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RE: checking tillison pop off pressure - Mel Ruffner - 10-18-2017 (10-18-2017, 01:27 PM)David Luciani Wrote: doug, RE: checking tillison pop off pressure - doug tenney - 10-18-2017 Mel, I'm guessing that your fulcrum arm is too high. When that's the case, as soon as the carb is assembled, the metering diaphragm presses on the fulcrum arm, holding the inlet needle off its seat. Start the motor and the fuel pump will proceed to empty your fuel tank into your crankcase. It's also possible that your inlet needle isn't making a seal. Result is the same. If either condition exists, you'll find it immediately if you try to check the pop-off with the carb assembled. Fulcrum arm too high = no pop-off. Bad needle = carb will leak down as fast as you can pump. No, I don't believe that bad reeds would cause flooding. An engine that idles with the idle speed screw backed out all the way usually has an air leak. You need to find out if that's the case. RE: checking tillison pop off pressure - David Luciani - 10-18-2017 nope reeds can cause trouble but excess fuel would be strange. the reeds should lie flat on their flat surface with no air gap. also should be smooth on edges. not cracked or ragged. if they are not flat dis assemble and flip them. excess fuel as doug said is bad seat or diaphram issues with fulcrum. height or spring. one easy mistake is accidently reversing gasket order with diaphram , check that first. if you did the fulcrum arm will be always open from the rivit pressing on it. RE: checking tillison pop off pressure - Mel Ruffner - 10-20-2017 Another question. If you have no pop off pressure,will a carb still work ,but not real good?I can,t get no reading with the carb on my motor.I didn't,t try putting marvel oil or wd40 in my fuel hose maybe I should try that to get a reading. Thanks again for the help, I have learned so much reading and asking questions on this forum RE: checking tillison pop off pressure - Terry Sullivan - 10-20-2017 I buy tilly kits for about $3.50. Anytime I pull a carb apart, a new kit goes in. RE: checking tillison pop off pressure - doug tenney - 10-20-2017 Q. If you have no pop off pressure,will a carb still work ,but not real good? A. No. The carb basically becomes a fuel leak into the engine. It might run under some conditions, but it's sort of like that broken clock: it shows the correct time twice a day. The point of the WD-40 or Marvel oil is to cheat a bit to get a seal. After all, when the engine is running the needle doesn't need to seal AIR, it needs to seal FUEL. Even a good needle can't be expected to hold air pressure if it's dry. RE: checking tillison pop off pressure - David Luciani - 10-20-2017 WET THE NEEDLE THEN GET BACK WITH RESULTS. RE: checking tillison pop off pressure - Mel Ruffner - 10-24-2017 My tillison is a hl237a. still having trouble getting a pop off reading so I disassembled carb. My needle is plastic not brass.Would the plastic needle be harder to seat?Are all tillison needle and seats the same? Or do you need to find one for your specific carb model. Thanks again everyone RE: checking tillison pop off pressure - David Luciani - 10-25-2017 (10-24-2017, 07:54 PM)Mel Ruffner Wrote: My tillison is a hl237a. still having trouble getting a pop off reading so I disassembled carb. My needle is plastic not brass.Would the plastic needle be harder to seat?Are all tillison needle and seats the same? Or do you need to find one for your specific carb model. Thanks again everyone mel, what is the history of the carb? i think i remember sending you a carb? regardless, typically a plastic needle is white and they were used in alky modified carbs back in the day. so my experience says you have a older modified alky carb. typically i see metal needles with plastic tips on most gas carbs . but now a days they can be found in newer alky carbs as the tips are made with much better material. if you have an alky carb it will be alot harder to run on gas then a REGULAR CARB. can you post a pix of the needle? RE: checking tillison pop off pressure pics of carb and needle - Mel Ruffner - 10-25-2017 Dave here are some pics of needle. It,s white plastic. If it is a needle for alky how hard is it to switch the carb to run gas? That is what i run. |