Do any of you folks fix small, two cycle engines too? Like for string trimmers? I have an old Homelite ST-80 string trimmer, 27 cc engine or something like that, the engine is made my Kawasaki I think. It won’t start unless I take the air cleaner off. When I took I apart, it’s pretty clear it needs a carb rebuild with all new gaskets. Any ideas for a good vendor?
A small engine repair shop might be able to give you a lead.
I’ve bought from these guys (don’t see your model, though):
@GeorgeSanJose if taking the air cleaner off makes it run, my first suspicion would be the the foam needs to be cleaned. Soap and water works well. I have the same antique trimmer, and all I’ve ever replaced were the spark plug, primer bulb, and the fuel lines.
If old fuel was allowed to evaporate and gum up the carburetor, try spraying some carb cleaner (AKA lacquer thinner) thru the various ports and holes. Total disassembly should not be necessary unless your diaphragm is brittle.
Beware of “blind holes” if you use the straw that comes on the can. Those holes, with no other means of escape, will blow the cleaner right back in your face. Ask me how I figured that out.
I use Jack’s small engines for mail order part. Have about everything. Just google.
Remove the obstruction in in the exhaust,maybe carbon or a mud daubers nest in there,some gaskets you can make yourself out of RTV or paper or gasket material(I got away from string trimmers years ago)
Thanks for the good info to all.
Yeah @“MG McAnick” I learned that about problem the hard way too! Fortunately I learned it on a prior carb cleaning incident, so I always wear eye goggles now when doing the “spray-clean the carb” job.
I’ve cleaned the foam air cleaner inner soap and water, seems to be pretty clear, easy to blow through now. It helped, but didn’t entirely solve the problem. The fuel line and spark plug check out ok. I’m unaware of a primer bulb, don’t think mine has that feature. When I removed the carb for a spray cleaning though, I noticed the gasket between the carb and the engine is totally shot. I think this is the problem, as the fuel is routed (in a very strange way) along that path from the fuel inlet to the carb intake hole. That gasket forms the top of the path. The diaphragm you mention isn’t in that good of shape either, but it appears to be intact still. If I can find a gasket set, the diaphragm will probably be in it too.
The other problem I have with this rebuild is locating a new fuel filter element. It’s a ceramic cylinder, the current one dissolved into dust in front of my eyes when I removed it. I think these elements are probably still available in one form or another, so I should be able to get past that hurdle. The gaskets are the bigger problem. I might try using an old bicycle inner tube to make my own gasket if I can’t find a kit.
I don’t think an inner tube will make a good gasket as the rubber is not impervious to gasoline, especially this “modern” crap with ethanol.
I just went out in my garage to look at my trimmer. I don’t see a model number on it, but it may have been on the missing air cleaner cover. All I have left is the sponge. I’d have sworn it was an ST-80, but it may be a different year if yours has no primer bulb.
"I don’t think an inner tube will make a good gasket as the rubber is not impervious to gasoline, especially this “modern” crap with ethanol. "
I’ve got a station near me that sells Rec90 gasoline that has no alcohol, just straight gas! They sell lots of it for boats, snowmobiles, lawn equipment…
I love the stuff.
I think I’ve found a source for the parts I need. Thanks to everyone for their assistance.
Good luck with that carburetor @George. The pulsing valve was a real pain on my chain saw and leaf blower. It was a job more suited to a watch maker.