MooneyBall Posted September 27, 2022 Report Share Posted September 27, 2022 I have a 1964 M20D that was converted to a C. It recently failed to start. After turning on the master switch and putting in the mixture, I went to turn the key. All the power immediately cut off. Sometimes cycling the master switch would help restore the power. Sometimes it wouldn’t. I was advised to check the solenoids. I tapped the outter solenoid and the plane’s power was restored. But it still would cut off when trying to turn the key. Thanks to a previous post I found a part number for a solenoid. I ordered it from aircraft spruce. Upon further examination though, and reviewing photos from previous posts, I noticed that the part I ordered more closely resembles the inner solenoid. I was wondering if anyone could help me find a part number for the outter solenoid. I would also love to hear from anyone who has dealt with an airplane that has two solenoids that look like mine do, versus the ones where I just see one lonely solenoid in some of the previous posts. Thanks Quote Link to comment Share on other sites More sharing options...
David Lloyd Posted September 28, 2022 Report Share Posted September 28, 2022 Your description of the problem does sound as though the master solenoid is the problem. You have the correct PMA replacement. The “inner” solenoid is the starter solenoid. You really need to replace the cable from master to starter or at least, put a boot on it. Oddly enough, I have both to replace in the next week or so. Quote Link to comment Share on other sites More sharing options...
MooneyBall Posted September 28, 2022 Author Report Share Posted September 28, 2022 23 minutes ago, David Lloyd said: Your description of the problem does sound as though the master solenoid is the problem. You have the correct PMA replacement. The “inner” solenoid is the starter solenoid. You really need to replace the cable from master to starter or at least, put a boot on it. Oddly enough, I have both to replace in the next week or so. Thanks! If you happen upon a part number for that cable please let me know. I’m finding that identifying which part is correct is the hardest part about working on this plane. I did just notice that the outter solenoid (master solenoid? Starter relay?) had a part number on it so I was able to order a used one. The new one was out of stock and also $100 more. The part number was 6041H105A. Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 28, 2022 Report Share Posted September 28, 2022 2 hours ago, MooneyBall said: Thanks! If you happen upon a part number for that cable please let me know. I’m finding that identifying which part is correct is the hardest part about working on this plane. I did just notice that the outter solenoid (master solenoid? Starter relay?) had a part number on it so I was able to order a used one. The new one was out of stock and also $100 more. The part number was 6041H105A. Let’s make this easy… Older Mooneys only have a few relays… 1) The Master relay supplies power continuously… 2) The starter relay only supplies power when the key is pushed to start… 3) You have an M20D, call it a C if you want… electrically they are identical… 4) You own a certified plane… doing this work is best when you have a mechanic working with you… 5) Parts details are found in the parts manual… find the download section and get one… 6) Buying relays can be a challenge… in the current supply chain environment… 7) The best way to buy a part for your Mooney… call Dan at Lasar… 8) Tell Dan, what you have, and what you are looking for… 9) When you get it… hand it to your mechanic and have him install it… 10) It should be an off the shelf type item… 11) Expect part numbers have a trail of detail for newer designs, that replace the old part numbers… nobody uses 60s technology to build a relay anymore… so the part number gets changed… (rules of modern manufacturing) Just know… relays last about 40 years before they misbehave… when they do… they can leave you stranded… buying a used one because you found one on EBay… sounds like a “please strand me again” kind of plan… Now for the real challenge… see if I understood this correctly… 1) You went to start the plane… 2) All of the electricity turned off…? 3) That may not be a relay problem… 4) Did you test the relay and it failed? 5) If you are guessing the relay failed, and are replacing it… 6) This is what plane owners call parts swapping… You are close… almost there… Why did the master relay stop delivering power, when the starter was turned on… is the battery dead, or not delivering power? PP thoughts only, not a mechanic… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MooneyBall Posted September 28, 2022 Author Report Share Posted September 28, 2022 23 minutes ago, carusoam said: Let’s make this easy… Older Mooneys only have a few relays… 1) The Master relay supplies power continuously… 2) The starter relay only supplies power when the key is pushed to start… 3) You have an M20D, call it a C if you want… electrically they are identical… 4) You own a certified plane… doing this work is best when you have a mechanic working with you… 5) Parts details are found in the parts manual… find the download section and get one… 6) Buying relays can be a challenge… in the current supply chain environment… 7) The best way to buy a part for your Mooney… call Dan at Lasar… 8) Tell Dan, what you have, and what you are looking for… 9) When you get it… hand it to your mechanic and have him install it… 10) It should be an off the shelf type item… 11) Expect part numbers have a trail of detail for newer designs, that replace the old part numbers… nobody uses 60s technology to build a relay anymore… so the part number gets changed… (rules of modern manufacturing) Just know… relays last about 40 years before they misbehave… when they do… they can leave you stranded… buying a used one because you found one on EBay… sounds like a “please strand me again” kind of plan… Now for the real challenge… see if I understood this correctly… 1) You went to start the plane… 2) All of the electricity turned off…? 3) That may not be a relay problem… 4) Did you test the relay and it failed? 5) If you are guessing the relay failed, and are replacing it… 6) This is what plane owners call parts swapping… You are close… almost there… Why did the master relay stop delivering power, when the starter was turned on… is the battery dead, or not delivering power? PP thoughts only, not a mechanic… Best regards, -a- I appreciate the feedback and the tips about Dan and the parts manual. I did leave the battery charging for a while before even bothering looking elsewhere. As for power when starting, the master switch was definitely on when trying to start and definitely not left on overnight. And yes, I’ll be inviting a real mechanic out to help with the install. Again thanks for the feedback! 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 28, 2022 Report Share Posted September 28, 2022 What battery do you have, and how old is it? It sounds like it may have aged out… And when you put a load on it… it couldn’t keep up… If the brand name says Gill and it’s more than two years old… There is a capacity test to see how healthy it is… Mechanics often do this test at annual… at least when asked… Relays really behave funny when they can’t get the right voltage… Still only a PP, not a mechanic… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MooneyBall Posted September 28, 2022 Author Report Share Posted September 28, 2022 6 minutes ago, carusoam said: What battery do you have, and how old is it? It sounds like it may have aged out… And when you put a load on it… it couldn’t keep up… If the brand name says Gill and it’s more than two years old… There is a capacity test to see how healthy it is… Mechanics often do this test at annual… at least when asked… Relays really behave funny when they can’t get the right voltage… Still only a PP, not a mechanic… Best regards, -a- It’s a Concorde battery. I haven’t replaced it since I bought the plane about one year ago, and I very much doubt the previous owner replaced it in recent years based on the boat load of other issues I’ve experienced with the plane so far. I’ll definitely have them check that at annual which happens to be due in… 3 days! I was going to ask the mechanic who is doing the annual to help put in the solenoid and relay before flying it over. Feel like I should start browsing for batteries just in case.. Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 28, 2022 Report Share Posted September 28, 2022 The logs will indicate how old the Concorde is… If it has six years on it… it may be dead. They have a tendency to stop taking a good charge after a while… What other issues have you been fighting with? First year of ownership can be a drag… Once all of the parts have been replaced… you get about a decade before they need to be replaced again… Welcome to the club! Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MooneyBall Posted September 28, 2022 Author Report Share Posted September 28, 2022 10 minutes ago, carusoam said: The logs will indicate how old the Concorde is… If it has six years on it… it may be dead. They have a tendency to stop taking a good charge after a while… What other issues have you been fighting with? First year of ownership can be a drag… Once all of the parts have been replaced… you get about a decade before they need to be replaced again… Welcome to the club! Best regards, -a- Major issues have been a broken motor mount, might have a bit of a fuel leak, definitely leaking some oil, and the transponder needed to be replaced. Front tire needed a new tube, as well as a piece that reduces nose gear wobble. It’s been rough. 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 28, 2022 Report Share Posted September 28, 2022 Fortunately, there is MS… My M20C experience started a decade before MS… I owned the most worn out M20C on the planet… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Greg Ellis Posted September 28, 2022 Report Share Posted September 28, 2022 8 hours ago, carusoam said: Fortunately, there is MS… My M20C experience started a decade before MS… I owned the most worn out M20C on the planet… Best regards, -a- Not to hijack this thread but do you have any photos of this "worn out M20C" I would love to see what Mooney brought @carusoam into the Mooney fold. 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 29, 2022 Report Share Posted September 29, 2022 15 hours ago, Greg Ellis said: Not to hijack this thread but do you have any photos of this "worn out M20C" I would love to see what Mooney brought @carusoam into the Mooney fold. It was a 1965 M20C… That lived outdoors it’s entire life… it had sat for a couple of years before I bought it… It stuck a valve during my transition training… valve stuck, crashed, bent… no engine monitor… Its original paint got thinner each time I washed it…. It was barely IFR capable…. One VOR… My early IFR training went on hold…. Until the steel cage could get degaussed… The compass would hold up until it built up a break out force and start turning again… impossible to follow… Its flap return hoses cracked open… Its fuel lines and fuel level indicator rubber and cork bits leaked…. Into the cabin… oil return lines from the cylinder heads all needed to be updated… Essentially, everything that could wear was worn… before I bought it…. If it could leak, it did… The interior fabric parts were original with a fresh blue tint matching the rug… Corrosion… in a few places, one serious place…. All caught in time… flap pump seals… leaked… Every system she had… needed attention… She is still flying out west somewhere… She got a new paint scheme… I would never recognized her if I saw here… Lots of hands on, owner assisted annuals, for a machine that wasn’t so well loved before…. Oddly… she flew incredibly straight… in smooth air when well balanced fuel wise… Fond memories of the old girl! Tough decision… update or replace…? We went to get the same thing only more modern…. Fully IFR capable… started hunting the M20Js…. Best regards, -a- 1 1 Quote Link to comment Share on other sites More sharing options...
0TreeLemur Posted September 29, 2022 Report Share Posted September 29, 2022 Back to original thread. I had a similar issue a couple of years ago. I disassembled and cleaned all the contacts on the solenoid and applied some dielectric grease, and viola! problem solved. Before trying that I was so certain that the solenoid had died that I ordered a new one. Still have it. In a box. 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted September 29, 2022 Report Share Posted September 29, 2022 +1 for the magic of dielectric grease… It can keep a fine layer of oxidation from forming where you don’t want it to form… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
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