Oldmooney Posted January 30, 2017 Report Posted January 30, 2017 I have a 65 C that has all of a sudden gotten harder to start. Cold start.....boost pump on then off after pressure comes up. Pump throttle 3 times with mixture out. Then turn key. Usually it would start within 3 revolutions. As soon as it fires, I push mixture in. Lately, 3pumps as usual, no start. Repeat, no start. Push mixture in and while starting, pump about 3 more times before it starts. At oil change and visual inspection, I noticed some fuel stain on the cowl flap on the pilot side. Figured if fuel gets out, there also has to be an air leak. It came from the rubber section on the intake tubes. Had them all replaced with new and with new clamps and new gaskets. Still having the same issue starting. Any ideas? Hot starts is similar. Sent from my SAMSUNG-SM-G928A using Tapatalk
Mooneymite Posted January 30, 2017 Report Posted January 30, 2017 Anytime I hear about a C that's hard to start, I figure it's the shower of sparks. The O-360 is a very easy starting engine as long as it has fuel, air and.....sparks! I experienced this early on in my C ownership. The shower of sparks is very reliable, but it has a condenser and a set of points.....when the condenser goes bad, the points burn and the easy starting O-360 is a bear to start. Good news: the parts are very cheap and the fix is easy. Bad news: it may not be the cause. http://www.donmaxwell.com/publications/MAPA_TEXT/Shower of Sparks/Shower of Sparks.htm 2
Jerry 5TJ Posted January 30, 2017 Report Posted January 30, 2017 (edited) My 65C got progressively harder to start one fall. I figured cooler weather might be a factor. Some days it was virtually impossible to get running. After one such morning, I got it running, taxied to the runway and found the L mag was almost totally dead. After overhaul of both magnetos the plane again started up easily. The o-360 engine is started on the left mag only with shower of sparks. Edited January 30, 2017 by Jerry 5TJ Spell 1
neilpilot Posted January 31, 2017 Report Posted January 31, 2017 1 hour ago, Oldmooney said: I have a 65 C that has all of a sudden gotten harder to start. Cold start.....boost pump on then off after pressure comes up. Pump throttle 3 times with mixture out. Then turn key. Usually it would start within 3 revolutions. As soon as it fires, I push mixture in. I was surprised by your start procedure. You start with boost pump off and mixture leaned? We start our 65C by the book (POH). Mixture full forward, boost pump on, pump throttle 2-3 times (maybe 4 times if its really cold), then engage starter. 1
Skates97 Posted January 31, 2017 Report Posted January 31, 2017 18 minutes ago, neilpilot said: I was surprised by your start procedure. You start with boost pump off and mixture leaned? We start our 65C by the book (POH). Mixture full forward, boost pump on, pump throttle 2-3 times (maybe 4 times if its really cold), then engage starter. I start my 65D the same way as neilpilot and works well. When all else fails, read the directions (POH). 1
salty Posted January 31, 2017 Report Posted January 31, 2017 41 minutes ago, Skates97 said: I start my 65D the same way as neilpilot and works well. When all else fails, read the directions (POH). Me three. I'm struggling to understand the purpose behind pumping the throttle with the mixture off. 1
Oldmooney Posted January 31, 2017 Author Report Posted January 31, 2017 I know it sounds crazy. It's basically the hot start for the io360, but always starts a lot quicker that way hot or cold. Sent from my SAMSUNG-SM-G928A using Tapatalk
neilpilot Posted January 31, 2017 Report Posted January 31, 2017 3 minutes ago, Oldmooney said: I know it sounds crazy. It's basically the hot start for the io360, but always starts a lot quicker that way hot or cold. Sent from my SAMSUNG-SM-G928A using Tapatalk I owned a 64E for 2000 hours, and the IO360 is a world of difference. Give the POH O360 start procedure a try. 1
Oldmooney Posted January 31, 2017 Author Report Posted January 31, 2017 Will try againSent from my SAMSUNG-SM-G928A using Tapatalk
Raptor05121 Posted January 31, 2017 Report Posted January 31, 2017 My aux fuel pump is going out (only giving me 2psi by itself) so that is one reason mine is getting harder to start. But yes. Pump on, mixture full in, get pressure and pump the throttle. hit the ignition
Hank Posted January 31, 2017 Report Posted January 31, 2017 Hmmm . . . I run the pump to build pressure first. THEN Mixture Rich, pump the throttle and start. Two pumps if the weather is warm, and 3-5 when it's cold. Preheating in cold weather helps, but still give it extra pumps. After each pump, watch for the fuel pressure to drop a little bit, so you know that fuel is going into the carb. Another cold weather cranking trick: after you pump the throttle, wind and set the clock then put on and adjust your headset. The aim is to allow the gas you just pumped into the carb time to vaporize, which is much slower when cold, so don't do this quickly. Then crank! 3
carusoam Posted January 31, 2017 Report Posted January 31, 2017 (edited) Old Mooney, How long have you had the M20C? Where are you at? How suddenly has it gotten cold where you are? I think you are not following a good start procedure is what everyone is telling you... Selecting your own start procedure with the logic that it works for a different (fuel injected) engine will require you to learn how to make adjustments like nobody else... - test pilot The first question that I would be asking was what was the temperature of the plane that day... Since the start procedure is incredibly sensitive to OAT it is is normal to mention that as well. 100LL is the reason for this challenge. Since it is probably below 40°F outside it is common to use a form of pre heat. This is a method of getting fuel to vaporize enough to start the engine. An engine running requires fuel, air and spark. To start the engine it requires ignition timing and vaporization temperature added to the big three... The O360 has the shower of sparks that does a masterful job of making adjustments to timing for the ignition process. It also adjust the second mag to sit out during the start procedure... 1) Why not use the usual O360 start procedure? 2) Why not use preheat? 3) How long has it been since the mags got OH'd? 4) Is there any notes in the logs about the SOS being OH'd? 5) My C got none of this luxurious treatment. Until the temps got to 20°F. 6) not using preheat requires a lot of pumps of the throttle to get enough vaporization to happen. The challenge of this method is the excess fuel drains out on the main tire. You are noticing fuel drips on the cowl flaps, there is probably a lot more on the tire. Recognize the fire risk associated with this. Have Plan B in mind... 7) want to pick a goofier start procedure? use the one for the IO550. No preheat required until it's really cold, just not a good idea... It is fun being an M20C owner. Great Mooney speeds. Great Mooney efficiency. More knowledge required to get the most of what the plane has to offer. If you update your avatar, people can help you better. Best regards, -a- Edited January 31, 2017 by carusoam
flyhigh603 Posted February 1, 2017 Report Posted February 1, 2017 My C got very hard to start last 4 flights . Put her into annual and discovered my tank sealant disintegrated so bad it clogged up the primer jet. We talked in detail about my plane having to get bladders installed. Have your Mech inspect the primer jet
neilpilot Posted February 1, 2017 Report Posted February 1, 2017 Just now, flyhigh603 said: Have your Mech inspect the primer jet If I were the OP I'd try the POH start sequence before looking elsewhere 4
Oldmooney Posted April 10, 2017 Author Report Posted April 10, 2017 Ended up with something loose in the SOS and a bad plug on the left mag side. Battery was getting weak, so was replaced also. It was a 5 yr old Gill. Starts like it's supposed to now!Sent from my SAMSUNG-SM-G928A using Tapatalk 2
carusoam Posted April 10, 2017 Report Posted April 10, 2017 Nice follow-up oldM. No engine monitor, yet? Best regards, -a-
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