So bought a chinese saw (holz g070)

[J D]

The condenser doesn’t work the way you're thinking it does. It's job is to absorb excess energy that would otherwise burn up the points. Remove the condenser & try it, if it runs the condenser is breaking down at operating voltage.
I'd be guessing a wire is damaged or a connection point somewhere on the points assembly is intermittent. If the plug lead is removable I would separate it & check the resistance of the HT lead & whether it fluctuates if you move the lead around.
As mentioned earlier, you should be able to get the coil to spark by momentarily connecting ~5V across the primary.
@heimannm probably deals with this sort of thing a bit & may have some valuable insight

 

[heimannm]

The condenser does "absorb" the high voltage when the points open, but it also discharges back through the coil speeding the collapse of the magnetic field and that is essential to achieving a good spark on a magneto type ignition. Most condensers will be 0.2 µf or so. You can generally check a condenser with a multimeter set to the highest ohms scale and alternately switch the meter leads to the wire and the body of the condenser. What you are doing is using the internal battery of the meter to slightly charge the condenser, it will read as an open circuit, but when you switch the leads there will be a slight "blip" on the meter as the condenser discharges through the meter.

The secondary windings (spark plug lead) will generally be between 5,000 and 10,000 ohms (5k to 10k Ω) and the primary windings (points lead to ground) around 1Ω.

Clean your points again using very fine emery paper (200/400/600 grit) until they shine like a mirror then clean them with a good solvent (carburetor cleaner) then finally drag a clean piece of paper through them 8-10 times and I suspect you will have a reliable spark once again.

Mark

 

[sliceoflife]

When you say across the primary coil; where should I apply the voltage? From the coil unit's ground contact to the coil unit's main contact (that goes to the points/condenser)?

 

[J D]

When you say across the primary coil; where should I apply the voltage? From the coil unit's ground contact to the coil unit's main contact (that goes to the points/condenser)?

Yes.
I'd follow Marks advice first though. If the points aren’t well smoothed & free of any dust etc, you won't get many sparks out of em

 

[farmhard]

Holz may have asked you if the part is available locally, however their tactics seem to be delay with endless stupid emails and forget the topic. You will be dealing with several people who don't read or understand and infuriate you further.
There was a batch of bad pistons that would not fit over the rod. I sent pictures of verniers and measurements and we went in circles for months. There was also a batch of cylinder heads that werent' bored properly and cross hatch was uneven. Same thing. All the Homelite carbs I had in stock had internal damage where they would somewhat operate with both jets closed all the way.
There was a problem with the design of their decomp valves and I would swap to an OEM which I think is $8-10, the aftermarkets are known to come apart.
With shipping and brokerage I can usually buy OEM stuff at or near the same price with the exception of jugs.
Now if you made it this far, I have had starter ropes pull off the first time I use them, pawls jam, bearings that were worse that the used ones and seals that bend bc they are too thin. My question is why not repair an original Stihl and know it will last forever rather than spend your day trying to figure out how to make junk not junk anymore?
The last used Contra I bought was a carb clean and it is running and I spent FAR LESS than you will.

 

[sliceoflife]

So all the parts have arrived. The points I bought for the skill 1661 don't quite fit every other part of them is identical but the little metal band/spring doesn't fit... too long and screwhole too far from mount. thought I got lucky and found a match, but nope. So I pulled the existing points and polished them to one micron and cleaned them with carb cleaner like suggested. I also replaced the coil and the condenser. May never know which part was bad if it starts working now but I'd rather not have to take the flywheel off again if I can avoid it. Put it back together and checked for spark. definitely significantly stronger than it was... shocked myself through my gloves with a quarter pull.

Not going to try to get it running in the middle of the night but hopefully tomorrow on my lunch I can see if it'll actually run now.

The Homelite 775d that slipped every third or fourth pull started slipping 100% of the time so I took the starter apart put it back together with one less shim in there and it seems to grab now.

Carb kit for the 1130 G is here but I might hold off on that till the weekend as I don't want to rebuild it and find out there's something else wrong and then have to stop working on it... itd bother me.

 

[sliceoflife]

New rule... I dont care how stupid it seems to you.... no suggestion of something to check is off the table or insulting to me... I want that as my signature.


So at lunch today the saw was back to what it was all along... went from good spark to no spark real fast and no amount of tinkering fixed it.... figured the spark plug wire must have an internal break, so went out after work and bought a new wire. No better. Decide to swap the condenser back. No better. Decide to pull and polish points again, at least see if they are burnt up already.


And after knocking off the flywheel, for AT LEAST the 20th, and honestly, probably the 30th time... I notice.... hmm... looks like theres a notch for a key in this.... then I think of the points setup... and OF COURSE the flywheel is keyed. Honestly that may be the only thing that was ever wrong is the key was missing and the magnets weren't oriented right... ie the timing (fixed on this saw) wouldn't be correct.

Stuff a bit of wire in there as a makeshift key and it starts first pull and roars like a bat out of hell... no clue how much I have the idle throttle screw in, but a lot... so I kill it, and come up here to talk about how ignorant I am.

Shame I wasted all that money and time and destroyed the spark plug wire trying to fix it.

 

[farmhard]

New rule... I dont care how stupid it seems to you.... no suggestion of something to check is off the table or insulting to me... I want that as my signature.


So at lunch today the saw was back to what it was all along... went from good spark to no spark real fast and no amount of tinkering fixed it.... figured the spark plug wire must have an internal break, so went out after work and bought a new wire. No better. Decide to swap the condenser back. No better. Decide to pull and polish points again, at least see if they are burnt up already.


And after knocking off the flywheel, for AT LEAST the 20th, and honestly, probably the 30th time... I notice.... hmm... looks like theres a notch for a key in this.... then I think of the points setup... and OF COURSE the flywheel is keyed. Honestly that may be the only thing that was ever wrong is the key was missing and the magnets weren't oriented right... ie the timing (fixed on this saw) wouldn't be correct.

Stuff a bit of wire in there as a makeshift key and it starts first pull and roars like a bat out of hell... no clue how much I have the idle throttle screw in, but a lot... so I kill it, and come up here to talk about how ignorant I am.

Shame I wasted all that money and time and destroyed the spark plug wire trying to fix it.

I loosened the flywheel on an 036 and then took the clutch off and sheared my key or something somehow while rebuilding it. Don't feel bad. You should not have had to fix this.....YET.

 

[sliceoflife]

Thanks. To clarify though. this is a used skil 1661 I bought as "put away running" for a project saw that had no spark when I got it home... not the holz g070 that started the thread. Thankfully the holz didn't have starter issues. This thread has become kind of my SAD blog.

Holz issues were limited to overly weak clutch springs (chain spun at idle) and a bent arm for the decomp (decomp didn't work) ... plus general weakpoint in the cast parts (flywheel guard ribs breaking easy). Its actually become the saw I grab when my super xl vapor locks, the pullcord snaps on my cs900evl, and everything else is disassembled for carb rebuilds and I need something that I know will run... downside is I wind up bucking a half cords worth with a 40lb saw and feel like I ran a marathon.

 

[farmhard]

You need to get a yellow saw. Maybe a 570 or 700.

 

[sliceoflife]

My very first chainsaw was a 250. It was the first carb rebuild I did, once I rebuilt the carb I cut up some bird cherry with it and after a handful of cuts the clutch started slipping. I had bought it to Mill with a 36-in bar and everyone was telling me it wasn't enough saw for that anyway so I sold it at a big loss to someone who knew what they were doing and bought the g070.

Looking back the chain was probably just dull and I was leaning into it too much, wish I still had it but that ship sailed. If I buy a yellow saw at this point I'll probably be keep my eyes open for one of the rare big ones like a 125.

 

[farmhard]

I picked up a Contra for $100 with a bad starter clutch, missed out on a gear drive and then bought the 2nd Contra for $300 US with good compression and rebuilt the carb. Both are very dependable saws. My local Stihl dealer will not sell parts nor work on them so I now carry more used Stihl equipment than they have new -and the parts to fix them.

 

[sliceoflife]

I like my clone despite the issues... honestly if timing had worked out and that member in Europe (David) who lists the contras (and other saws)in the for sale forum in the 500ish$ range on occasion had put one up before I bought the clone maybe I'd only own two saws, a contra and a bucking saw. As it is I hope the super xl and the 1130g become my "bucking " and "milling " saws and the rest are just fun saws, once I get the 1130g up and running.

 

[sean donato]

You really just need to get something a little more mainstream. Have a lot less issues.

 

[sliceoflife]

Yeah I know. My buddy was telling me the same thing. Got 8 saws in parts in my basement; he's like "You could have bought a 3120 for what you spent on these". I did the math and was like... yeah about; but this was more fun.

Plus I mean I don't need both the 1661 and the 900, so I'll probably sell one once they're both running; and I might recover some funds from the two 775's when I sell them. And knowing I put in the work to get the saws I wind up with running well; I'll appreciate them more. And I guess I've got some spare parts for the 1661, and some random homelite (the saw the replacement points were designed for)... It'll go good with the 394xp Clutch cover I bought for the 394 the seller never shipped.

 

[sean donato]

Hehe I pretty much was thinking the same thing as your buddy. That and I know parts arnt the easiest to come by for half those saws. Hopefully you can get one or two to work, so you can get some work done.

 

[sliceoflife]

900 and g070 both running. I think both 775s and the super xl are running now but I haven't given them enough real work to know.

Finishing up getting the 1661 and the 1130g running, then I will get back to milling. I'll buck some with the 775s and super xl to confirm they're running and decide what I'm doing with them, then gotta figure which of the 1661 and 900 I want to keep if not both.


Then I'll probably let the g070 and/or the 1130 live in my mill.

 

[sliceoflife]

Cut a few slabs on my lunch with the 775's.

So the 775G started up and ran perfect as far as I could tell. About as good as I could ever imagine a saw that old that was anything other than new old stock running. No issues... except the chain is dull as dirt (duller than the 900's chain was when I got it)... so It couldn't really cut much; not for lack of the saw trying though. Put some work with a file but it still wasn't nearly enough... Need to stick that chain in the cheapo power grinder I've got and get those teeth sharp so I can really see what it can do. If I keep it I will at some point buy a .404 or rim drive for it... Stole the one I HAD bought for it to put on my 1130g... so it's got the old 1/2" back on it... and that sprocket is almost Dead as is (spurs damn near worn through)... and no reason to buy another 1/2". Figure I'll see how much life the current chain has left once I get it sharp and when the chain goes; so will the sprocket.


The 775D does show its flaws when I ran it side by side with the 775g, but on the other hand it has a new chain on it; so it cuts like crazy... After sitting the past couple months, now the clutch hesitates to grab; but once it does it runs fine... suspect it's just gunked up inside the clutch. Basically have to Run the saw WOT for a second or two before it shakes loose and chain grabs; then it cuts just fine. And of course; compression much lower than the 775G (I assume the piston damage/scars explain this)... but still runs strong and cuts through maple like butter (again with the new chain). Might wind up using this saw to finish bucking the small logs I need to (maybe 30-40 12" diameter cuts or so); just for kicks; put that chain to use before I get rid of the saw. Doubt I'm going to keep it... fun little saw; but deserves to be a project saw for someone who wants to clean up the piston/etc and make it actually the kind of "ready to use" saw it was sold to me as. I'd probably keep it if I hadn't lucked into such a nice 775g trying to buy parts to fix it up... but such is fate.

Spark plug for the Homie Super XL is here, but I didn't take it out today. Wanted to tune/test the 775s.

Still hesitating to rebuild the 1130g; didn't have time this weekend; so looking like next weekend.

Might get time to put the B&C back on the 1661 and tune it and see if it's a runner now on my lunch this week; but Im pretty busy so again probably waiting on the weekend.

 

[sliceoflife]

Hit the 775G with the file again. Still not as sharp as I want, but maybe as sharp as I can easily get it; given the condition/wear on the chain on arrival.

Bucked down a log and a half. Saw fires on second pull with choke and starts on first pull off choke. Purrs like a (large) kitten on idle and runs like a brand new saw. Best $120 I've spent on saws yet.

New plug in the Super XL and it started up and idled like it was going to run perfect... BIG difference between the old plug and this one. But in the cut it started having issues again. Took the carb out and the metering lever arm was once again too high. Fixed that and tried again... Found it was very tricky getting the H needle tuned in where it would not cut out (governor?... does this saw even have one?) when revved before even sticking it into the cut. Once I got it set right; it ran like a champ... but there is a hair's width of leeway on that H needle between virtually instantly flooding or dying when revved. May have to stick some teflon tape or threadlock or something in there to make sure the vibration doesn't shake it out of place while I'm using it.


Wouldn't surprise me to find there's an air leak or something.... just in general the saw feels Rock solid right after starting it cold; but in use and once it's hot; feels a lot more sensitive... Jostle it too much when idling to let it cool down and it may stall out... whereas right after startup (cold); I could throw it at a wall and it'd probably keep idling without a complaint. Hoping it's just the carb needles losing position; but worried it's air leak or something (not sure what all could explain that behavior).


To explain the running/tuning behavior better... Low setting really likes about 7/8 turn to 1 3/8 turns out of seated... outside of that it wont run for more than a second or so. Sweet spot feels right around 1 turn out.

High setting; if I sit there with the saw warmed up, and open up the throttle more than the tiniest bit (maybe anything more than 10% throttle, all the way to WOT) It will almost instantly die. This happens if the H is too far OUT or too far IN... can't tell any difference in behavior. It doesn't overrev and die or anything... doesn't have time to... it's as fast as if I hit the kill switch. If I IMMEDIATELY let off; it'll recover sometimes; but more than half the time; I can't get of the throttle fast enough and it just stops dead. And I mean it dies INSTANTLY... if the H tune is way off; saw barely/doesn't even start to rev up... it really acts like I hit a kill switch. Idling fine... give the throttle a tiny squeeze and saw dies. If I were just listening to the audio; might not even know the saw was given any throttle... would sound like it was just idling and spontaneously died. As I get closer to where the H adjust needs to be; it'll rev up more and more when I squeeze the throttle (the closer I get to the correct setting) before it instantly dies, but never hitting full revs... we're talking fractions of a second here. Again this happens coming at it from BOTH sides of the adjustment; too rich AND too lean.

Takes a good few minutes of inching the H tuning in and out a degree at a time to find the spot where it will run with the throttle open... Honestly couldn't say offhand where exactly it is; but I'd GUESS it's in the 3/4-7/8 turns out from seated range. Again this behavior seems to only be a problem after the saw has ran for a minute or two at least... so maybe not hot... but with the saw stone cold; right after the first startup it doesn't happen. I can start the saw; let it idle for a minute and get through a cut or two and then it starts happening.

When it's dying when revved and I'm trying to tune... Saw usually starts right back up on the first pull... so doesn't feel like flooding.


I Did not change the gas line or filter. Gas line feels nice and pliable and filter looked fine to me... possibly fuel filter clogged up? If not; any other ideas? Just a really sensitive carb for the tune and needles shaking out of the correct settings in use? Am I that lucky?

 

[farmhard]

Hit the 775G with the file again. Still not as sharp as I want, but maybe as sharp as I can easily get it; given the condition/wear on the chain on arrival.

Bucked down a log and a half. Saw fires on second pull with choke and starts on first pull off choke. Purrs like a (large) kitten on idle and runs like a brand new saw. Best $120 I've spent on saws yet.

New plug in the Super XL and it started up and idled like it was going to run perfect... BIG difference between the old plug and this one. But in the cut it started having issues again. Took the carb out and the metering lever arm was once again too high. Fixed that and tried again... Found it was very tricky getting the H needle tuned in where it would not cut out (governor?... does this saw even have one?) when revved before even sticking it into the cut. Once I got it set right; it ran like a champ... but there is a hair's width of leeway on that H needle between virtually instantly flooding or dying when revved. May have to stick some teflon tape or threadlock or something in there to make sure the vibration doesn't shake it out of place while I'm using it.


Wouldn't surprise me to find there's an air leak or something.... just in general the saw feels Rock solid right after starting it cold; but in use and once it's hot; feels a lot more sensitive... Jostle it too much when idling to let it cool down and it may stall out... whereas right after startup (cold); I could throw it at a wall and it'd probably keep idling without a complaint. Hoping it's just the carb needles losing position; but worried it's air leak or something (not sure what all could explain that behavior).


To explain the running/tuning behavior better... Low setting really likes about 7/8 turn to 1 3/8 turns out of seated... outside of that it wont run for more than a second or so. Sweet spot feels right around 1 turn out.

High setting; if I sit there with the saw warmed up, and open up the throttle more than the tiniest bit (maybe anything more than 10% throttle, all the way to WOT) It will almost instantly die. This happens if the H is too far OUT or too far IN... can't tell any difference in behavior. It doesn't overrev and die or anything... doesn't have time to... it's as fast as if I hit the kill switch. If I IMMEDIATELY let off; it'll recover sometimes; but more than half the time; I can't get of the throttle fast enough and it just stops dead. And I mean it dies INSTANTLY... if the H tune is way off; saw barely/doesn't even start to rev up... it really acts like I hit a kill switch. Idling fine... give the throttle a tiny squeeze and saw dies. If I were just listening to the audio; might not even know the saw was given any throttle... would sound like it was just idling and spontaneously died. As I get closer to where the H adjust needs to be; it'll rev up more and more when I squeeze the throttle (the closer I get to the correct setting) before it instantly dies, but never hitting full revs... we're talking fractions of a second here. Again this happens coming at it from BOTH sides of the adjustment; too rich AND too lean.

Takes a good few minutes of inching the H tuning in and out a degree at a time to find the spot where it will run with the throttle open... Honestly couldn't say offhand where exactly it is; but I'd GUESS it's in the 3/4-7/8 turns out from seated range. Again this behavior seems to only be a problem after the saw has ran for a minute or two at least... so maybe not hot... but with the saw stone cold; right after the first startup it doesn't happen. I can start the saw; let it idle for a minute and get through a cut or two and then it starts happening.

When it's dying when revved and I'm trying to tune... Saw usually starts right back up on the first pull... so doesn't feel like flooding.


I Did not change the gas line or filter. Gas line feels nice and pliable and filter looked fine to me... possibly fuel filter clogged up? If not; any other ideas? Just a really sensitive carb for the tune and needles shaking out of the correct settings in use? Am I that lucky?

If you are going to use the saw I'd change the filter and hose to make it reliable. I'd also do the crank seals before it implodes rather than after. If you are chasing a problem start with the cheap easy fixes and rule them out. Try wiggling the clutch and flywheel and see if there is play in the bearings.