Echo Posted July 29 Report Posted July 29 I bought four six gallon portable fuel containers. They fit in my (always in car dog crates). I fill them when I go by a cheap gas airport and dump them in when I need them. Problem solved. Quote
DCarlton Posted July 29 Report Posted July 29 So after reading the thread a few times and watching Mr Maxwells video again, the only time time you should advance the throttle wide open is when you suspect the engine is flooded? Or is the wide open throttle, mixture ICO procedure not applicable? Quote
natdm Posted July 29 Report Posted July 29 5 hours ago, C.J. said: @gwav8or Watch this video of Don Maxwell doing repetitive hot starts in a J. It should eliminate 99.99999999% of your hot start issues. Cheers, C.J. I need this for Continentals, for my K. Quote
Shadrach Posted July 29 Report Posted July 29 36 minutes ago, DCarlton said: So after reading the thread a few times and watching Mr Maxwells video again, the only time time you should advance the throttle wide open is when you suspect the engine is flooded? Or is the wide open throttle, mixture ICO procedure not applicable? The only reason I can think of to crank with the throttle wide open is when trying to evacuate fuel from fuel saturated engine. 1 Quote
Ragsf15e Posted July 29 Report Posted July 29 (edited) 16 minutes ago, Shadrach said: The only reason I can think of to crank with the throttle wide open is when trying to evacuate fuel from fuel saturated engine. Yes, i think the (relatively) standard “flooded start” is mixture cutoff, throttle full. Start cranking. Slowly pull throttle back. It takes a little while, so go slow. It will catch at some point before idle. Be ready to pull throttle back to idle and get mixture in at the same time. Helps if you have 3 arms. I don’t need to do this flooded start more than once a year or so if I really messed up everything else. But if fuel is dripping out your sniffle, it’s flooded. Its best to master normal and hot starts so you don’t get to flooded because there’s more than a zero chance of a tailpipe fire, not to mention the possible fuel dripping out the sniffle below the engine. Edited July 29 by Ragsf15e 2 Quote
Shadrach Posted July 29 Report Posted July 29 1 hour ago, Ragsf15e said: Yes, i think the (relatively) standard “flooded start” is mixture cutoff, throttle full. Start cranking. Slowly pull throttle back. It takes a little while, so go slow. It will catch at some point before idle. Be ready to pull throttle back to idle and get mixture in at the same time. Helps if you have 3 arms. I don’t need to do this flooded start more than once a year or so if I really messed up everything else. But if fuel is dripping out your sniffle, it’s flooded. Its best to master normal and hot starts so you don’t get to flooded because there’s more than a zero chance of a tailpipe fire, not to mention the possible fuel dripping out the sniffle below the engine. I have not flooded an engine in well over a decade. If I did it now, I am sure that I would likely pooch the procedure. Sometimes the best course of action is to walk away for a while if time permits. 2 Quote
gwav8or Posted July 30 Author Report Posted July 30 (edited) 20 hours ago, Shadrach said: I have not flooded an engine in well over a decade. If I did it now, I am sure that I would likely pooch the procedure. Sometimes the best course of action is to walk away for a while if time permits. So here is a weird one. After the flooding event on Sunday, I put the plane back in the hangar and waited until Monday evening. Went out on Monday evening and tried a standard start procedure and it immediately flooded again and wouldn't start. When we put it back in the hangar after almost running the battery dead, it was dripping fuel. I put the battery on a charger and it was down to 60% capacity. We'll see if it will start tonight. I plan on not touching anything and seeing if it will start. Wish the "squishy bit behind the yoke" some luck! lol Edited July 30 by gwav8or Added "squishy bit behind the yoke" description Quote
PT20J Posted July 30 Report Posted July 30 48 minutes ago, gwav8or said: So here is a weird one. After the flooding event on Sunday, I put the plane back in the hangar and waited until Monday evening. Went out on Monday evening and tried a standard start procedure and it immediately flooded again and wouldn't start. When we put it back in the hangar after almost running the battery dead, it was dripping fuel. I put the battery on a charger and it was down to 60% capacity. We'll see if it will start tonight. I plan on not touching anything and seeing if it will start. Wish the "squishy bit behind the yoke" some luck! lol When you normally prime, do you open the throttle at least 1/4 travel? If not, the idle mixture valve will greatly reduce fuel flow. If you left the throttle open after the failed flooded start attempt and then later primed it as usual a lot more fuel would flow than you were expecting if you prime for the normal amount of time. Quote
gwav8or Posted July 30 Author Report Posted July 30 11 minutes ago, PT20J said: When you normally prime, do you open the throttle at least 1/4 travel? If not, the idle mixture valve will greatly reduce fuel flow. If you left the throttle open after the failed flooded start attempt and then later primed it as usual a lot more fuel would flow than you were expecting if you prime for the normal amount of time. Yep, that's how I prime. Throttle open 1/4 mixture lean fuel pump on mixture rich for 4 seconds (starts better with 4 seconds vs 3 seconds) fuel pump off mixture lean throttle to 1000 rpm (approx) engage starter Sometimes, if it doesn't start after about 8-10 blades, I will engage the fuel pump for about a second and it starts. Quote
slowflyin Posted July 30 Report Posted July 30 Aside from all the techniques, I found keeping my mags in top shape and installing a high speed starter had a significant impact on my ability to start reliably. 2 Quote
gwav8or Posted July 30 Author Report Posted July 30 5 minutes ago, slowflyin said: Aside from all the techniques, I found keeping my mags in top shape and installing a high speed starter had a significant impact on my ability to start reliably. Yeah, I think my mags are still a couple hundred hour away from the 500 hour inspection but it would be a good idea to have them inspected, I think. I am heavily considering getting a high speed starter at annual. Quote
Ragsf15e Posted July 30 Report Posted July 30 1 hour ago, gwav8or said: Yep, that's how I prime. Throttle open 1/4 mixture lean fuel pump on mixture rich for 4 seconds (starts better with 4 seconds vs 3 seconds) fuel pump off mixture lean throttle to 1000 rpm (approx) engage starter Sometimes, if it doesn't start after about 8-10 blades, I will engage the fuel pump for about a second and it starts. I doubt this is part of your issue, but I typically prime with throttle and mixture full forward. If the throttle is back towards idle (1/4”?) the idle mixture valve limits the fuel a lot. You can see this if you have an engine monitor, watch the pressure. With the throttle back, it will build and then slowly leak down after the pump is off. If you prime with the throttle forward (even half is fine), you will barely build pressure and it falls off immediately when you turn off the pump. It’s a much more consistent prime as the fuel is flowing instead of restricted to the idle mix valve. 2 Quote
gwav8or Posted July 30 Author Report Posted July 30 35 minutes ago, Ragsf15e said: I doubt this is part of your issue, but I typically prime with throttle and mixture full forward. If the throttle is back towards idle (1/4”?) the idle mixture valve limits the fuel a lot. You can see this if you have an engine monitor, watch the pressure. With the throttle back, it will build and then slowly leak down after the pump is off. If you prime with the throttle forward (even half is fine), you will barely build pressure and it falls off immediately when you turn off the pump. It’s a much more consistent prime as the fuel is flowing instead of restricted to the idle mix valve. Yeah, I prime with the throttle 1/4 (one fourth) the way in. Quote
DCarlton Posted July 30 Report Posted July 30 2 hours ago, PT20J said: When you normally prime, do you open the throttle at least 1/4 travel? If not, the idle mixture valve will greatly reduce fuel flow. If you left the throttle open after the failed flooded start attempt and then later primed it as usual a lot more fuel would flow than you were expecting if you prime for the normal amount of time. I've been doing this since you suggested it a while back. Opening the throttle more when priming. Thanks. Quote
Shadrach Posted July 30 Report Posted July 30 3 hours ago, gwav8or said: Yep, that's how I prime. Throttle open 1/4 mixture lean fuel pump on Why turn on the pump on with the mixture lean? mixture rich for 4 seconds (starts better with 4 seconds vs 3 seconds) fuel pump off Why turn the pump off before going lean (ICO)? When the pump is shut off, fuel will follow gravity until the mixture is moved to ICO. mixture lean throttle to 1000 rpm (approx) engage starter Sometimes, if it doesn't start after about 8-10 blades, I will engage the fuel pump for about a second and it starts. I've made some notes above. I think that your procedure would benefit from some modifications and reordering of steps Try the following and see how it works: Throttle open 1/4 mixture rich fuel pump on until fuel pressure needle maxes out plus an extra few seconds (add a few more seconds in cold weather). Mixture to idle cut off fuel pump off throttle to 1000 rpm (approx) engage starter Little to no fuel is being pushed passed the flow divider and into the injector lines until until the system builds sufficient pressure (~4psi) to unseat the valve in the flow divider. I start my prime count AFTER the system has pressurized. Usually two to three seconds. Some boost pumps are healthier than others. I had to shorten my prime interval after Aeromotors rebuilt my Dukes pump. You will have to figure out what is ideal. If you hear exhaust "after fire" on start up, subtract a second or two for the next time. Also, do verify that the system holds pressure after going to idle cut off. Your previous method of shutting the pump off before going mixture lean likely allows for a loss of pressure (aft of the flow divider) in the time it takes to pull the knob to ICO. When I prime, I always ensure that I "lock" (mixture to ICO) the system at max attainable pressure before starting. This ensures that the cylinder intake manifolds have been primed and that the rest of the system is primed and ready to deliver fuel immediately upon enrichening the mixture. Will it make a huge difference? Maybe not, but It is best practice avoid "slack" in the system. My IO360 typically cold starts like someone took their finger off the prop of a Guillows balsa wood model with a double knotted rubber band. Which is to say that more often than not it fires on the first compression stroke. When it doesn't, it's usually during the transition from fall to winter when I tend to under prime on the first few cold days. Quote
Shadrach Posted July 30 Report Posted July 30 1 hour ago, Ragsf15e said: I doubt this is part of your issue, but I typically prime with throttle and mixture full forward. If the throttle is back towards idle (1/4”?) the idle mixture valve limits the fuel a lot. You can see this if you have an engine monitor, watch the pressure. With the throttle back, it will build and then slowly leak down after the pump is off. If you prime with the throttle forward (even half is fine), you will barely build pressure and it falls off immediately when you turn off the pump. It’s a much more consistent prime as the fuel is flowing instead of restricted to the idle mix valve. It does not take much throttle movement for the system to allow good fuel flow for prime. However, I too prime with both knobs forward. I try to eliminate ambiguity and create precise and repeatable procedures. It helps to eliminate guess work when trouble shooting. 2 Quote
gwav8or Posted July 30 Author Report Posted July 30 10 minutes ago, Shadrach said: I've made some notes above. I think that your procedure would benefit from some modifications and reordering of steps Try the following and see how it works: Throttle open 1/4 mixture rich fuel pump on until fuel pressure needle maxes out plus an extra few seconds (add a few more seconds in cold weather). Mixture to idle cut off fuel pump off throttle to 1000 rpm (approx) engage starter Little to no fuel is being pushed passed the flow divider and into the injector lines until utill the system builds at least 14psi. I start my prime count AFTER the system has fully pressurized. Usually two to three seconds. Some boost pumps are healthier than others. I had to shorten my prime interval after Aeromoters rebuilt my Dukes pump. You will have to figure out what is ideal. If you hear exhaust "afterfire" on start up, subtract a second or two the next time. Also, do verify that the system holds pressure after going to idle cut off. Your previous method of shutting the pump off before going mixture lean likely allows for a loss of pressure in the time it takes to pull the knob to ICO. When I prime, I always ensure that I "lock" (mixture to ICO) the system at max attainable pressure before starting. This ensures that the cylinder intake manifolds have been primed and the rest of the system is primed and ready to deliver fuel immediately upon enrichening the mixture. Will it make a huge difference? Maybe not, but It is best practice avoid "slack" in the system. My IO360 typically cold starts like someone took their finger off the prop of Guillows model with a double knotted rubber band. Which is to say that more often than not it fires on the first compression stroke. When it doesn't, it's usually during the transition from fall to winter when I tend to under prime on the first few cold days. Honestly, I was just following the procedure that the previous owner show me that he said worked for him I will adjust my procedure as noted above. Much appreciated! Quote
Shadrach Posted July 30 Report Posted July 30 14 minutes ago, gwav8or said: Honestly, I was just following the procedure that the previous owner show me that he said worked for him I will adjust my procedure as noted above. Much appreciated! Understood... I have spent too much time reading the Precision Aeromotive training manual and have sort of developed my procedure based on my understanding of how the system functions. There are more than a few ways to skin this cat. Just sharing mine. The POH (see below) does suggest to go to ICO before turning the pump off. 10. Turn boost pump on and note fuel pressure indication. 11. Move mixture to full rich (forward) position for three seconds and return to idle cut- off (aft). Do not keep the mixture control in the full rich position more than a few seconds with the boost pump on to avoid flooding the engine 1 Quote
gwav8or Posted July 31 Author Report Posted July 31 Went to the airport last night to fly. Left mixture at ICO, throttle at ~1000 RPM, hit the starter and it fired right up. However, as I pulled it out of the hangar, I noticed fuel dripping from the "sniffle". I assume the tube protruding through the bottom of the cowling that was dripping fuel was connected to the sniffle? Not sure about that. I didn't notice the fuel dripping until I stopped pulling the plane out of the hangar. So, I'm guessing it was essentially still flooded? How can that be after sitting for 24 hours? Or what other possible locations was the fuel dripping from? Quote
Ragsf15e Posted July 31 Report Posted July 31 (edited) 7 minutes ago, gwav8or said: Went to the airport last night to fly. Left mixture at ICO, throttle at ~1000 RPM, hit the starter and it fired right up. However, as I pulled it out of the hangar, I noticed fuel dripping from the "sniffle". I assume the tube protruding through the bottom of the cowling that was dripping fuel was connected to the sniffle? Not sure about that. I didn't notice the fuel dripping until I stopped pulling the plane out of the hangar. So, I'm guessing it was essentially still flooded? How can that be after sitting for 24 hours? Or what other possible locations was the fuel dripping from? After shutting down a few drips of fuel is relatively normal. When it’s flooded, it’s much more like constant drip. Need to be careful though, there are two drain tubes there. One is connected to the sniffle at the bottom of the intake (right on bottom of the engine). One is connected to the fuel pump (mechanical one, back of engine). The fuel pump can also leak fuel there and that’s something to notice as it indicates a problem with the pump (it can also leak oil). So take off the side cowl and look closely at those two drains. Edited July 31 by Ragsf15e 1 Quote
gwav8or Posted July 31 Author Report Posted July 31 11 minutes ago, Ragsf15e said: After shutting down a few drips of fuel is relatively normal. When it’s flooded, it’s much more like constant drip. Need to be careful though, there are two drain tubes there. One is connected to the sniffle at the bottom of the intake (right on bottom of the engine). One is connected to the fuel pump (mechanical one, back of engine). The fuel pump can also leak fuel there and that’s something to notice as it indicates a problem with the pump (it can also leak oil). So take off the side cowl and look closely at those two drains. I will check it out. Thanks! Quote
EricJ Posted July 31 Report Posted July 31 20 minutes ago, gwav8or said: Went to the airport last night to fly. Left mixture at ICO, throttle at ~1000 RPM, hit the starter and it fired right up. However, as I pulled it out of the hangar, I noticed fuel dripping from the "sniffle". I assume the tube protruding through the bottom of the cowling that was dripping fuel was connected to the sniffle? Not sure about that. I didn't notice the fuel dripping until I stopped pulling the plane out of the hangar. So, I'm guessing it was essentially still flooded? How can that be after sitting for 24 hours? Or what other possible locations was the fuel dripping from? It's good to familiarize yourself with the various drains around the cowl bottom. You may have one for the sniffle, and there should also be one there for the fuel pump, that drips either oil or fuel if either of the diaphragms starts to fail. Further back there's another spot that may drip fuel if the boost pump starts to fail. So knowing which is which is useful. A little fuel coming out of the sniffle drain isn't a big deal, but if it is coming out of either of the fuel pump drains it's an issue. 1 Quote
MikeOH Posted July 31 Report Posted July 31 @gwav8or If I understand correctly, you started right up with NO prime and mixture at ICO? This, after noticing fuel dripping when you pulled the plane out? If so, I'm beginning to think something else may be going on if the plane had been sitting for 24 hours. No way my plane would cold start with no prime and mixture at ICO. 1 Quote
gwav8or Posted July 31 Author Report Posted July 31 31 minutes ago, MikeOH said: @gwav8or If I understand correctly, you started right up with NO prime and mixture at ICO? This, after noticing fuel dripping when you pulled the plane out? If so, I'm beginning to think something else may be going on if the plane had been sitting for 24 hours. No way my plane would cold start with no prime and mixture at ICO. Yep that's correct. The dripping started when I brought the plane to a stop after pulling it out of the hangar by hand. I sure hope there's nothing bad going on. I'm working on Commercial and am only 3 hours away from being checkride ready. CFI says I'm ready now. All I need right now is to put the plane in the shop for a week..... Quote
MikeOH Posted July 31 Report Posted July 31 I have no idea how long fuel can stay in the intake after flooding, or if there are areas that it can pool, and then 'slosh' out and drain out the sniffle when the plane is moved. I would have thought 24 hours would be enough time for it to evaporate, but I don't really know. Did you notice any fuel dripping AFTER your flight last night? Use the same no prime, mixture ICO, on your next cold start. It should be interesting to see if it starts right up, or not! Quote
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