Mooney-Shiner

Its crazy how close these fuels senders in specs and appearance to antique 1930-s Chevy fuel senders. https://www.classicchevy.com/chevy-gas-tank-sending-unit-all-except-station-wagon-and-sedan-delivery-1949-1952-80-244983-1.html?utm_source=google&utm_medium=cpc&adpos=&scid=scplp80-244983-1&sc_intid=80-244983-1&gclid=CjwKCAjw9-KTBhBcEiwAr19ig1bTNW9sEpOVEct-GLBF84VQq0gaiCZKqEpG_08M8UlqWQA083-FjBoCY7cQAvD_BwE&gclsrc=aw.ds

Yes, there are two point at each wing root. The pick up is all the way aft and bottom. Move the seat forward, remove the trim and push the wall carpet to the front

Yes, sure. From Maxwell source: 1. The first rule to remember in chasing a fuel leak is: The source of the leak is never where the leak appears on the out side of the tank. 2. Remove the fuel from the tank. 3. Turn the fuel selector off. 4. Remove the top fuel tank access panels on the wing that has the leak. The panels are removed by first removing the screws. 5. Once the screws are removed, we use masking tape to tape around the access panel and the middle of the panel for protection of the paint. The panel is sealed with a sealant. Do not beat on the panels. An elephant could stand on the panel and it would not come loose. 6. Next, we use a thin putty knife, that has been sharpened on one side, to slide in between the seam of the access panel and the wing. Using a nonmetallic hammer, gently work the putty knife between the skin and panel. It may take several times around the panel with the blade and hammer, each round a little deeper under the skin, until the panel releases. 7. Once the panels are removed we place mirrors in the bottom of the tank so that we will be able to see the upper seams of the tank. Do not cover the stringers in the bottom of the tank. Many leaks are in this area. 8. Next we apply liquid hand soap, thicker the better, to all the seams in the tank. 9. We now cover all the removed access holes in the wing with Plexiglas. Fig. 3. The Plexiglas covers the entire hole including screw holes. The Plexiglas is held in place by masking or duct tape around the out side border forming a seal. The Plexiglas can be cut from an old windshield or purchased at most hardware stores. New glass is preferred as you will be looking thru the glass to find our leak source. 10. Next we take a standard shop vacuum cleaner. We attach the hose from the vacuum cleaner to the vent on the fuel tank. And no, this will not collapse your tank. 11. Turn on the vacuum and, using a flashlight, look thru the Plexiglas panel and look for bubbles in the soap. The mirrors should be positioned so that you can see the entire interior of the tank. 12. Bubbles indicate the source of the leak as air is drawn into the tank thru the leak. 13. Once the leak, or leaks, are found, Fig .5, the area will need to be thoroughly rinsed with water, dried, cleaned and repairs made using procedures in the Mooney Service Manual.. 14. Two types of sealant are recommended in the manual. PRC and Flame Master brands. We use Flame Master CS3204B-2 for repairs in the tank and topped with CS-3600 for a protective coating and CS3330B-2 for access panel sealant. Fig 6. We use sealants in Semkits that contain both sealant & activators. They are mixed together in a small caulking tube. Once mixed together, we transfer the sealant to a cup and apply with small acid brushes. The sealant will apply easily if thinned with a small amount of MEK. 15. Replace the access panels using CS3330B-2. I recommend at least 48 hours before fuel is added to allow for proper curing of the sealant. Temperature is key to a successful repair. Avoid cold weather & high humidity if possible. Most leaks are easily found and repaired using this method. I share this procedure with you so that you and your mechanic can locate and repair your Mooney’s fuel leak. We welcome you to visit our service center at any time. I would also add that for the horizontal surface leaks, I would use Class A compound (3204) as the Class B is too think to spread out and fill all the cavities. http://flamemaster.com/cs-3204-class-a-b-c Can't find my old thread, here is what this diagnostic look like. I used my GoPro inserted into the wing to show the leaks. Feel free to ask any questions. @carusoam Quite honestly, by now I think we should build some sort of the primer for Tank Patching because it is such a common issue with the Mooney. From what I gather, the reason why Mooney suck/blow so much is because of original assembly method of the integral wing tanks. Unlike other aircraft, Mooney first assembled the tanks, then applied the sealant (other aircraft applied the sealant as they assembled the tanks). So anytime you flex the wings beyond some level (hard landing, etc), this creates a break in the sealing layer.

I would check to make that it is a pick up that is leaking. If it is, then it is unlikely that the rivets themselves are leaking. On the inside of the tank the riveted area is covered with Pro-Seal sealant. It is likely that that sealant had failed. I would open the inboard tank access, apply the soapy solution and pull the vacuum through the vent while observing the possible bubbles though the plexy window.

I finally got to troubleshoot my vac switch(made by Weston, but looks like Sigma-Tec). I untied it from the vac system (still connected to wires) and pulled the vacuum on it with my mouth. The Master switch was on, but the engine was off. The Hi light came up as I was pulling a vacuum. I tried to lightly blow into the switch to cause a “Low” warning light reading, but no light reaction. I know the both of my light bulbs work, because they did light up when I pressed on them. I wonder if the is a way of disassemble the switch to check for the right contacts.

Hello, Bobby, sorry for the delay. I was pretty busy last couple of weeks because I have family in East Ukraine. I got my DG back from Naylor (Gainesville, FL) and finally installed it today. The overhauled DG is performing perfectly. No error at all after 5 minutes. According to overhaul notes, the unit was out of balance and caused the error of 2 degrees every minute (see above). Total price for overhaul was $425 plus replacement of backplate $45 plus UPS freight $30 plus tax. Just a note of caution: be careful torquing the plumbing fittings on the back plate of DG or AI, overtorquing will crack the backplate.

Any Scott's OAT thermometer probes?

Yeah, I will echo a positive opinion on Aeromotors. They did a great work 8 months ago on overhauling my Dukes for about $450-ish. Also great customer service. From talking with them, they told me that they are now rebuilding with more sturdier materials that makes Dukes last as long as Weldon. Also they consulted me on the re-install procedures of Dukes and answered all of my rookie questions. My A&P was happy

You are exactly right!

Thank you, Clarence. I just need to find the torque values for accessory case bolts, as it doesn,t seem that the overhaul manual has the info on accessory items..

Moose, great eye! You are right, the bottom of filter does have isolated leak, but I couldn't believe that the oil filter would leak. Never had leaks on any of my oil filters, car or plane. I guess I'm switching from Champ to Tempest filters now.

Thank you, Clarence. You are right, looks like M20-120 is affecting only J Models. But, confusing enough, Lyc SI 1438a affecting "All four and six cylinder, dual magneto engines with rear mounted propeller governor drives." https://www.lycoming.com/content/service-instruction-no-1438a What a head scratcher...

I will check for fretting. From brief cursory google, it seems that "smoking gun" of fretting is a difficulty to turn the prop immediately after the shutdown of the engine due to binding. I don't think that I have that problem, but I will double check it tomorrow.

Thank you, FC. I went ahead and looked around the oil filter adapter housing with my articulating borescope and it seemed to be dry to me. Video posted: I will keep looking. I also asked Savvy Aviation Q/A and they offered that my Hartzel H-1 prop governor leaks because it doesn't have two P/N 72053 gaskets sandwiching the LW-12347 propeller governor pad plate as per Lycoming Service Instruction No. 1438A. I think this mod was already mentioned couple of times here on the board. Separately, I re-torqued the top 1/4" bolts to Lyc overhaul spec and applied high torque RTV on the leak on the top mating seam of two case halves. It held up pretty good during the ground runups. However, when I went to do some pattern work, I noticed that the oil was once again pushing through the RTV. So now my plan is to clean up this area really well from all the oil/RTV/impurities. Then reapply the RTV or ProSeal, while putting a ShopVac in the dipstick tube to create the negative pressure inside the crankcase to pull the RTV further in the opening between two halves.

Update: I cleaned the engine, did a run up and checked the engine with borescope. One particular area stood out. I uploaded some of the short videos on the youtube: https://youtu.be/JhoQeoxQZ-A https://youtu.be/a-M1RDtYfSw https://youtu.be/JgS2SW9HNOw It looks like the gasket of prop governor(between the governor and crankcase) is leaking. I think it lightly misting the magneto above and drains below on the sump/crankcase horizontal seam and on the suction screen cap. I'm not sure what I can do there. The other area that I noticed to be oily is the bottom case halves bolts, forward of sump and between the starter and alternator. Not an easy place to reach at, but I will try to get in there and re-torque the 1/4 inch nuts at the crankcase bottom parting face to 98-108 inch pounds as per overhaul manual.

Update: We pulled the Directional gyro and sent it to Naylor Avionics shop in Gainesville, FL. Also will have him check out my old Weston electrical switch for Lo/Hi Vac lights, which I suspect is not working. To continue flying VFR, connected the DG’s exhaust and intake together to prevent the vacuum leak and keep my AI running. We went flying today and, for whatever reason, my attitude indicator that previously worked fine decided to sag like it was not getting a vacuum… can’t win here… I need to install a vacuum gauge in the panel, but thats a separate topic. We decided to re-engineer this temporary arrangement. We individually plugged the inflow and outflow hoses and now the attitude indicator works perfect… Mystery... More to follow once we will fly to pick up the re-built DG in Gainesville.

Yes, Sir. I have the same logic as yours. The structural items first (engine, frame, min VFR eqpt requirements), then advanced avionics

Good point on throwing good money after bad... The reason for my "wait and see" approach is that because I'm only 40 hrs into my ownership of my 67F and I'm not sure whether I will have any major capital setbacks with this old plane in the near future. If "suddenly" I will facing major expenses, I will consider cutting my losses and getting out of the plane ownership and settle for renting/partnership until better time in the future. This is why I wanted to wait before throwing major money for Aspen or at least Uavionix AV-30. Although replacing the DG with AV-30 is tempting right now. Considering the cost of overhaul, I'm considering just buying used DG with 90 days warranty for $200-300 and calling it a repair. I'm fine with taking a risk of failure after 90 days.

You are right. My old Rapco pump had a window by the shear shaft. When the pump failed, the shear shaft pieces flew through this window. When I initially saw the crumps on top of my right magnetto, I thought that I had rodents living under my cowling hahaha. Now I know...

Just to follow up. My A&P replaced the Tempest vacuum pump and the attitude indicator is now fully functional, but the directional gyro has slight drift of 10 degrees over five minutes. We replaced the can and valve regulator filters. I connected a vacuum gauge to the inlet of DG and was steadily getting 4 inches of HG or more in vacuum. What else should I check to stop this drift? Below is a time-lapse video over the course of 5 minutes.

Yep! The small Sky Catcher has crosswind component of 13 knots in its POH

Not to hijack the thread, but is there a defined crosswind component max for Mooney? My 67F Mooney came with a rather skinny booklet of POH, which doesn't mention the max crosswind component. My CFI keeps asking me about it, and I keep feeling silly since I don't have a good reference.

That’s unfortunate…I didn’t follow this thread closely, so not sure if anyone mentioned EBay. Even the “as is” items are covered by 30 days satisfaction policy Sent from my iPhone using Tapatalk

Exactly, there is no Lycoming SB on crankcase pressure. So I used the Continental SB as referenced above. Also there was a guidance on using old airspeed indicator. But since I don't have old airspeed indicator laying around, I used the manometer and measured it in inches of water as per Continental SB. I did check my breather line and it seemed unobstructed. I didn't block the breather line during the test, because I wanted to measure the normal operation pressure in the normal configuration. Thank you for the feedback, guys.

Thank you, Coyote. In your experience, how did the JB weld damage the aluminum case? I'm not questioning your comment, but just trying to wrap my head around the problem at hand.