Jeff Reiter Posted February 29, 2020 Report Share Posted February 29, 2020 (edited) I recently purchased a 1962 Mooney m20c. I'm having an issue starting the airplane. It has no primer, so I'm supposed to pump the throttle once or twice before starting. But I'm having no success with that. It seems to start when I lean it halfway or completely leaned with virtually no throttle. Then other times, it will start with a 1/2 push of the throttle to prime. I haven't figured it out yet, but at least I can usually get it started now, usually takes 4-5 eight second attempts, rather than a few blades. My brother, an auto mechanic said that if the carb float stopped floating it would produce a rich, flooded condition? I deleted some info. on fuel burn which turned out to be 11.2 gallons rather than 15.4 . My apologies for the error. Any one experience this? Do I need to rebuild the carb? Edited February 29, 2020 by Jeff Reiter Correction Quote Link to comment Share on other sites More sharing options...
Huitt3106 Posted February 29, 2020 Report Share Posted February 29, 2020 The typical start procedure I use is to run the electric fuel pump until the fuel pressure maximizes then turn it off. I’ll then pump the throttle 3 to 5 times and watch the fuel pressure drop. Once I do that I push the throttle around 1/4” (once you feel friction in the cable), push the mixture to full rich and start. It usually starts pretty fast. Is this your first mooney? Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Jeff Reiter Posted February 29, 2020 Author Report Share Posted February 29, 2020 If I pump the throttle more than once it's flooded. Your procedure won't work for me..... Quote Link to comment Share on other sites More sharing options...
Jeff Reiter Posted February 29, 2020 Author Report Share Posted February 29, 2020 Yes first Mooney Quote Link to comment Share on other sites More sharing options...
Pasturepilot Posted February 29, 2020 Report Share Posted February 29, 2020 I’ll get a word in before the floodgates open with guys screaming “GET A MOONEY INSTRUCTOR!” I start it the same way I do most any other low-wing 180 horsepower lycoming. Mags and master on. Fuel pump on until pressure stabilizes, then off. Mixture rich, throttle two pumps and cracked 1/8 inch. Should start within a couple blades. Concerning your fuel flow numbers, make a lunch run somewhere so your fuel flow is stable for a while before you get too concerned. How many years and hours are on your mags since they last saw service, overhaul, or replacement? The 500 hour inspections often slip one’s attention and failures don’t always manifest themselves as running rough or a severe mag drop. Difficult starting often is an ignition problem when it sometimes seems a fuel problem. Welcome to the “owner by a Mooney” club Quote Link to comment Share on other sites More sharing options...
cferr59 Posted February 29, 2020 Report Share Posted February 29, 2020 What is the outside temperature when you are starting? Is it early in the day and is the engine cold soaked from overnight? Also, 2 hours of pattern work is not really a way of determining average fuel consumption. Do you have a fuel flow meter? Quote Link to comment Share on other sites More sharing options...
Rjfanjet Posted February 29, 2020 Report Share Posted February 29, 2020 I have a 68C. Based in SLC. When it's cold I turn the electric pump on with the mixture full rich and pump the throttle 4 times. Starts right up, just lean the mixture after checking the oil pressure. 2 pumps of the throttle on a hot start, no issues. Quote Link to comment Share on other sites More sharing options...
Huitt3106 Posted February 29, 2020 Report Share Posted February 29, 2020 Ahh, yes I forgot to address the fuel flow as well. I have a transducer that reads out to my 530W and I typically see around 17gph (from glancing memory) at full throttle on climb out. Pattern work definitely burns a good bit more fuel so the suggestion to fly somewhere to get a better baseline is a good one. I’ve never had a flooding issue with my priming method so I’m unsure what our difference may be. But if it consistently floods that quickly I would think there may be something going on, but I’m not qualified to guess beyond that. I adjust my priming on ambient air temperature (and engine temp) if it’s cold I’ll pump 4 to 5 times but if it’s really warm I may not even need one pump of the throttle. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Hank Posted February 29, 2020 Report Share Posted February 29, 2020 @Jeff Reiter, where are you based? My C is pretty easy to crank. As others, I run the fuel pump until presure stabilizes, then turn it off. Next is Mixture to Rich and pump the throttle; fuel pressure should drop at WOT and stabilize at idle on each pump. First start of the day: hangar temps 75°F or higher, two pumps, Clear Prop and turn key. Hangar temps ~45-75°F, three or four pumps, pause a couple of seconds, Clear Prop and turn key. Hangar temps 32-45°F, five pumps, wind and set clock, put on and adjust headset, Clear Prop and turn key. At or below ~40°F with no engine heat, I turn the prop through 2 or 3 revolutions [sometimes I lose count with my 3-blade prop], then get inside, Master On, run fuel pump, turn it off, pump throttle 5-6 times and occupy myself with things for a good 60 seconds before cranking. This may take two attempts. Note that I run the Fuel Pump first with throttle and mixture at minimum settings [idle and ICO], then pump the throttle with the Fuel Pump turned off. My throttle pumps are full-stroke of the control, with little pause at WOT before coming back to idle. This worked when I was hangared on the bank of the Ohio River [coldest morning start was 8°F, unheated hangar and Tanis engine heat overnight], and it works for me now in Lower Alabama. Starting with a warm engine, no Fuel Pump at all and maybe 1 pump of the throttle. If it's cold outside, I still pause to allow the fuel more time to vaporize, because warm fuel will burn immediately but cold fuel needs time, and we all know that liquid gas doesn't burn well, it's the vapor rising off of it that burns. 1 Quote Link to comment Share on other sites More sharing options...
Hank Posted February 29, 2020 Report Share Posted February 29, 2020 (edited) Oh, fuel burn. I find that pattern work uses less fuel than traveling, even though I'm Full Rich except for time on the ground. I filled up and did 4 full stop / taxi back landings as a refresher after 4 months of frequent rain and was down about 3 gallons on each side [2 patterns per tank]. The whole thing, fuel farm to hangar, took 45 minutes. My only fuel flow devices are the Red knob and the yoke clock, and on the ground I have a calibrated dipstick. I generally travel around 9 gph block time, less on longer trips, and I descend power on to make up for the slow-speed climb. Trading altitude for speed is free when you are descending! WOT / 2700 / Full Rich for takeoff; turn crosswind and back way off in throttle to level off at 1000' agl; reduce throttle and add flaps to level off at 90 mph; drop gear, tweak throttle back to start descent; turn base then final using elevator, trim to maintain glideslope, reducing throttle as needed if altitude is too high; idle throttle when the field is made; touchdown, establish rolout, pull Mixture way back to approximate taxi position; slow and exit runway, taxi back to beginning. Keeping the mixture very lean on the ground will keep the engine running happily, and minimize lead fouling in your sparkplugs. I like it so lean that taxiing uphill [or adding more than a tiny nudge of power for any reason] makes the engine stumble / run rough / try to quit unless I also move Mixture forward. This is somewhere around 1/3 of the full stroke forward. Fly safe! And tell us where you are . . . . . Edited February 29, 2020 by Hank Quote Link to comment Share on other sites More sharing options...
Jeff Reiter Posted February 29, 2020 Author Report Share Posted February 29, 2020 I just moved to Ocean Springs, MS. I have no fuel flow instruments, I just fill tanks and divide gallons by hours run. Quote Link to comment Share on other sites More sharing options...
carusoam Posted February 29, 2020 Report Share Posted February 29, 2020 There is no designed in way to flood the O360 engine with a single pump of the throttle... Is there @Hank? A typical start for my old O360 was a few pumps... after the electric pump was used to pressurize the system... Winter temps in NJ were up to 10 pumps... (no pre-heat) As the accelerator pump wears... more pumps are required. Often not enough fuel is mis-interpreted as flooding... The M20C has a nice way to show you it has been flooded... the nose tire gets bathed in 100LL... Hard to run different starting techniques... it either works or it doesn’t... then it’s warm or flooded... Be sure you are following the procedures... adding random variables makes things really hard... +1 for training with a Mooney CFI +1 for flying with other Mooney owners... +1 for taking notes over the next 10 years... you will get really good at this after a while... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
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