I am working on an old Homelite 150 Auto for a friend. I originally thought it just needed the carb rebuilt as it has spark. No luck getting it started. Thought it might be a reed or valve so...To make a long story short, I disassemble it totally to inspect everything. there are no reeds or valve. I de-carboned it while apart and inspected everything. Little to no carbon or wear everything looks great, so I reassembled it. Read that it could have a crankcase leak so I resealed all surfaces. Even replaced the oiler diaphram while it was apart. As I was setting the points I realized that the points closed 180 out.(piston down) Now I'm not a pro but I do know engines in general. How can this be as the points lobe is on the crank shaft?? Any help here would be appreciated.
Homelite 150 Auto
- Thread starter mferris72
- Start date
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sparks when points open
drops magnetic lines of force, induces high voltage in secondary windings and fires plug.
did you do lines and fuel filter?
drops magnetic lines of force, induces high voltage in secondary windings and fires plug.
did you do lines and fuel filter?
Did you try to prime it while it was together? Usually if you can squirt a little fuel mix into the carburetor and it hits or runs a bit all it needs is some fuel system maintenance.
Thanks Kevin, that's what I thought. Just wasn't sure. Yes I did fuel lines, filter and fresh fuel. Still nothing.
I tried priming it through the plug hole and carb w/fuel mix, starter fluid and WD40,Nothing.
do you have spark?
how about compression?
I have a really nice 150 auto that is currently going to a new home
kcj
how about compression?
I have a really nice 150 auto that is currently going to a new home
kcj
Yes good blue spark
Going to finish putting it together tomorrow and do a comp test
Points have to be set pretty close to specs or the timing will be off.
OnlyHomelites
ArboristSite Member
Check the spark plug wire around the boot...I just finished one for a customer that tested great spark with the plug out of the saw. Installed, it ran erratically if at all. The plug wires & boots on these saws sit awful close to the muffler and the insulation breaks down. My guess is your saw is doing the same thing and shorting to the case when the wire is installed on the plug.
Putting it back together and will gap points and coil. Plug wore look good and has the original installation sleeve on it. Going to look at it under a mag lite to make sure it's OK. Thanks for all the help guys. I'll let ya know how it goes.
Most handheld equipment has rather limited ignition capability, especially compared to automotive. Talking about max possible secondary voltage. Especially true of antiquated breaker-points magnetos. Bottom line: plug gap's gotta be kept tight, for spark to cross it, under compression. Best try for .022-.025" gap. Champion's gauge is best IMO- the one with the ramp around the outer circle. Way simpler than feelers too.
Voltage required for spark is much less in open air than @TDC of compression stroke, so that can fool you.
Gonna tell us what the compression-gauge said?
Voltage required for spark is much less in open air than @TDC of compression stroke, so that can fool you.
Gonna tell us what the compression-gauge said?
