MisfitSELF

Just an update on my particular issue: I found and replaced the 15K Ohm resistors leading from the ignition switch to the RPM gauge. Turns out they were right next to the ignition switch as described in the MX manual. The result: little to no change. Maybe a bit less jumpy in both but it didn't fix the problem. Remember, in my case, it's jumpy in "BOTH" but rock steady in "LEFT" or "RIGHT" and I have the 'electronic' not mechanical RPM gauge. Could the ignition switch but the culprit? It's a Bendix "push to start" style and unfortunately a replacement off aircraftspruce is $600!

It's a 1984 (built in 1983). S/N 1425 I believe. I have a pic somewhere, just not with me at the moment.

My RPM gauge is "jumpy" too. But only in "both". Once I select either R or L mag, it becomes rock steady. My MX manual says it could be one of the 15K OHM resisters going from the ignition switch to the RPM gauge could be bad. I've look under the "hood" but couldn't find said resistors but was able to trace the whole length of the wire. I'm curious if anybody knows where those resistors are typically located. It could be as simple as just getting new 15K ohm resistors since mine are likely 35 years old. Yes, I now realize that I'm replying to a 6 year old thread.... Bruce

I’ve kept on digging and what I’ve managed to find is that my A3B6 may be properly configured with the jumper removed. The Champion/Slick site isn’t really clear but my right Mag (different model number than my left mag) may not have the impulse coupler.

Clarence, Again, that makes sense but where is this documented? The service instruction says to remove the grounding link, but doesn't say if and when you should leave it or reinstall it. I'm looking for an official service bulletin or instruction. Bruce

I happen to have a A3B6 like the OP and it would appear my ignition switch is modified per M20-59A. What you are saying makes sense but can you tell me where it is "officially" documented that M20-59A needs to be reversed if you have the dual mag? Unfortunately all the service instruction says it's "to improve starting characteristics" but it doesn't say why so I can't say for sure that if you have one mag configuration you should have apply M20-59A and if you have another you shouldn't. Please don't get me wrong, I'm not questioning your knowledge. I just want the bulletin or instruction I can show my A&P as to why the reversal needs to be done.

I have a M20J S/N 24-1425 with the Avionics Products landing gear actuator. I just finished my last annual and noted that the emergency extension cable coating or plastic cover is stripping off about 20 inches down (almost at the full travel point). Is there a source for a replacement extension cable? Edit: according to my parts manual it's part number 560254 and theirs a note that it's a "CABLE, EMERGENCY EXTENSION (SUPPLIED W/ ACTUATOR ASSY BY AVIONICS PRODUCTS)" Thanks. Bruce

Jerry, My antennas are definitely not the "wire" kind. I've got two big "shark fins" on the top of my tail. I have a ten pack of BNC splicers on order from Amazon to help trouble shoot. My plan is to connect one to splice the ANT to the VOR1 then taxi or fly around an note if anything improves. Why did I get ten? It was the smallest set I could find quickly on Amazon and it cost all of $6.99 and they are delivered to my door by Tuesday! I would have spent more in fuel to drive to Best Buy or where-ever and then spent like $5 to get one! Bruce

That's precisely right Andy. The Ant gets split to VOR 1, 2 and Glideslope. If the rest of you are curious it's a Comant CI-505 as mentioned in the subject line. I like the idea of getting a male to male adapter and trying one VOR at a time. Bruce

Done that already.

Airplane: 1984 M20J with dual VORs (the original set from 1984!). For a number of months, my VOR reception has been a spotty. By spotty, I mean at mid ranges (20-40ish) miles, the needles would twitch, sometimes lose lock and display the "nav" flags. VOR1 was always a bit worse than VOR2. As I get closer to the stations, it clears up. As I listen to the stations, they morse code is very hard to hear. Obviously (or maybe not so obviously), I have some sort of signal loss thing going on. Where I could, I have unhooked the BNC connections at various points and reconnected them. But I have gotten no improvement. So I suspect I have (in no particular order): 1. Bad antennas (but I have two on the tail so probably not likely) 2. A Bad combiner at the base of the tail (this is "could" be) 3. Bad cable from the tail to the triplexer 4. Bad triplexer 5. Bad radios or cables from the triplexer (again I have two and both behave this way) The cable from the tail forward would be a huge pain to replace, so right now I'm focused on the triplexer or the combiner as the likely causes. Except how often do these fail? They are ~35 years old, so ok they just might. The other reason I'm focused on #2 and #4, is that they seem to be the easiest just to replace. But the triplexer costs ~$230, so before I just start throwing money at this I want to see if anybody else has had similar issues and if they determined their cause(s). Thanks, Bruce

I tried to search this site for discussions concerning Massive Electrode vs Fine Wire. I remember seeing something on this a year or so ago but I was unable to find it. Can someone help me out with a link? (or perhaps we start a whole new thread here rehashing old ground?) My specifics. I own a 1984 M20J with the IO-360-A3B6. I'm currently running massive electrode with Slick mags and will have my next annual in 3 months or so. I remember last annual, when I had the plugs out that the electrodes were looking a bit "footballish" So I may be replacing the plugs this year and am considering going with fine wire and wanted to find out what the Mooney hive minds thinks about one type vs another... Bruce

I got a .pdf replacement from Mooney of the entire and most current M20J parts manual. They were kind enough to e-mail it to me!

I'm missing a page for my 1984 M20J parts manual. Is there a good source to get replacement or .pdf of missing pages? Thanks, Bruce

Thanks again guys for your inputs. I Finally got my Mooney up and running again yesterday. What a pain for "just a vacuum pump failure" Let me give you guys a recap. That oil seal turn out to be a royal b**ch to remove. I tried the allen wrench. I used just a bit smaller than a 1/4" (more like a 3/16") and used my metal cutter to make the short end a little shorter. I started out by tapping and rotating it around so that my force was relatively even. It didn't budge. Then I repeated, harder and harder. Still it didn't budge. I ripped up the old rubber seal portion and heavily dented the seal all around the rim. Still it didn't budge. The allen wrench really did feel like it was almost the right tool for the job as it fit just right but it just wasn't working. I was at the point where I was causing minor damage to the adapter block with the force I was using. Then I tried freezing it. Still didn't budge. Then I tried heating the whole thing to 350 degs. Still didn't budge. I had order the cover so that I could just "cap" it off and hope the KI300 comes out soon and was thinking about ordering a replacement adapter (yet another $350 for a stupid vacuum pump). My A&P came by to check on my lack of progress and he volunteered to take the part home and give it a go. We talked about cutting it out or drilling it out but I didn't have the right tools and drilling seemed risky. He worked to all hours of the night and concluded he needed to some how cut the seal out (which is made out of some serious steal!). It's nearly impossible to get at the seal to cut it with dikes. Eventually, he put it in his drill press with a grinder wheel that fit inside and carefully ground down the seal on one side until he could peal it out. He installed the new seal using a socket to tap it in as suggested above. Before doing that he measured the diameter of the seal and the accessory adapter. Turns out the seal is like 0.001 larger than the diameter of where it goes in the adapter! In addition he was nice enough to "clean up" the minor dings I made in the part. The next day every thing is back together and I have vacuum! Not to scour the Mooney space forums for that pesky engine lobing issue...