Homelite Chainsaws

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Guy brought a 550 with no spark with coil and transformer removed and no plug.Searches I found plug# and test for spark with transformer wired separate.I did that and saw a spark and was not worried maybe just needed everything cleaned up.So did the usual carb kit,boot,fuel line,filter.Wants to start a pop now and then.Tried coil closer .007 and further .020 likes the original .012 the best but which part do I need now?Searches didn't help.Thanks,David
check out your coil HV wire (i.e.-spark plug wire). just recently went through that myself. maybe its the wire or maybe not. if you replace it you'll know that wire is definitely good. just sayin
 
Guy brought a 550 with no spark with coil and transformer removed and no plug.Searches I found plug# and test for spark with transformer wired separate.I did that and saw a spark and was not worried maybe just needed everything cleaned up.So did the usual carb kit,boot,fuel line,filter.Wants to start a pop now and then.Tried coil closer .007 and further .020 likes the original .012 the best but which part do I need now?Searches didn't help.Thanks,David
How strong of a spark is it? If it's obviously weak, that's one thing, if it's questionable, then I would eliminate the other usual variables such as compression, vac test, wiring, etc. Even though you've gone through the fuel system, I would still dribble a little mix in the cylinder, to eliminate the possibility of a fuel problem. Just my 1 cent.
 
Did check key for sheared and it's ok.Spark was weak and not steady when testing.Reason I wondered not coil it seemed like it reacted ok increasing gap (retard) and saw didn't kick back/when I lowered the coil (advance) got a few more kick backs.Compression is great.Saw still has writing on the bar and sprcket shows little use.Normal I'd get a coil but know nothing about this transformer.Thanks
 
There's a spring inside the transformer cup that contacts the tip of the spark plug. I've seen these springs be corroded or broken before. Also, there's contacts on the plastic transformer mounting piece. One of them (I think its the left side) needs to have a good contact with metal. I've seen cases where all that's needed to fix spark is just cleaning these contacts.

Dan
 
Gently pull on the wires coming out of the pickup coil and module assembly. See if the insulation stretches right where the wires enter the coil. This can cause a frustrating fire and no fire situation from the broken wire as it makes and breaks connection inside the insulation.

Sent from my SM-N910V
 
If you have a meter and want to check out the transformer, here's some pics from awhile back that gives an idea of readings.
DSCF1646.jpg


DSCF1647.jpg


DSCF1648.jpg


Dan
 
Thanks much guy's.I saw that post on the transformer but didn't know if my meter would do that.Since I saw it again and in a round about way have both parts coming asked electrians at work about the test(got to check my meter or get a different one).Anyway as soon as parts arrive I'll get back on it,for now got to finish an 075.Dave
 
Hey I just went out to the shop and took readings on a NOS ignition coil unit that I just got for the 350/360/450/550/650/750 series of homelite saws. This is the unit at the flywheel, not the trans former at the spark plug. Here's what she read....... .926 kilo ohms terminal to ground. 62.2 ohms lead to ground. .984 kilo ohms terminal to lead. I hope this helps someone to trouble shoot this ignition system.
 
Hey I just went out to the shop and took readings on a NOS ignition coil unit that I just got for the 350/360/450/550/650/750 series of homelite saws. This is the unit at the flywheel, not the trans former at the spark plug. Here's what she read....... .926 kilo ohms terminal to ground. 62.2 ohms lead to ground. .984 kilo ohms terminal to lead. I hope this helps someone to trouble shoot this ignition system.
Thanks,I'll have to get another meter.Sad part is I don't think owner will be able to start it.OK just a Free HF tester but transformer tested like post.Lack of sleep and no fire made I didn't remove and check coil .Think I'll wait and compare to new when it arrives.Thanks for now!!! Dave
 
Alright Dads, what does it mean when the Hi adjustment screw has absolutely no effect when you turn it? My Homie XL 901 (that will be the death of me) idles great and runs great at full throttle until you put it in wood. Then it acts like it starves for fuel and almost dies about 2 seconds into the cut. I figured it needed to run richer. I adjust the hi speed and no effect whatsoever. Has a new carb kit in it.

Will run all day until you put it in wood. Any help would make me sleep better. Thanks!
 
I was having a similar issue with another brand of saw which was running too lean no matter how much I opened the high needle. So I fattened up the low till it wouldn't run then increased the idle set screw till it would run, then was able to adjust the high until it 4 stroked at wot no load.
 
I had to play with the low jet screw and idle set screw a bit before the carb let me hit the sweet spot on the hi jet. This particular saw is known for having a temperamental carb after a good woods port, usually homie carbs are not so bitchy.
 
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