it, replaced some parts with OEM Stihl right off the bat...so far so good, the only issue has been a broken pull rope (base gasket delete, so higher compression) and had to go back and shim the chain tensioner gears so they would mesh properly. Oh, and the cylinder bolts tried to loosen up on me during break in too...fortunately someone in the vicinity of where I was cutting heard it lean out when I was coming out of the cut and mentioned to check things over...tightened the crap outta the bolts, adjusted the carb, been fine since...and it pulls a 32" bar just fine.
I run mine on 32:1 semi synthetic.
 
Not all 90cc are created equal
Thats why "Porters"get better power out of a stock saw.
I run 32:1 in everything that takes mix.Insurance oil is cheap.
I run 32:1 on the mill. And have a digital tach to tune. Stock from the factory my g600 was almost 13k rpm WOT. I didn’t touch it until I added my 54” bar and had a tach. I tried tuning by ear and had my ryobi over 15k.
 
I run 32:1 for the g660 too, as recommended here. One thing i did not do ( not very good at it by ear or tach) was retune it. Seems to be running fine. My 261c on the other hand😳. Sometimes it sounds sooo lean… it screams! But it has autotune right?
 
Cut a few cords of big 24" maple with the dolmar, 28" bar, skip chain, in hot weather. Always "hot laps" as I use a mingo marker to mark a whole log and then just go cut after cut with no rest. After that crazy hot cat muffler cooled down I checked for looseness and none was detected. Next day, still tight. So I'm happy and consider this fixed. Thanks for the help.

Oh and I still want an 066 clone. I should have over 21 cords of wood CSS and will plan on selling some to justify funding a backup saw.
 
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Cut a few cords of big 24" maple with the dolmar, 28" bar, skip chain, in hot weather. Always "hot laps" as I use a mingo marker to mark a whole log and then just go cut after cut with no rest. After that crazy hot cat muffler cooled down I checked for looseness and none was detected. Next day, still tight. So I'm happy and consider this fixed. Thanks for the help.

Oh and I still want an 066 clone. I should have over 21 cords of wood CSS and will plan on selling some to justify funding a backup saw.
won’t take but a couple cords to pay off the clone. I gave keeping up with current quality of the clones. The OPE forum was toxic. If you get one, get a tach. But honestly I’d sell a couple more cords to get a lite pro 50cc class saw. And some more to get it ported.
 
won’t take but a couple cords to pay off the clone. I gave keeping up with current quality of the clones. The OPE forum was toxic. If you get one, get a tach. But honestly I’d sell a couple more cords to get a lite pro 50cc class saw. And some more to get it ported.

At this point in my life I want a larger engine/saw since I'm not cutting branches but bucking rounds and cut speed is very important. I would not get it ported but want to start with a saw big enough to not need porting to make gobbs of power. The 64cc dolmar is okay but for a similar weight a 92 cc saw ought to do the job faster won't it?
 
80cc- 79xx dolmar is a little faster with the same bar but not by enough to count. dif is i can hang a 36" bar on it and sail through bigger diameter stuff. other than the jug and piston its the same saw ( and weight) these are stock no muf mods or anything else at present. getting a muffler mod ( get rid of cat) on the 21 and retuning will wake it up a fair amount. Thing is there are big bore kits for the 79xx and 64xx that take them to just about 90cc, lot cheaper than another saw, course who doesn't want another saw? the problem now is that with Makita and Husky pulling the plug on gas powered items, all you are left with is Stilh, or clones of either Husky or Stilh in the 90cc class. Imo, this shift to electric is highly over rated- the juice packs are not up to meeting a gasser head on. At the cost of batteries not a good deal. You can fix a gasser, 9 times out of ten can't on a electric, or the cost exceeds value. Mega dollar throw away units. Just like the current EV vehicles. Those have been around long enough now that this is just coming to light. You can argue the point but I am here now and likey won't be 20 years from now when the dust settles and I generally get more than 20 years from my trucks, mowers and such. I have an Ford 8N tractor here in shop about 80 years old. Still doing the jobs it was built for. Course if the powers that be decide to make fuel unobtainable or more ridiculously priced then we are at now all bets are off .
 
I haven't been in a Home Depot for a while. I was there a few days ago. Of course I walked the aisle with the chainsaws (maybe something would be on sale). Anyways, I noticed the Echo gas chainsaws were no longer on display but were still for sale in boxes.

I also noticed an electric chainsaw - it was about twice as big as the last electric saw I had seen! It looked like a regular sized chainsaw - technology is moving fast. Blades, it is only a matter of time before electric chainsaws take over and gas saws go the way of the dinosaurs.:confused:
 
80cc- 79xx dolmar is a little faster with the same bar but not by enough to count. dif is i can hang a 36" bar on it and sail through bigger diameter stuff. other than the jug and piston its the same saw ( and weight) these are stock no muf mods or anything else at present. getting a muffler mod ( get rid of cat) on the 21 and retuning will wake it up a fair amount. Thing is there are big bore kits for the 79xx and 64xx that take them to just about 90cc, lot cheaper than another saw, course who doesn't want another saw? the problem now is that with Makita and Husky pulling the plug on gas powered items, all you are left with is Stilh, or clones of either Husky or Stilh in the 90cc class. Imo, this shift to electric is highly over rated- the juice packs are not up to meeting a gasser head on. At the cost of batteries not a good deal. You can fix a gasser, 9 times out of ten can't on a electric, or the cost exceeds value. Mega dollar throw away units. Just like the current EV vehicles. Those have been around long enough now that this is just coming to light. You can argue the point but I am here now and likey won't be 20 years from now when the dust settles and I generally get more than 20 years from my trucks, mowers and such. I have an Ford 8N tractor here in shop about 80 years old. Still doing the jobs it was built for. Course if the powers that be decide to make fuel unobtainable or more ridiculously priced then we are at now all bets are off .

MY 6421 is wearing a 28" bar and I've certainly had it buried and it works. I have no desire to trash the 6421 but upgrading to a 79 or 85 isn't as easy as it once was. I would prefer a dolmar 79cc kit but not for 350$!. Then the rest of the saw is unsupported. Parts, as I found with this thread, are becoming unfindable. I don't think it is wise to invest in a saw like this but just use it until it dies.

That is why a backup saw or my next saw using stihl parts is desirable. I'm not considering electric! ha! For under 350$ I can have a 660 clone with a 28" b&c delivered. It even has an adjustable carb. Stihl makes great stuff and makes a lot of parts for really old stuff too.

I have this thought about a larger rim sprocket to speed up the chain and really cut fast.
 
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there is no electric out in the boonies to recharge an electric , a genny solar wind, well i do not want to haul half of a garage out there, I do not see electric out preforming a 60+cc saw in my life time. Try hefting a 6hp electric motor ac or dc , then tell me again about electric replacing gas in a chainsaw. Just an old guy set in my ways. Course the powers that be will likely force the issue further by making fuel so expensive that there is no other choice, except for old school misery whips and double bit axes. Sad state of affairs.
 
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Comparing a 6hp industrial motor to one that is in a saw is like comparing a Briggs and Stratton to a saw engine.

The battery saws are not able to cover the > 45cc range yet. But electric motor and battery tech is improving fast. I'm already seeing professional line clearing crews using battery saws. One crew spent two days on the super steep powerline that goes up from near my place. They parked their trucks here and I could see from my home office when they left and returned and what gear they were carrying. They packed in for each day with extra batteries in their packs. They probably did not weigh much more than the usual gas can. I could hear them cutting and felling so I knew they wern't just going up there and goofing off.

The new CARB rules banning sale of new gas chainsaws with engines made after 2023 will spur development of larger battery saws. I think it's a dumb rule overall as clearing overgrown forests is more important, but CARB didn't listen to me. However it will create a market.