jetdriven Posted February 15, 2015 Report Posted February 15, 2015 My general philosophy is to follow the POH unless there's a compelling reason to do otherwise. Burning down my airplane would lead me to search an alternate method. Quote
xrs135 Posted February 16, 2015 Report Posted February 16, 2015 I'll typically follow the POH procedure with my C when it's cool/cold out. If I give it 4-5 pumps of throttle it will start 1/3 of the time within a couple turns. If it doesn't, I give it two more pumps before immediately trying again and then it starts right up! Quote
bonal Posted February 16, 2015 Report Posted February 16, 2015 Well as I said before my first few months of mooney ownership cold starts were a cast iron bitch. When I began doing the POH method of pumping then waiting I have never had a start take more than a few blades. Before when I would pump while cranking I would crank and crank and cuss and swear and have back fires and really bad fowled plugs and say foolish things like god I miss my Cessna. I don't know what happened to the Piper owner in that film but correct me if I'm mistaken don't pipers have primers and do we know if that fire even occurred as a result of starting. I'm going to stick with what works for me and Snoopy pump sit crank. 1 Quote
jetdriven Posted February 16, 2015 Report Posted February 16, 2015 What happened if you cranked 3 seconds while pumping the throttle, then waited the same 30 seconds? If you cowl is full of explosive vapor which gets sucked it and starts the engine, what happens when it backfires and lights that explosive mixture? Ask the OP. Quote
Guest Posted February 16, 2015 Report Posted February 16, 2015 Could one get FAA approval to install a priming system copied from another aircraft? Clarence Quote
bonal Posted February 16, 2015 Report Posted February 16, 2015 What happened if you cranked 3 seconds while pumping the throttle, then waited the same 30 seconds? If you cowl is full of explosive vapor which gets sucked it and starts the engine, what happens when it backfires and lights that explosive mixture? Ask the OP. Pulling cold un atomized fuel into the combustion chamber is a recipe for back fires . My question to those who think letting fuel vaporize in the box before cranking is if there is no fuel in the engine yet what on earth could make it backfire. Also if one waits sufficient time and does not over do it on the pumping all the fuel vaporizes then even if there was a backfire the most that would happen is a quick bang and then nothing left to burn. Quote
Mooneymite Posted February 16, 2015 Report Posted February 16, 2015 This is a very serious issue....cold starting. Happily, I have virtually no experience. My solution is not for everyone, but it has definitely worked for me (carb O-360) If the temperature in F is less than your age in years.....do not fly. My engine always starts by the second blade. 1 Quote
jetdriven Posted February 16, 2015 Report Posted February 16, 2015 Pulling cold un atomized fuel into the combustion chamber is a recipe for back fires . My question to those who think letting fuel vaporize in the box before cranking is if there is no fuel in the engine yet what on earth could make it backfire. Also if one waits sufficient time and does not over do it on the pumping all the fuel vaporizes then even if there was a backfire the most that would happen is a quick bang and then nothing left to burn. how is it a recipe for backfires? My IO-360 sometimes backfires and it is already primed, the fuel is sitting on the intake valve. Sometimes it backfires for no reason on hot starts, cold starts, flooded starts etc. It happens. I cant predict when it will, or is certain not to. What can make it backfire is when that lean vaporized mixture gets into the combustion chamber, lights off and then backfires, igniting the stuff inside the cowl. Regarding the "quick bank nothing left to burn" common maintenance procedure dictates an inspection of the entire induction system for damage. Brackett aero filters require it in their ICA. Im just trying to help crowdsource a way to start it efficiently, yet safer. Quote
bonal Posted February 16, 2015 Report Posted February 16, 2015 how is it a recipe for backfires? My IO-360 sometimes backfires and it is already primed, the fuel is sitting on the intake valve. Sometimes it backfires for no reason on hot starts, cold starts, flooded starts etc. It happens. I cant predict when it will, or is certain not to. What can make it backfire is when that lean vaporized mixture gets into the combustion chamber, lights off and then backfires, igniting the stuff inside the cowl. Regarding the "quick bank nothing left to burn" common maintenance procedure dictates an inspection of the entire induction system for damage. Brackett aero filters require it in their ICA. Im just trying to help crowdsource a way to start it efficiently, yet safer. Not trying to start an argument just stating what my before and after situation with my carburetor. Using an accelerator pump as an engine primer is not a precise method of fuel delivery and you can have a lot more fuel on the valves in the plenum in the carb that is not vaporized you mention that your IO back fires on occasion when that happens do you perform an inspection. I'll stick with what works and the procedure spelled out in my POH. Quote
Hank Posted February 16, 2015 Report Posted February 16, 2015 My C has backfired once in almost 600 hours, when I was already experiencing starting trouble, and it was a hot start. Following the procedure in my Owners Manual attached in Post #2, no problems, no backfires, nothing but a finely-running engine. 3 Quote
bonal Posted February 16, 2015 Report Posted February 16, 2015 Ah there you are Hank, these fuel injection guys have been beating me up.. Quote
Hank Posted February 16, 2015 Report Posted February 16, 2015 After all, there are as many Cs as Js, which total over half of the fleet. Just don't know why so many J owners think their procedures apply to ours. Sure would be nice to have their high, air-brake gear speeds, though. ☺️ Just not at the cost of the injected guys' hot start procedures. Our O-360's are easy to crank, hot or cold. But below freezing with no preheat available, it can be challenging; I use the same procedure, usually takes 2-3 tries, and I pray to not frost the plugs. Quote
aaronk25 Posted February 16, 2015 Report Posted February 16, 2015 Pulled one of our clubs 172s out today in mn...sure enough last guy didn't plug it in. 5f out. Hit starter shoved throttle in and out 3 times real fast ....pa pa pa bruuuuummmm. Piece of cake. Then I did the cardinal sin....I shut it down. All for you guys! Someone will fly it tomorrow...all will be fine. The other reason I don't use the primers, if avail...I always for get to lock them back forward..... Quote
Marauder Posted February 16, 2015 Report Posted February 16, 2015 If the temperature in F is less than your age in years.....do not fly. If this were true, I would need to live in southern Florida or further south! Quote
Mooneymite Posted February 16, 2015 Report Posted February 16, 2015 If this were true, I would need to live in southern Florida or further south! Yeah...we'll probably meet in some equatorial fly-in community soon. :-) Quote
par Posted February 17, 2015 Author Report Posted February 17, 2015 UPDATE: Due to the weather, my shop is still closed so I went and opened up the cowling and had a look for myself. I did not see any obvious damage besides some soot on the under side of the engine cowling where the drain is located. I also had a look behind the air filer but did not see anything that resembles fire damage. I'm hoping the mechanic can come see it tomorrow. Here are some pictures. Quote
ArtVandelay Posted February 17, 2015 Report Posted February 17, 2015 Par: I can't be sure, but is your bottom shock disc cracked? Quote
Marauder Posted February 17, 2015 Report Posted February 17, 2015 Par: I can't be sure, but is your bottom shock disc cracked? I think that is the seam on the donut. Quote
Marauder Posted February 17, 2015 Report Posted February 17, 2015 UPDATE: Due to the weather, my shop is still closed so I went and opened up the cowling and had a look for myself. I did not see any obvious damage besides some soot on the under side of the engine cowling where the drain is located. I also had a look behind the air filer but did not see anything that resembles fire damage. I'm hoping the mechanic can come see it tomorrow. Here are some pictures. You definitely have evidence of an air box fire. Hopefully nothing will be compromised and the blackening you are seeing is nothing more than smoke sediment. Quote
Guest Posted February 17, 2015 Report Posted February 17, 2015 Aside from the possible cracked nose shock disc, the fuel pressure hose looks to be in poor condition and the there appears to be a missing clamp on the air intake bellows. Clarence Quote
par Posted February 18, 2015 Author Report Posted February 18, 2015 Par: I can't be sure, but is your bottom shock disc cracked? Not cracked...it is a seam as Marauder said. Quote
par Posted February 18, 2015 Author Report Posted February 18, 2015 Aside from the possible cracked nose shock disc, the fuel pressure hose looks to be in poor condition and the there appears to be a missing clamp on the air intake bellows. Clarence Are you referring to the black hose? May I ask what exactly is in poor condition? I ask because the plane went though a through inspection/annual recently and this was not pointed out. I'll take a closer look at it tomorrow. I also was not aware that there should be a clamp there...I'll bring that up to my mechanic. Thanks. Quote
carusoam Posted February 18, 2015 Report Posted February 18, 2015 It looks like it may need the equivalent of a hose clamp to keep the bellows in place... Get a good look at the bellows as well. Age does take a toll on many of them... Without the clamp or any holes that may have formed would allow air to enter the engine by-passing the filter... Good luck with getting everything back in order. Best regards, -a- 1 Quote
Guest Posted February 18, 2015 Report Posted February 18, 2015 Are you referring to the black hose? May I ask what exactly is in poor condition? I ask because the plane went though a through inspection/annual recently and this was not pointed out. I'll take a closer look at it tomorrow. I also was not aware that there should be a clamp there...I'll bring that up to my mechanic. Thanks. In the picture it looks like there is corrosion between the hose and the aluminum sleeve. Clarence Quote
47U Posted February 21, 2015 Report Posted February 21, 2015 Picture #3... it looks like the drain hose on the bottom of the airbox is missing. There's a straight nipple welded to the bottom of the airbox towards the aft end. It points down and forward towards the grommet in the lower cowling. There should be a short piece of hose on the nipple that drains excess fuel in the airbox through the hole and onto the ramp. It prevents a fuel from accumulating inside the cowling. Your damage doesn't look too serious, though, from looking at the pictures. With a few parts, your mechanic should be able to fix you up in short order. Good luck and fly safe. 1 Quote
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