Obviously, a worn t shaft/ carb boss will have an affect on runability. (The shaft is serviceable BTW. It is all subjective to how much wear. Many of these still fail the "Gumout Test" at the throttle shaft and still run good enough. What may be helpful, is to remove the idle screw/ jet from the side of the carb and spray your jet spray in the passage as the engine is running, reinstall the jet and see if it smoothes out. Go ahead and spray down the carb throat too to help releave the valves of any deposits from old fuel etc. I've found this helpful many times. There are also one or two "o" rings around the main nozzle up in the stem of the carb to replace. My own take on carb cleaners such as Gumout or Seafoam (preferred) is to use it for a mowing, maybe let it sit overnight and re run the engine with tank topped off with fuel to keep it from laying in the carb and affecting seals in the carb. Used as directed the stuff is fine, but sometimes folks get over zealous with the stuff.

UCL is highly recommended for ALL classic cars especially when they are not often driven. 1- 5 tankfills a year means that petrol (USAterm = gasoline, gas) is in fact always old, somewhat deteriorating and collecting condensed water. Nowadays one should absolutely avoid bio-ethanolized petrol because some materials (metalparts, seals, rubbers; from petrolfill-entrance to and including exhaustpipes) oxidate and or desintegrate because of the ethanol and waterattraction. In Dieselengines UCL lubes the Dieselpump which nowadays is not lubed by the Dieselfuel anymore because Sulphur had to be eliminated from this fuel The Sulphur in the olddays Dieselfuel, lubricated the Dieselcompressionpump better than the modern Dieselfuel does. UCL protects/has benificial effects, also when fuel is not streaming or dried up (a thin protective oily layer of UCLoil stays on all surfaces before the burningstage, when the gasoline has evaporated after some days of stand-still) : Less rust in fuel tank Rubber gaslines don't dry out Petrol- and Dieselpumpparts (electric AND mechanical pumps benefit); membranes are lubed Carburettor is lubed (critical for copper and other non-ferroparts) Inletvalves benefit Cylindersurfaces are lightly lubed during firing and also already during the coldstart. UCL implies that only oil that combusts properly and burns fully, should be used. ONLY, ONLY AND ONLY 2-Stroke Oil does that. It will not carbodeposit on internal engineparts. Some people use engineoil, ATF or whatever. DON'T DO THAT, EVER. ONLY 2-Stroke oil is specially designed for nicely burning with gasoline and Diesel! Use cheap, the simplest undoped 2-Stroke oil, it may be not, half or fully sythesized. Use NOT the stuff disigned for modern 2-Stroke engines, as it possibly contains agressive dopes (Bad for aforementioned materials) . For years now, I use 1 part 2-stroke oil on 200 parts gasoline (ratio 1:200) . DIESELENGINES: 1 L for every 60 L of Diesel (ratio 1:60). Try to ride your fuel tank as empty as you dare before adding fuel, FIRST add the 2-Stroke oil so it mixes by and with the flow of fuel pumped Expect to use 50 liters of petrol? First add 250 ml (1/4th liter) 2-Stroke oil (= 2-T). This is a small beerglass on an average fill. Better use a dispenser with marks, though.... 40? 200 ml 30? 150 ml 60? 300 ml So every 1 L of gas, first add 5 milliliter of 2-T. Ratio is then 1:200. Sometimes I underestimate the needed gasoline to fill-up and allready added the 2-T. No problem, one time I calculated I had made a mixture of 1:100 (that is double the prescribed amount of 2-T) and experienced nothing in particular that half year later. Remember, 2-Stroke engines use 1:25 - 1:50 ratio which is 8-4 times 'fattier'. Mind you, Dieselmixture can and should be : 1L 2-T on a fill of 60L Diesel I provide ALL my none-catalyst diesel- and petrolcars with 2-T. From my Peugeot 201 of 1931 to my Citroën CX Diesel 1982 and gasoline-engined BX E from 1987.

Well, I thought this problem had solved itself. The thing started well most of last year and until this week. I thought it had a stuck ring or valve, or a little bit of varnish from the modern gasoline. Anyway, I installed two champion CJ8 s, gapped to .025. And it started right off. Changing from NGK BMR4As Lot's of good comments on this thread. It's a little over my head. I'm assuming that if the composite camshaft gear breaks, it's definitely not going to run, correct? And further regarding this thing, is this gear failure always a fairly benign thing? That is nothing else gets bent or damaged when this thing goes? I had the case cover off to repair the inner gasket to prevent water from leaking into the crankcase, actually I don't think it ever went into the crankcase, but it eventually would not hold water even to mow the yard once. I then, wasn't aware of this issue with the composite gear and I'm not totally sure if it has the composite or not. I seem to remember looking at a brown fiber gear-looking thing. But I'm not sure. Thanks for all the comments, and I think it's just the spark plugs causing this problem. Although I'm not sure why long cranking worked to get it to start. Anyway...Cheers!

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