Old Homelite chainsaw question

[kerrygeek]

Apparently for a few years before my father died, instead of fixing his chain saws he just bought new ones. I have 4 old saws I'm trying to resurrect so I can have a backup to my main saw. I started working on an old (probably 20 years or so) Homelite 18" saw but I can't get a spark no matter what I do. I've tried a new plug and even a new coil. I set the distance from the coil to flywheel with a business card like I've always done before, made sure I got good connections but even with a new coil I still don't get a spark. I've checked/cleaned the coil mounts and ground screws and tried unplugging the ground wire that goes over to the kill switch. The ignition on these things only has a couple of parts so there can't be too much wrong - or that's what I'm telling myself. The magnet in the flywheel is fine and the saw really doesn't look like it has much use on it. I've got continuity on the plug wire to the coil. Do you guys have any ideas of what else I can check?

Thanks,
Kerry in NE TX.

 

[Phill Tibbetts]

Try something thinner than a credit card like .010 feeler gauge.

 

[kerrygeek]

Try something thinner than a credit card like .010 feeler gauge.

I'll get out there tomorrow and try it, thanks. The card measures .012 with my 50 year old micrometer...

Kerry

 

[Phill Tibbetts]

Did you clean off any rust or dirt from the rotor and stator?

 

[rustred]

Apparently for a few years before my father died, instead of fixing his chain saws he just bought new ones. I have 4 old saws I'm trying to resurrect so I can have a backup to my main saw. I started working on an old (probably 20 years or so) Homelite 18" saw but I can't get a spark no matter what I do. I've tried a new plug and even a new coil. I set the distance from the coil to flywheel with a business card like I've always done before, made sure I got good connections but even with a new coil I still don't get a spark. I've checked/cleaned the coil mounts and ground screws and tried unplugging the ground wire that goes over to the kill switch. The ignition on these things only has a couple of parts so there can't be too much wrong - or that's what I'm telling myself. The magnet in the flywheel is fine and the saw really doesn't look like it has much use on it. I've got continuity on the plug wire to the coil. Do you guys have any ideas of what else I can check?

Thanks,
Kerry in NE TX.

what is the models of these saws. i have a big collection of homelite's. the old ones have points and the newer ones are electronic. like to know what these are.

 

[kerrygeek]

Did you clean off any rust or dirt from the rotor and stator?

I haven't even pulled the flywheel yet, that's probably the next thing I should try, thanks!

 

[kerrygeek]

what is the models of these saws. i have a big collection of homelite's. the old ones have points and the newer ones are electronic. like to know what these are.

The manual says UT10518, on the side of the saw it says 4618C. I also have a smaller one that says 3514C that I haven't started on yet. I'm trying to figure out about how old they are, I doubt they are electronic. My father died in 2015 and the last saw he had was the Husqvarna I'm using these days, he probably didn't use any saw his last 4 years. I'm thinking these are from around 2004 or so, I think that's when he got the Husky but I'm not sure. They've lived in the shop over at the farm for decades, now that I'm retired and only 5 mins from the farm (instead of 7 hrs) I decided to see if I can either get them going or give them to somebody who needs a saw and can get them running. I really don't need 4 backup saws! I've got the 2 Homelites I mentioned, an old Poulan and I think one other. I'm not trying to collect saws but one of the smaller ones might be handy to keep around.

Kerry

 

[john in la]

According to google UT10518 is a 46cc 18 inch saw built in the early 2000’s. It has a Solid-state electronic ignition (magneto) set at .010 to.012. It uses a Champion RCJ6Y plug set at .025.
If the magnet is good and the magneto gap is right your mag is most likely bad. About $17 on amazon. HM 300953003.

https://www.partswarehouse.com/Homelite-UT10518-42cc-46cc-Chain-Saw-s/345075.htm

 

[rustred]

The manual says UT10518, on the side of the saw it says 4618C. I also have a smaller one that says 3514C that I haven't started on yet. I'm trying to figure out about how old they are, I doubt they are electronic. My father died in 2015 and the last saw he had was the Husqvarna I'm using these days, he probably didn't use any saw his last 4 years. I'm thinking these are from around 2004 or so, I think that's when he got the Husky but I'm not sure. They've lived in the shop over at the farm for decades, now that I'm retired and only 5 mins from the farm (instead of 7 hrs) I decided to see if I can either get them going or give them to somebody who needs a saw and can get them running. I really don't need 4 backup saws! I've got the 2 Homelites I mentioned, an old Poulan and I think one other. I'm not trying to collect saws but one of the smaller ones might be handy to keep around.

Kerry

Well I call them the new saws. The ones I’m talking about are from the 60’s and 70’s. Yes they are electronic.

 

[kerrygeek]

According to google UT10518 is a 46cc 18 inch saw built in the early 2000’s. It has a Solid-state electronic ignition (magneto) set at .010 to.012. It uses a Champion RCJ6Y plug set at .025.
If the magnet is good and the magneto gap is right your mag is most likely bad. About $17 on amazon. HM 300953003.

https://www.partswarehouse.com/Homelite-UT10518-42cc-46cc-Chain-Saw-s/345075.htm

If what you're calling the magneto is the coil with the plug wire attached, I just got a new one on Amazon. So if it has electronic ignition does it not have points and a plunger under the flywheel like the old Briggs motors had? I haven't dug under the flywheel on a 2 stroke in a long time. I don't know for sure that the old coil was bad but I put the new one from Amazon on today and it didn't fix the problem.

Thanks,
Kerry

 

[kerrygeek]

Well I call them the new saws. The ones I’m talking about are from the 60’s and 70’s. Yes they are electronic.

I guess they aren't all THAT old. I rebuilt one for my grandfather when I was in HS back in the 70s, it was an old Craftsman and had a big gear drive on the side, I think I remember the gear was made of phenolic or something like that. I got it running great but it was a heavy sucker.

 

[Bob Bancroft]

I guess they aren't all THAT old. I rebuilt one for my grandfather when I was in HS back in the 70s, it was an old Craftsman and had a big gear drive on the side, I think I remember the gear was made of phenolic or something like that. I got it running great but it was a heavy sucker.

In the mid 70's I was working at a farm equipment dealership. I was switched over to chainsaws as the boss, who had previously taken care of them, needed to give his time to other issues. The Arab oil embargo had occurred and everyone who shouldn't be near a small engine was buying a chainsaw. I ended up full time in that corner for the next several years. Somewhere in that time period they were already going to electronic ignitions. They became stupid simple as the part which had previously been the coil was now everything. The electronics which replaced the points and condenser were molded into the coil. I don't recall that you could tell the difference by looking at them. Your air gap is fine, it isn't that critical. So you do have a dilemma. As this is the age of junk parts, is that what you're getting? Is someone producing a coil for the old point and condenser system? I can't imagine that. As Homelite has been dead and gone for years, I assume getting proper parts, or any parts, is a real adventure.

 

[john in la]

If what you're calling the magneto is the coil with the plug wire attached, I just got a new one on Amazon. So if it has electronic ignition does it not have points and a plunger under the flywheel like the old Briggs motors had? I haven't dug under the flywheel on a 2 stroke in a long time. I don't know for sure that the old coil was bad but I put the new one from Amazon on today and it didn't fix the problem.

Thanks,
Kerry

I have no personal experience with that model so I can’t speak intelligently from personal experience. But if you look at the parts breakdown I linked to you can see it doesn’t have points under the flywheel. That is why I gave you the link so you could verify it for yourself.

Did the part you got already match the part number I gave you that I got from the link I posted.

These things are super simple. If the magnet is clean of rust the coil (as you call it) is a drop in one and done repair. Everything is contained in that one unit to make it fire every time the magnet goes past. Yes the spark plug could be bad but that wouldn’t stop the coil from firing at the end of the wire.

If it were me based on what you have said I would send the coil back to amazon as defective and look and see if you can find a different brand and try that. The original OEM part is NLA.

 

[Mike(NEOhio)]

Leon Crouch has a lot of old Homelite parts and good advice. I got parts from him a couple of times. He has a website.

 

[DaveBN]

Like John in the post above, I suspect that replacement coil is bad or incompatible. That is wrong part and wrong part number. Did you order the coil by part number or just order the same one that was on there when you opened it up? Maybe the one that was on there was wrong.
I would check compression on all those old saws before I wasted any time or money on them.
Dave

 

[kerrygeek]

Like John in the post above, I suspect that replacement coil is bad or incompatible. That is wrong part and wrong part number. Did you order the coil by part number or just order the same one that was on there when you opened it up? Maybe the one that was on there was wrong.
I would check compression on all those old saws before I wasted any time or money on them.
Dave

I have a compression tester I used on my old 8n a while back but it feels like the compression on the saw is very good when I pull it through. The part number is on the front of the coil and it matches the number on the original and also the part number I found online so I think it's the right one. It's possible that the coil I got is bad, I assume they are all from China these days so the right part number might not mean much or it might not even be good. I checked it with a meter and the resistance readings are about what I'd expect but I've decided I might not know what to expect!

Tnx,
Kerry

 

[CraigWis]

Something to check is the wire from the Kill switch. Is it grounding the coil out
the other thing is the coil is it a Cheap one or one from a Good company. I have had a lot of Bad coils off the shelf that wound not spark or lost spark at High RPM's

 

[kerrygeek]

In the mid 70's I was working at a farm equipment dealership. I was switched over to chainsaws as the boss, who had previously taken care of them, needed to give his time to other issues. The Arab oil embargo had occurred and everyone who shouldn't be near a small engine was buying a chainsaw. I ended up full time in that corner for the next several years. Somewhere in that time period they were already going to electronic ignitions. They became stupid simple as the part which had previously been the coil was now everything. The electronics which replaced the points and condenser were molded into the coil. I don't recall that you could tell the difference by looking at them. Your air gap is fine, it isn't that critical. So you do have a dilemma. As this is the age of junk parts, is that what you're getting? Is someone producing a coil for the old point and condenser system? I can't imagine that. As Homelite has been dead and gone for years, I assume getting proper parts, or any parts, is a real adventure.

That's what was bugging me, there's really nothing else to go wrong with these things, there's nothing to them. I've never been able to not fix one before but they are usually carb problems. ;-) I'll probably pull out the new coil and send it back then find a different one and try again.

Thanks,
Kerry

 

[kerrygeek]

Something to check is the wire from the Kill switch. Is it grounding the coil out
the other thing is the coil is it a Cheap one or one from a Good company. I have had a lot of Bad coils off the shelf that wound not spark or lost spark at High RPM's

Yes, I checked it with a meter and can see it turning on and off but I tried it with the kill switch wire completely unplugged. Yep, it's a cheapo Amazon coil. I think I'll try it again and order another one from a different vendor.

Kerry

 

[TomA in CA]

I am having trouble with a predator 6.5 212cc. It ran beautifully for many years.
Always started on 1-2 pulls. Makes me wonder if these imported engines have hotter spark than the old domestic engines.

My current problem started when the ground wire to the coil broke and shorted out. I replaced it with a new Amazon coil. I left the ground wire unhooked to eliminate problems with the switch.

It would not start at all. I figured the new coil was no good. Amazon has a deal where you can order 3 coils cheap I guess people are having trouble with bad coils.

I finally realized there is a little box over by the switch that I believe is the capacitor. I hooked up the ground . Now it runs sort of. Hard to start and runs like crap. I am thinking of splicing the wire on the original coil and trying that.

I had thought of just buying a new predator. They are not $100 any more they are $150 with the tariffs. You have the choice of EPA or Carb so I am guessing they are different. Possibly another case of new stuff being crap.

I just want my old predator on my old Troybilt tiller running good.