With the benefit of an hour or so spare this weekend, I stripped down the chainsaw to see if I could find out what was wrong. I removed the bar from the saw body and gave the area around the clutch and chain drive a good cleaning to get all the oiled up sawdust out of it. I then removed the exhaust from the cylinder head and removed the spark arrestor from the exhaust muffler and gave it a gentle clean with a wire brush although the mesh wasn't too caked in carbon to begin with. I then removed the carb from the cylinder head while leaving all the gas lines/primer bulb attached and gave it a good blow out with the compressed air line. I did destroy the gasket between the carb and the cylinder head and remade one from gasket card using an exacto knife. For good measure I threw in a new .325 chain from Home Depot (the original chain is still on the saw after 10+ years!) and put it all back together. Hey presto, it started second pull and runs and cuts like a dream again. Can't say I know for sure what fixed it, but my first recommendation would be to blow out the carb with compressed air.

Great forum here and a great education! I just picked up a Homelite 150 Automatic model UT 104324, serial number 380600059. It appears to have had little use, is completely old-school as far as safety brake and that sort of stuff, but I put a tank of 50:1 regular gas in it and it fired right up, idled just fine, and cut as well as its not-so-sharp chain could be expected to do. I have a couple of questions as I get to know and trust the saw, and any input is greatly appreciated. 1. Did I injure the engine with a short run of 50:1 fuel, and should the octane be higher than regular fuel? Should I definitely be using a 32:1 mix? 2. How do I know if the automatic oiler is oiling? The oil tank had oil in it, and I topped it off with bar and chain oil: how much oil residue should I see on the bar? 3. Does the safety tip wheel fit onto the roller tip bar on this saw, and can Bill Walcott send me one? 4. Is there a retro-fit toothy-poker plate available to mount on the engine face like more modern saws use? That seems like a good stabilizing/safety device. 5. Is the Oregon 72 the proper chain? The bar protrudes 16 inches past the engine face. Thank you all so much for what you have created here: this has been a great tool! Glen Moore, Seattle WA

Rock: While your at it get the diaphram kit , it is not much of a $$ adder. A weak diaphram can cause poor performance also . Older saws with a little dirt or varnish along with a weak diaophram will cause a lot of headaches. Ensure to check all your fuel lines for tightness a small air leak can cause serious damage long term. Also as previously suggested , ensure your fuel filter has no restriction you should be able to blow through it . If all is good then just a jet orifice cleaning with a concentrated fuel cleaner should get you going :)

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