Newowner Posted October 17, 2019 Report Share Posted October 17, 2019 Today my original 1967 M20F fuel valve start leaking after I took sample of fuel. AP looked at it and said they riveted in and not removable. Any ideas or solutions for that? Thanks. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
corn_flake Posted October 17, 2019 Report Share Posted October 17, 2019 My M20E looks like this. It sure look like it's screwed in. Quote Link to comment Share on other sites More sharing options...
Newowner Posted October 17, 2019 Author Report Share Posted October 17, 2019 Mine looked different. They totally even with wing surface and there is no way to remove them. They have four rivets around. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
jamesm Posted October 17, 2019 Report Share Posted October 17, 2019 Mooney has service bulletin M20-188-1 that address this issue. My IA and I did my '67C Model about 20 years ago I believe I got the parts from Lasar. https://cdn2.hubspot.net/hubfs/4147179/technical_documents/service_bulletins/sbm20-188a-1.pdf James Quote Link to comment Share on other sites More sharing options...
Newowner Posted October 17, 2019 Author Report Share Posted October 17, 2019 Yep. Just talked to the shop. They said it’s needs to be drilled out and install new removable drains. 10hrs of labor cost plus parts. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 17, 2019 Report Share Posted October 17, 2019 Funny... my 65C had removable sump drains... The important next step is to find out what is getting stuck in the drain... My challenge was the mild steel (non-stainless, rust supply) fuel neck at the top of the tank was continuously sluffing off little bits of iron oxide... The little rust bits would get stuck in the drain, and show up in the separator screen... So... while you are figuring out the small details... look around for the larger details... Try and exercise the sump drain until the bits come out... it may take a few gallons... use a bucket, be prepared with proper fire safety equipment... a bucket of fuel in dry weather is very dangerous... PP thoughts only not a mechanic... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
Newowner Posted October 17, 2019 Author Report Share Posted October 17, 2019 Thanks Carusoam, I’ll try to drain lot more fuel but my guess I’m due for drain valve replacement. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 17, 2019 Report Share Posted October 17, 2019 Getting the modern(?) replacement is a good idea... One day in the next decade or so, you may encounter the same challenge... Many MSers have a spare drain, spark plug, and tools kept in their Madison Bag... Other variations of this situation include a change of drains that came with fuel bladders... got any bladders with that? Best regards, -a- Quote Link to comment Share on other sites More sharing options...
cliffy Posted October 23, 2019 Report Share Posted October 23, 2019 Make sure you get the correct drains They come with "high" windows and" low" windows. Also many different thread sizes. Pick carefully IIRC you want the LOW windows so gas drains from the real bottom of the tank and not another 1/4 " higher. There are a couple of manufacturers and one builds them so you can remove them and replace the O rings on them instead of having to by another new valve if it starts giving you problems again The other makes them so you CAN NOT replace the o rings. Quote Link to comment Share on other sites More sharing options...
Immelman Posted October 23, 2019 Report Share Posted October 23, 2019 Having the drains that can be removed with a wrench is a big plus. But don't commit to that just yet. I'll bet its a piece of sediment caught in the valve causing it to not completely close. Get yourself a big glove to protect your arm from gas. Get your fuel tester, or a small screwdriver, and actuate the drain over and over and over again. This might do the trick. Quote Link to comment Share on other sites More sharing options...
Newowner Posted October 23, 2019 Author Report Share Posted October 23, 2019 I did try to do that for 30min and also blow compressed air but it’s still dripping. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Immelman Posted October 23, 2019 Report Share Posted October 23, 2019 1 minute ago, Newowner said: I did try to do that for 30min and also blow compressed air but it’s still dripping. Sent from my iPhone using Tapatalk Bummer man, might be time to part ways with some money. Then one other thing to think about: if you do put the new drains in: Have a third (spare). Carry it with you with your spares and tools. On the odd chance you're away from home with a leaking drain, you can swap in the field and not be AOG.... Quote Link to comment Share on other sites More sharing options...
Prior owner Posted October 23, 2019 Report Share Posted October 23, 2019 When I opened up my tanks, the amount of sediment in there was notable. Plenty of crud. Quote Link to comment Share on other sites More sharing options...
Immelman Posted October 23, 2019 Report Share Posted October 23, 2019 Just now, PilotCoyote said: When I opened up my tanks, the amount of sediment in there was notable. Plenty of crud. Same here. I took my time cleaning during the last tank patch project and that stopped most of the sediment.... of the pink sealant nature. Take your time blowing, vacuuming, and wiping if you ever have to open your tanks. Quote Link to comment Share on other sites More sharing options...
Prior owner Posted October 23, 2019 Report Share Posted October 23, 2019 Blow air up through the bottom of the drain to clear it. The fuel sending unit can be removed to visualize what sediment you have in there Quote Link to comment Share on other sites More sharing options...
Newowner Posted October 23, 2019 Author Report Share Posted October 23, 2019 I did blow air up and it got better but still dripping. Going in 2 weeks to replace them and do that SB about drains. Then will also clean inside the tanks. Thanks everybody for your input. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
chriscalandro Posted October 23, 2019 Report Share Posted October 23, 2019 10 hrs seems like a lot. Quote Link to comment Share on other sites More sharing options...
salty Posted October 24, 2019 Report Share Posted October 24, 2019 (edited) Not considering you have to drill out the rivets on the old one, remove the upper access panel, install a patch plate, and reseal around the new valve, plate and access panel. Frankly, I don’t think they can do it in 10 hours. I’ve got all the supplies to do this during my annual. My mechanic has been dragging his feet getting around to helping me out with it..... I’ll know more once we actually get er done. Edited October 24, 2019 by salty 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 24, 2019 Report Share Posted October 24, 2019 Compare notes with this thread currently in motion... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Guest Posted October 24, 2019 Report Share Posted October 24, 2019 14 hours ago, Newowner said: I did blow air up and it got better but still dripping. Going in 2 weeks to replace them and do that SB about drains. Then will also clean inside the tanks. Thanks everybody for your input. Sent from my iPhone using Tapatalk We did this conversion on a E model recently and the kit was back ordered at Mooney. The plate nut is really the difficult part to obtain and is listed in SB M20-188 on the Mooney site, the valve is readily available and the cover patch is just a small piece of aluminum. If you strike out I may still have one in stock. Clarence Quote Link to comment Share on other sites More sharing options...
bob865 Posted October 24, 2019 Report Share Posted October 24, 2019 Had ours done when we resealed the tanks. Right before the reseal we had one that started leaking. The valve got replaced, but the leak persisted. Changed the valve twice in total, but when Edison was doing the reseal he called and said the seats were corroded. Changed them and no leaks since. Pics of the old corroded parts are attached for reference. 2 Quote Link to comment Share on other sites More sharing options...
0TreeLemur Posted October 30, 2019 Report Share Posted October 30, 2019 On 10/24/2019 at 6:45 AM, bob865 said: Had ours done when we resealed the tanks. Right before the reseal we had one that started leaking. The valve got replaced, but the leak persisted. Changed the valve twice in total, but when Edison was doing the reseal he called and said the seats were corroded. Changed them and no leaks since. Pics of the old corroded parts are attached for reference. We had the same problem. Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted October 30, 2019 Report Share Posted October 30, 2019 I’m guessing water in the tank that couldn’t be drained caused the seats to corrode?Tom Quote Link to comment Share on other sites More sharing options...
RobertGary1 Posted November 5, 2019 Report Share Posted November 5, 2019 I think its reasonable to have to change them every 2 generations. Best to change it now vs when you're out of town with the family and it wont' seal up and you dump a tank full of fuel on the ramp. -Robert Quote Link to comment Share on other sites More sharing options...
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