0TreeLemur Posted October 30, 2022 Report Posted October 30, 2022 3 hours ago, DCarlton said: The one fuel related failure mode I have swirling in my head that I worry about is.... what happens if the fuel sump drain valve doesn't seat properly and you drain both tanks in flight? I've always wondered if that is possible. During my preflight, I pull the valve, let it drain for a few seconds, push it down deliberately, and then walk around to the left side of the plane to make sure it's no longer dripping. Fuel gauges might help you spot that sort of failure before you're dry. Wondering if anyone has experience with that drain valve not reseating properly and failing open ? I've never seen the guts to know how it works. It has happened. If it happened to you, your first tank would empty fast which should alert you that something is seriously wrong. Unless you have no fuel in the second tank, you should have at least some fuel to get you to a strip, land and diagnose. 1 Quote
DXB Posted October 31, 2022 Report Posted October 31, 2022 On 10/29/2022 at 2:14 PM, ArtVandelay said: Can you elaborate? The main bug is that whenever one side momentarily reads the alarm fuel value (mine is 6 I think), the flashing low fuel indication can't be permanently silenced on that side. When the attitude of the plane raises the sender above that 6 reading and back down again, the alarm triggers over and over. This feature is an annoying distraction for me (particularly in IMC flying an approach) and also stresses out passengers. Now I try to burn any side that needs to go below 10 all the way down to 1 gallon so the alarm has no chance of resetting, then switch to the fuller tank before starting descent. But if the fuller side needed to go below 10 subsequently (generally not the case given the reserves I keep), I would end up in the same situation. I've had multiple conversations with JPI customer service by phone and at KOSH about it - the answers have been either (1) nothing can be done or (2) send it back to us again, might be able to fix - I've been reluctant to pull it again. 2 Quote
Jsno Posted November 3, 2022 Report Posted November 3, 2022 I have had my floats overhauled. They are somewhat accurate. I have installed digital in a previous airplane and through they are accurate they vary according to pitch of the aircraft. I think fuel flow is the most accurate way to determine how much fuel that you have. As far as a leaking drain, If it is well maintained a non issue. Plus you will see it on the ground during a preflight. More likely to have fuel seeps from tank seams. 2 Quote
FlyingDude Posted November 3, 2022 Report Posted November 3, 2022 I'm not a great fan of using fuel indicators to gauge level, becuase JPI fuel flow is very accurate. I find digital senders too fancy for my budget ... Other prioties. But, I fixed the broken sender to hedge against the potential issue in which one tank drains in flight, just like you mentioned above. Shortly after fixing that, right wing cap got loose and left a blue stripe on the wing. Only lost 1.5gl in 30min, so I didn't catch that with the gauge. I saw it after landing. At that rate, this much of a leak would amount to 12gl in 4 hrs. That could potentially be startling if you deplete the other tank and are flying on this tank over a long stretch without many airports. I wish they had digital senders that would work like the low fuel indicator in a car. They would warn you of such potential cases, and then you could use the good ol' calibrated stick during preflight and fuel flow indicator during flight. Quote
carusoam Posted November 4, 2022 Report Posted November 4, 2022 Summarish…. 1) Good senders don’t need to be digital… 2) Digital senders bring you from 1% accuracy down to .1% accuracy… figuratively speaking…. Both are good if working correctly… 3) 1% accuracy doesn’t show on analog gauges… 4) When upgrading to Ceis senders… know they have two outputs… old style analog, and best accuracy frequency mode… in case you don’t have an immediate plan for a digital display… 5) there are some lower cost digital displays mentioned above, a full on JPI 900 is not required…. 6) As far as accuracy goes…. FF (fuel flow) is pretty good and has all of the accuracy required…. 7) The value of the adding the digital Fuel Level system… is for the days when the FF is giving quirky information… (oops, did I remember to reset that number?) 8) fuel system leaks can cause all kinds of mis-information… air entering the system as well as fuel exiting the system… 9) Having two accurate systems measuring fuel quantities in different ways allows for error checking…. It is now possible to do some inflight analysis… 10) One system says you have burned 10gal, the other says 20gal has been used…. You now know with accuracy that 10gal has gone MIA… Sooooo… there is value to having two different systems with digital accuracy and displays… I asked the Ceis guy if this level of automatic system checking was available…. It would be a nice piece of info to have when/if it occurs… 11) JPI’s ability to handle changing from analog to Ceis fuel level sensors… older JPI900s went back to the factory for an update…. Today, newer JPI900s can be changed in the field… find the software setting… PP summary only, not my ideas… Best regards, -a- Quote
RobertGary1 Posted November 4, 2022 Report Posted November 4, 2022 I figured the factory senders worked great for 30 years the first time so I just overhauled them. They work great now. Factory senders only get a bad rep because people don’t overhaul them for 40 years. I have flown with cis gauges. They need to be kept clean. Eventually they’ll erratically stop sending and you need to clean them off. 2 Quote
carusoam Posted November 5, 2022 Report Posted November 5, 2022 16 hours ago, RobertGary1 said: I have flown with ceis gauges. They need to be kept clean. Eventually they’ll erratically stop sending and you need to clean them off. Let’s see if @fuellevel is still cruising the neighborhood… Interesting pirep regarding care and maintenance of Ceis fuel level sensors… Best regards, -a- Quote
rwabdu Posted November 5, 2022 Author Report Posted November 5, 2022 Here's the fuel tank dip stick I made a few weeks ago, pumped out the tanks and added back 5gal at a time. Hopefully this will be helpful to some of you. It is for a 1968 mooney M20c 54 gal fuel bladders (27 gal /side). There are approximately 5gal in the tanks when the dip stick registers 0. Quote
Jpravi8tor Posted November 5, 2022 Report Posted November 5, 2022 I’m still waiting to see the picture of a calibrated fuel stick for a 64 gallon F model no bladders TIA Quote
MikeOH Posted November 5, 2022 Report Posted November 5, 2022 1 hour ago, Jpravi8tor said: I’m still waiting to see the picture of a calibrated fuel stick for a 64 gallon F model no bladders TIA @Jpravi8tor Here you go (this is NOT my fuel stick and I make NO guarantees of accuracy): Quote
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