Newowner Posted October 2, 2019 Report Posted October 2, 2019 Anybody know location of that solenoid on 1967 M20F. Thanks in advance. Sent from my iPhone using Tapatalk Quote
carusoam Posted October 2, 2019 Report Posted October 2, 2019 Sounds like a type of solenoid newguy.... What is it attached to? What’s not working? Starter solenoid? No... not continuous master solenoid? Could be... avionics solenoid? sure... Battery one or battery two solenoid? Yeah, why not.... We have a few solenoids... in our birds. Best regards, -a- Quote
Newowner Posted October 2, 2019 Author Report Posted October 2, 2019 Meant battery solenoid. One that comes on when you turn master on. Sent from my iPhone using Tapatalk Quote
carusoam Posted October 2, 2019 Report Posted October 2, 2019 Check near the battery ... Laws of physics usually puts them close to the battery... Is your battery in the tail, or on the firewall? Call it the Master solenoid.... it operates with the Master switch... simplifies what you are looking for... When you get a chance.... put some data near your avatar... sometimes, phone users don’t know this set of data actually exists. Best regards, -a- Quote
Newowner Posted October 2, 2019 Author Report Posted October 2, 2019 Carusoam, why so much criticism and so many words??? But thanks anyways. I got it. Near the battery. Sent from my iPhone using Tapatalk Quote
carusoam Posted October 2, 2019 Report Posted October 2, 2019 Sorry new guy... Just trying to be helpful... I only know one way... it includes a lot of words, and questions... That wasn’t criticism... at least not the way I wrote it... I see your point. Watch me get better at writing... You should see how far I have come... Best regards, -a- Quote
Newowner Posted October 2, 2019 Author Report Posted October 2, 2019 Thank you. I’m new to Mooney and still learning it. Battery is on the left side behind baggage compartment. My guess those solenoids were not replaced since 1967. New battery but starter cranks like discharged battery. Might as well replace both of them (starter and master solenoid) before getting to the starter itself. Sent from my iPhone using Tapatalk Quote
carusoam Posted October 2, 2019 Report Posted October 2, 2019 Depends on how you feel about replacing things... some people call that swap-tronics. Sometimes it is as simple as cleaning the connections. High current and 12v don’t really go very well over long periods of time... especially if used in real environments... Some people want to swap out 50 year old devices... Others hold onto things until they are proven to not work... Solenoids used to get OH’d... There is a list of things that can be wrong in the starter chain of events... One of the starter companies has an excellent trouble shooting guide... Are you familiar with the MS search function? Somebody posted a link to the guide around here recently... It won’t make a difference what starter you have... for the trouble shooting that is... By the way, it’s pretty obvious you are new to Mooney... or does newowner mean something else? If your solenoids were replaced... there will be a note in your airframe log that describes where and when it got replaced with what parts, and who did it.... Some people review their logs and take notes... how often some things get replaced... kind of gives an outlook to what is coming next... you really know your plane when you are replacing things a second time and it’s been many years in between.... vac pumps and magnetos are really important on this list... some things are original.... and still working... Some things get OH’d... it may be more economical to just replace.... Best regards, -a- Quote
MB65E Posted October 2, 2019 Report Posted October 2, 2019 I replaced mine with the upgraded amperage relay as the old school one was NLA. Turns out I had a battery issue as well. Now my new 2yo $200 Eaton relay only works when you tap it. Guess whats going back in...the original from 1965! I’d properly charge the battery with a top charge and remove and reinstall all connections after spraying the relay down with contact cleaner. Deoxit Gold is magic. -Matt Quote
Newowner Posted October 2, 2019 Author Report Posted October 2, 2019 Thanks for the info. I ordered both solenoids from Spruce. Will see if I can reuse old ones or just replace them. Sent from my iPhone using Tapatalk Quote
Shiny moose Posted October 2, 2019 Report Posted October 2, 2019 Clean all your connections ! All of them! re tighten them properly. If your master relay is working its working, check of voltage at battery side of starter relay for considerable voltage drop, you stated your power turns on but your your starter is turning slow I would start at the starter, is it old, worn out, drawing high amps, when was it replaced. My .02 1 Quote
N201MKTurbo Posted October 2, 2019 Report Posted October 2, 2019 On my old 67 F I had a similar issue and it turned out to be a bad connection between the avionics shelf and the airframe. The battery is grounded through the shelf. I removed the four bolts, lifted the shelf and cleaned the contact areas with scotch brite and all my problems went away. 2 Quote
Ragsf15e Posted October 3, 2019 Report Posted October 3, 2019 13 hours ago, N201MKTurbo said: On my old 67 F I had a similar issue and it turned out to be a bad connection between the avionics shelf and the airframe. The battery is grounded through the shelf. I removed the four bolts, lifted the shelf and cleaned the contact areas with scotch brite and all my problems went away. This is good advice. Basically, there are lots of connections between the battery and starter (alternator too) and they’re all susceptible to some corrosion causing a bad connection. Swapping in parts is fine, but as a “slightly older owner”, I think you’ll soon find out that the 50+ year old electrical system will have lots of ways to fail and surprise you. I’d highly recommend getting out the voltmeter and testing voltage starting with the battery itself and then moving through the system. Battery should be ~12.5-13.0ish. There should be minimal drop as you move past the master solenoid (with it on obviously). Then check out the voltage at the starter solenoid in the engine compartment. Finally, have a friend help check voltage at the starter. You will find your culprit in minimal time and replace less parts. 1 Quote
N201MKTurbo Posted October 3, 2019 Report Posted October 3, 2019 1 hour ago, Ragsf15e said: This is good advice. Basically, there are lots of connections between the battery and starter (alternator too) and they’re all susceptible to some corrosion causing a bad connection. Swapping in parts is fine, but as a “slightly older owner”, I think you’ll soon find out that the 50+ year old electrical system will have lots of ways to fail and surprise you. I’d highly recommend getting out the voltmeter and testing voltage starting with the battery itself and then moving through the system. Battery should be ~12.5-13.0ish. There should be minimal drop as you move past the master solenoid (with it on obviously). Then check out the voltage at the starter solenoid in the engine compartment. Finally, have a friend help check voltage at the starter. You will find your culprit in minimal time and replace less parts. You are absolutely correct with one caveat. There will only be a voltage drop across a high resistance joint while current is flowing. It is best to do these measurements while you are cranking the starter. You will need someone to crank and one to measure. Be careful out there. Quote
Yetti Posted October 3, 2019 Report Posted October 3, 2019 There are four big power solenoids. two by the battery if you have the aux power inlet there is one for that energized by the third pin. The other one is the Master controlled by the master switch. There is one on the pilots footwell. There is one on the starter. Depending on your tractor starter it could be that also. Check the ground strap on the engine and make sure all connections are shiny bright. It is also possible that wires inside of lugs can develop enough corrosion that there is a bunch of resistance. Quote
Newowner Posted October 3, 2019 Author Report Posted October 3, 2019 Thank you all for great advices. I’ll be working on it tomorrow and clean all contacts, check voltage and make sure battery ground is good to the airframe. Sent from my iPhone using Tapatalk Quote
Guest Posted October 3, 2019 Report Posted October 3, 2019 5 hours ago, Newowner said: Thank you all for great advices. I’ll be working on it tomorrow and clean all contacts, check voltage and make sure battery ground is good to the airframe. Sent from my iPhone using Tapatalk This might be helpful before installing new expensive parts. https://skytec.aero/aircraft-starter-performance-issues/ Clarence Quote
Ragsf15e Posted October 3, 2019 Report Posted October 3, 2019 12 hours ago, Yetti said: There are four big power solenoids. two by the battery if you have the aux power inlet there is one for that energized by the third pin. The other one is the Master controlled by the master switch. There is one on the pilots footwell. There is one on the starter. Depending on your tractor starter it could be that also. Check the ground strap on the engine and make sure all connections are shiny bright. It is also possible that wires inside of lugs can develop enough corrosion that there is a bunch of resistance. Interesting... I have a solenoid in the engine compartment, low on the pilot side near the pilots feet. I assumed it’s the starter solenoid but I haven’t chased the wires. Is this the same one you reference in the pilots footwell? I wonder if different models have them different places? The other one I have is right next to the battery like you said. Quote
Ragsf15e Posted October 3, 2019 Report Posted October 3, 2019 12 hours ago, N201MKTurbo said: You are absolutely correct with one caveat. There will only be a voltage drop across a high resistance joint while current is flowing. It is best to do these measurements while you are cranking the starter. You will need someone to crank and one to measure. Be careful out there. Good point. If you have the master on, there will be power, but even a minimal voltage drop might be a bigger deal when you crank the starter because it will get a lot bigger with more amps. When chasing alternator issues with just the master on, Zeftronics has you look for 0.5 or greater drop from battery or bus, but with the starter, even that might be too much. Probably best to check it like N201MKTurbo said. Carefully... Quote
Yetti Posted October 3, 2019 Report Posted October 3, 2019 3 hours ago, Ragsf15e said: Interesting... I have a solenoid in the engine compartment, low on the pilot side near the pilots feet. I assumed it’s the starter solenoid but I haven’t chased the wires. Is this the same one you reference in the pilots footwell? I wonder if different models have them different places? The other one I have is right next to the battery like you said. The thread is titled "Continuous duty solenoid" So technically there are two. The Com one up high above the Copilot. And the one by the battery controlled by the master switch. The one on the footwell is intermittent duty but high amps for the starter. There is usually another one on the starter. I would never use a metal can solenoid for continuous duty as they have a really high failure rate. Quote
moodychief Posted October 4, 2019 Report Posted October 4, 2019 Have you considered the power cables? If they are the originals there can be unseen corrosion in the cable which impacts the power to the starter. I replaced mine this year with Bogert cables and couldn’t believe the difference in cranking. You need to know where your ground wire attaches and if it is zero or 180 degree fitting. Quote
Ragsf15e Posted October 4, 2019 Report Posted October 4, 2019 20 hours ago, Yetti said: The thread is titled "Continuous duty solenoid" So technically there are two. The Com one up high above the Copilot. And the one by the battery controlled by the master switch. The one on the footwell is intermittent duty but high amps for the starter. There is usually another one on the starter. I would never use a metal can solenoid for continuous duty as they have a really high failure rate. Ok, I’m learning, keep talking... what does the com one above the copilot do? Is it powered by the avionics master? Where above the copilot? Behind instrument panel or roof? Thanks! I’ve looked at the maint manual electrical diagrams and they are pretty hard to follow because they use a lot of symbols to represent parts and I can’t find a key. Probably a standard for electrical, but I’m a little slow on EE. Quote
Yetti Posted October 4, 2019 Report Posted October 4, 2019 The com relay above the duct and the below the windscreen provides power to the com bus bars. The lower two in my F. the relay is a normally closed relay. So power is flowing to the radios buss when the power is off (failsafe mode for radios to work). When you flip the Comm Master it sends power to the relay and it opens. Also in my plane (75F) there is a wire that goes to the starter solenoid. When you energize the starter it will shut the comm buss off to protect the radios it's not EE stuff, just flow diagrams. Quote
Charles22 Posted October 24, 2019 Report Posted October 24, 2019 On 10/4/2019 at 12:34 PM, Yetti said: The com relay above the duct and the below the windscreen provides power to the com bus bars. The lower two in my F. the relay is a normally closed relay. So power is flowing to the radios buss when the power is off (failsafe mode for radios to work). When you flip the Comm Master it sends power to the relay and it opens. Also in my plane (75F) there is a wire that goes to the starter solenoid. When you energize the starter it will shut the comm buss off to protect the radios it's not EE stuff, just flow diagrams. I am having an issue where my battery master switch is somehow grounding, and turning on/not turning off. It’s a 1975 and we replaced the switch, the solenoid now twice, and the small ground wire from solenoid to master and the issue is back.... could it somehow be grounding out through the avionics bus or something along those lines??!!! Quote
Yetti Posted October 24, 2019 Report Posted October 24, 2019 20 minutes ago, Charles22 said: I am having an issue where my battery master switch is somehow grounding, and turning on/not turning off. It’s a 1975 and we replaced the switch, the solenoid now twice, and the small ground wire from solenoid to master and the issue is back.... could it somehow be grounding out through the avionics bus or something along those lines??!!! Its all positive on the Master switch Master Solenoid. So if it is "grounding" out you would have big sparks. So I am going to guess that your master solenoid is staying on and not turning off when the switch is turned off. The master solenoid can weld itself on. There could be a short with another positive wire that energizes the master solenoid. This would most likely could happen at the switch. It is connected to a buss bar with the other switches. It is possible for the panel to sag and the switches hit the cromolly tube that is right below them. Use your cell phone camera to see what is going on behind the panel and the row of switches. Could also be an errant wire back there. A positive wire goes from the master over to the fuse panel that connects to the comm relay. so no. Quote
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