ryoder Posted May 9, 2015 Report Posted May 9, 2015 I just had an overhauled directional gyro installed Friday. I flew for thirty minutes on Friday and it was working great. Today a friend and I flew for around an hour before we lost suction. We headed back and I called my mechanic who will look at it Monday. I hope it was a loose hose fitting or something like that. I didn't open the cowl to check myself though. Any danger in a loose hose, kinked hose or something installation related causing me to have to replace the gyro yet again in the future? The worst situation would be a kinked hose or something happening during the installation that killed the pump and contaminated the gyros. Quote
Shadrach Posted May 9, 2015 Report Posted May 9, 2015 I think it unlikely that a fitting cam loose as most are friction fit. If you suffered a complete loss of suction, then I am guessing that your vacuum pump went TU. This is a relatively inexpensive item ($200 or so + core), but it is a PITA to change (maybe 2.5hrs for a good Mooney guy that knows how to do it, more for someone else to learn. I just did mine about 2 weeks ago. The right mag has to come out on the angle valve engine; I'm not sure about the parallel valve in your plane. If your IA will allow it, I strongly suggest you get involved in the process as it will be educational. Quote
ryoder Posted May 10, 2015 Author Report Posted May 10, 2015 He had to pull the filter off during the install and move some things around. The new gyro was longer than the old one and clearance was a challenge. I helped a little with the install. Quote
Bob Posted May 10, 2015 Report Posted May 10, 2015 Look under the cowl and check the hose between the filter and directional gyro. Good chances it has collapsed. Quote
Guest Posted May 10, 2015 Report Posted May 10, 2015 Time for some practice changing vacuum pumps on a Lycoming. If you're pulling mags and oil filters you're wasting time. The Tempest wrench is helpful put not required if have a bit of imagination. Clarence Quote
cliffy Posted May 10, 2015 Report Posted May 10, 2015 How many hours on your vac pump? First guess is a hose installed with the gauge, next is the pump. The Tempest wrench is great for this job. No need to remove anything but the pump itself. My pump has 960 hrs I'm expecting a vac light any time now. May just change it anyway. Quote
Shadrach Posted May 10, 2015 Report Posted May 10, 2015 Im trying to think if it was the nut in the 7:30 or 10:30 position that was difficult to acces. We tried and then just decided to lock the mag and remove. Not a big deal, but I'd have certainly preferred not to. Quote
Andy95W Posted May 10, 2015 Report Posted May 10, 2015 Mac angle headed wrench for the hard to get to nut. Funny thing is, a Snap On angle headed wrench won't work, nor a Craftsman. Only the Mac. I'll probably buy the Tempest wrench anyway. Quote
Shadrach Posted May 10, 2015 Report Posted May 10, 2015 Mac angle headed wrench for the hard to get to nut. Funny thing is, a Snap On angle headed wrench won't work, nor a Craftsman. Only the Mac. I'll probably buy the Tempest wrench anyway. I took a grinder to one of my old craftsman wrenches. It works better than any of the others, but did not change me having to remove a mag. Quote
ryoder Posted May 10, 2015 Author Report Posted May 10, 2015 I don't know how many hours are on the pump. I'll have to look that up. I have to work and my IA will fix it while I'm at work. I bet a hose kinked up too. If that is something that can happen. Will that burn out a pump? Quote
Shadrach Posted May 10, 2015 Report Posted May 10, 2015 The below link is to a Light Plane Maintenance article on dry vac pumps. It's a good read. http://flash.aopa.org/asf/mechanics/downloads/dry_vacuum_pumps.pdf Quote
mike_elliott Posted May 10, 2015 Report Posted May 10, 2015 Time for some practice changing vacuum pumps on a Lycoming. If you're pulling mags and oil filters you're wasting time. The Tempest wrench is helpful put not required if have a bit of imagination. Clarence I have also found to reinstall, a little super glue on your finger and nut will help start the bitch bolt. 2 Quote
Guest Posted May 10, 2015 Report Posted May 10, 2015 I have also found to reinstall, a little super glue on your finger and nut will help start the bitch bolt. Mike, That certainly works well, super glue has more tensile strength than shear strength. I'm a little reluctant to use it after one of my guys glued his eye lids together, then the new one piece eyelid to his eyeball! Nothing that a trip to the emergency department couldn't solve. Clarence Quote
ryoder Posted May 12, 2015 Author Report Posted May 12, 2015 Mechanic called. It's the pump. He ordered one from Spruce for under 200. Should probably be fixed Thursday. Quote
Marauder Posted May 12, 2015 Report Posted May 12, 2015 Mechanic called. It's the pump. He ordered one from Spruce for under 200. Should probably be fixed Thursday. Well that sucks... Ah, I mean, ah, it sucks that it will cost around $400 for the repair The pump obviously doesn't suck, at least not anymore Sent from my iPad using Tapatalk Quote
FloridaMan Posted May 18, 2015 Report Posted May 18, 2015 Yup. Three of the nuts are easy to get to. The last one requires either home made tools, lots of creativity or one of these: 1 Quote
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