jetdriven Posted May 7, 2014 Report Share Posted May 7, 2014 ON the MAPA list today another M20J owner had the fuel line break behind the instrument panel and dump avgas all over the inside of his plane. Earlier this year it happened to another MAPA list pilot. It also happened to my lawyer a few years back on his M20F. This hose runs from the firewall to the fuel pressure gauge. Starting in 1978 (24-0377) Mooney replaced this fuel line in the cockpit with an electric gauge with the transducer mounted forward of the firewall. Older airplanes have this hose to a mechanical fuel pressure gauge. Its not an "on condition" hose like the teflon hoses. Some of these hoses are approaching 50 years in service. Curiously, they kept the nearly the same 45" long hose from the fuel servo to the transducer, rather than mount the transducer on or near the servo. P/N is 156003-3S-0210, or basically, a -3 braided hose with straight ends on it, 21" long. I got mine from Guy Ginbey for 110$, PHT is the same. I checked the date on ours, its 1982. New one is sitting in a box to be put on when I get home again. Please check the PT date on your hose before it happens to you. (text from MAPA list) Well that was lovely. The fuel line to the pressure gauge in our M20J (or maybe the gauge itself) failed dripping/pouring a large amount of fuel onto the copilot and carpet. We were climbing through about 2,000' on the way to Palo Alto having just completed a practice ILS into Livermore. Needless to say, we declared an emergency and got on the ground in Livermore as soon as we could, but I was sure watching that fuel drip/leak and hoping (a lot!) that there were no sources of spark anywhere around! Fortunately winds were light (although directly across the runway) in Livermore tonight, unlike almost every other airport around. Quote Link to comment Share on other sites More sharing options...
rahill Posted May 7, 2014 Report Share Posted May 7, 2014 Yeah, that was me. The short term fix is to replace that fuel line (it is a hole in the line, not the gauge). Longer term fix may be to replace the gauge with a remote transducer version, assuming that's possible. Rich Quote Link to comment Share on other sites More sharing options...
jetdriven Posted May 7, 2014 Author Report Share Posted May 7, 2014 Rick, the factory mounted a transducer in front of the firewall and put the fuel pressure gauge in the instrument cluster. It replaced the Ammeter, which went to its own separate guage. then you have the single needle manifold pressure gauge too. Im not sure the solution, except a new hose every 30 years or so How much gas leaked in your plane, BTW? Quote Link to comment Share on other sites More sharing options...
orionflt Posted May 7, 2014 Report Share Posted May 7, 2014 My C model had an actual hard line with flared fittings on it from the factory, when I removed it this past yr for a MVP-50 upgrade I inspected it and it was in surprisingly good shape as was the oil line which has the same type of setup. Brian Quote Link to comment Share on other sites More sharing options...
mooniac15u Posted May 7, 2014 Report Share Posted May 7, 2014 My C model had an actual hard line with flared fittings on it from the factory, when I removed it this past yr for a MVP-50 upgrade I inspected it and it was in surprisingly good shape as was the oil line which has the same type of setup. Brian My M20D had the same hard line. It developed a leak after some avionics work. It appeared that they had bent the line out of the way which kinked the line and lead to a crack. Jeff Quote Link to comment Share on other sites More sharing options...
BobAustin Posted May 7, 2014 Report Share Posted May 7, 2014 Bent oil line after avionics work sent oil over my feet in the Cessna 340 I used to own. Replaced oil and fuel lines with remote sensors. Quote Link to comment Share on other sites More sharing options...
Marauder Posted May 7, 2014 Report Share Posted May 7, 2014 Yeah, that was me. The short term fix is to replace that fuel line (it is a hole in the line, not the gauge). Longer term fix may be to replace the gauge with a remote transducer version, assuming that's possible. Rich I went the EI fuel totalizer path. Eliminated the hose and gave me fuel flow with pressure. Quote Link to comment Share on other sites More sharing options...
testwest Posted May 7, 2014 Report Share Posted May 7, 2014 I had this happen in our 1977 M20J! Was taxiing out and suddenly smelled a strong avgas odor. Realizing quickly that processed burritos do not have that type of smell, I stopped and pulled the mixture. Then I unbuckled the seat belt, got most of the way out the door and reached over and shut off the master while holding a fire extinguisher in the other hand. Luckily, no Kaboom. The ADF tray corner had worn a hole in the fuel pressure sense line behind the right avionics stack. Replaced the fuel pressure and engine cluster gages with an EDM-930. I also have a scar on my leg from an oil sense line break in a homebuilt which dripped hot oil on my leg. No fuel or oil lines behind the instrument panel, thankyouverymuch. Quote Link to comment Share on other sites More sharing options...
75_M20F Posted December 5, 2020 Report Share Posted December 5, 2020 (edited) On 5/7/2014 at 1:08 PM, jetdriven said: ON the MAPA list today another M20J owner had the fuel line break behind the instrument panel and dump avgas all over the inside of his plane. Earlier this year it happened to another MAPA list pilot. It also happened to my lawyer a few years back on his M20F. This hose runs from the firewall to the fuel pressure gauge. Starting in 1978 (24-0377) Mooney replaced this fuel line in the cockpit with an electric gauge with the transducer mounted forward of the firewall. Older airplanes have this hose to a mechanical fuel pressure gauge. Its not an "on condition" hose like the teflon hoses. Some of these hoses are approaching 50 years in service. Curiously, they kept the nearly the same 45" long hose from the fuel servo to the transducer, rather than mount the transducer on or near the servo. P/N is 156003-3S-0210, or basically, a -3 braided hose with straight ends on it, 21" long. I got mine from Guy Ginbey for 110$, PHT is the same. I checked the date on ours, its 1982. New one is sitting in a box to be put on when I get home again. Please check the PT date on your hose before it happens to you. (text from MAPA list) Well that was lovely. The fuel line to the pressure gauge in our M20J (or maybe the gauge itself) failed dripping/pouring a large amount of fuel onto the copilot and carpet. We were climbing through about 2,000' on the way to Palo Alto having just completed a practice ILS into Livermore. Needless to say, we declared an emergency and got on the ground in Livermore as soon as we could, but I was sure watching that fuel drip/leak and hoping (a lot!) that there were no sources of spark anywhere around! Fortunately winds were light (although directly across the runway) in Livermore tonight, unlike almost every other airport around. How do you read the date of manufacture on the data tag of these hoses? I just pulled mine and it says" 156003-3S-0210 1500 PSI A4Q74 PT/A/06827 660157-501 4Q74" Can you interpret? Thanks Edited December 5, 2020 by 75_M20F Quote Link to comment Share on other sites More sharing options...
Andy95W Posted December 5, 2020 Report Share Posted December 5, 2020 Manufactured 4th Quarter 1974 (4Q74) 1 Quote Link to comment Share on other sites More sharing options...
75_M20F Posted December 5, 2020 Report Share Posted December 5, 2020 (edited) Just now, Andy95W said: Manufactured 4th Quarter 1974 (4Q74) OK, that's scary! I guess its time for a new hose! Edited December 5, 2020 by 75_M20F Quote Link to comment Share on other sites More sharing options...
drapo Posted December 5, 2020 Report Share Posted December 5, 2020 Aerospace Logic manufactures a whole line of fully PMA'd and STC digital instruments to replace the old analogic ones including this MP/FP combo: http://www.aerospacelogic.com/index.php?dispatch=products.view&product_id=106 I went that way to replace most of the engine cluster instruments and next in line will be the MP/FP combo. Quote Link to comment Share on other sites More sharing options...
RobertGary1 Posted December 5, 2020 Report Share Posted December 5, 2020 Any Intel on what types of lines failed? Were these braided lines, basic Autozone rubber hose, steel lines?? -Robert Quote Link to comment Share on other sites More sharing options...
carusoam Posted December 5, 2020 Report Share Posted December 5, 2020 3 hours ago, 75_M20F said: OK, that's scary! I guess its time for a new hose! people are opting for remote sensors... Hot oil, and fuel are not welcomed to have leaking in the cabin... I lost an MP line, and an RPM line once... the subtle hint of what else could go wrong... as things were failing with wear and age... (65 M20C) There is no way to turn these off when they start leaking at altitude... Back in the day...we didn’t have choices... Today, we have quite a few... EI, JPI, and others... EI makes some small individual gauges that are very cost affective... Consider the alternatives for safety reasons... put the sensor close to the source, run the wires into the cabin... PP thoughts only, not a mechanic... of course my ship doesn’t even have a FuelP gauge... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
RobertGary1 Posted December 5, 2020 Report Share Posted December 5, 2020 While you’re at it look at the age of all your hoses. Hydraulic brake line, wing root rubber fuel hose etc. I’ve gone through and replaced most all rubber hoses now. -Robert 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted December 6, 2020 Report Share Posted December 6, 2020 Hydraulic hoses for brakes and flaps definitely don’t last 50years... But replacement of them makes sense... they aren’t hot, or super flammable... But there are small rubber hose pieces connecting the fuel lines to the fuel tanks... if you haven’t seen them expect to swap them out as well... they are not under pressure, but the original tube pieces were not very fuel resistant... These get changed out when inspecting the fuel level sensor seals... they are within a few inches of each other... So... when changing out rubber tubing made in the 60s and 70s look for their modern counterparts when able... PP thoughts only, Best regards, -a- Quote Link to comment Share on other sites More sharing options...
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