Aerodon

JPI have all the manuals online on their website. Installation, operating, FAQ etc.

You should be tracking the hours on all your accessories - turbo, alternator, starter, magneto, vacuum pump etc. Then when you start having problems with anything, the first thing you look at at the years and hours since last replacement. Then the decision process to replace is much easier. I've never had to have the vacuum adjusted. It might be required if you change the number of air instruments you have, or if you change from a 211 to 215 pump, I believe they have different capacities. Airplanes talk to you, if you have over 500 hours on the vacuum pump and are not getting your usual 5" - I would listen. Aerodon

Swaid & Troy, I have a 252 and it has outer, middle and inner gear doors. The inner doors attach to the wing near the fuselage. The middle are what you are calling the inner gear doors and are fixed to the gear leg. I did the Encore upgrade and that required replacing the middle doors and reworking the inner gear doors. S0 I have a set of 'middle' gear doors for you, see below. Don

Try it, you will be surprised by how a good 'first step' makes it easier for unstable people to plant their second step in the right place. I use something similar in the hangar to make it quicker and easier to get in and out of the plane multiple times rather than the airplane step.

I think you are getting it now. Both mags have an impulse couple, when in the 'start position' both should still be working. You should be a little sceptical about freshly overhauled mags, maybe not so much after 100 hours, maybe again after 5 years. Harness condition? Be sceptical of Champion spark plugs, do the resistance check under pressure. Finally, part of the SB to remove the primer diverter valve is to make sure you have the correct 'new style' primer nozzles (see picture). The new ones are taller and create a little dam of fuel. Allowing some time to evaporate may help. And remember you are now priming 6 cylinders at once, you need to find a new 'happy place' for priming duration, waiting, temperature and cranking duration. Aerodon

I checked both my Seneca and C172 handbooks - both require trailing edge heavy. Some surfaces from 0 to 'training edge heavy'. Piper and Cessna use different signs for under and over balanced, but the instructions are clear enough. Seneca ailerons have a wide range from leading edge heavy to trailing edge heavy. Aerodon

Here is a picture of a spare set of M20K weights, about 3.425 lbs each, with threaded metal inserts for mounting. And I'd like to re-iterate what was mentioned above, balancing does not mean the elevator is balanced on the hinge line. Aircraft control surface balancing is the process of ensuring that the control surface 'imbalance' is between the fore and aft limits.

Yes, the Encore weights are considerably bigger and about 1lb heavier, thats why I have a set of original 252 weights. They are solid lead, first step is to see if the 3 mounting holes fit. Then check if the elevators balance within the correct range. If anyone is searching for replacement weights, send me an email - supercub180@gmail.com Don

I have some M20K balance weights that might fit, Ill go look for them. Aerodon

Power distribution from KFC200 manual

The altitude hold/capture requires a 'grey code' input and a baro correction input to work. These are provided by the KEA130 altimeter, but these are hard to maintain properly. I'm installing a G500 / GAD43A etc. and removing the altimeter. But I will need to install a blind encoder for the great code altitude input and the GAD43e will provide the baro correction. Aerodon

I looked at my Mooney wiring diagrams - nothing on the trim power (as expected because it is often part of the autopilot). Then I looked at a KFC diagram, it has a 'FCS' bus (flight control system) that feeds the autopilot, trim and compass system, each with its own circuit breaker. The FCS bus is powered via the main bus, with a relay and a 1A CB. In this way, the entire A/P can be disconnected by pulling the 1A breaker, or the trim can be disabled by pulling the Trim breaker. It's really important that you understand your system, and not mess with the design. The answer you are looking for lies in the wiring diagrams for the autopilot installed in your plane. Don't let anyone make changes without this information in hand. Aerodon

One of my planes is a C172N with a 180hp. On long flights I usually use WOT and 2500rpm, then lean until just before it gets rough, around 10GPH. Recently we did a top overhaul with 4 overhauled cylinders. Now following the same leaning procedure, the engine runs smoothly at 9GPH with no noticeable difference in speed. The old cylinders were mix of 2 original and 2 overhauled cylinders, the problematic ones were the overhauled ones with valve issues. I think the previous owner 'cheated out' and put some crappy cylinders on. I am a big fan on GAMi's on my 6 cylinder Continental turbocharged engines. The principle isn't as repeatable with a 4 cylinder IO360 without a test flight or two. If I had a 4 cylinder IO360, I would take it to my usual altitude and power setting and do the GAMI test, then have a discussion with GAMI on the expected results. Nothing like balanced mixture to make an engine run smoothly and economically. Aerodon

Not all the features on a JPI replace an OEM display. For example - amps. I am probably going to keep my OEM ammeter gauges on my 252, but I have not finished researching. And not all measurements are even required. C172's don't have CHT standard, but the EDM900 now has a CHT that is certified for primary. And then sometimes the FF is written up as a fuel pressure instrument with limitations. JPI will add fuel pressure with redlines, and suddenly you have a new parameter to look at. I think an installer needs to have the airplane POH, type certificate and the JPI STC in hand and do a careful side by side comparison to make sure nothing is lost. And when it comes to piggy backing the FF on the OEM fuel flow, the JPI is isolated with diodes and does not power the transducer. If you had two oil pressure gauges in one oil pressure line, why can you not have two electric counters on the same OEM transducer? I looked at my 252 POH, and fuel flow is not required equipment. MP, RPM, Amps, yes. Then look at the JPI documentation: FF is primary. OAT and Amps are not. How many glass cockpits out there that use the JPI OAT and amps, without the OEM equipment? Aerodon

I've explored all these ideas. Just overhaul your 10 year prop and move on. First overhaul is unlikely to have any surprises, unless there has been blade damage. I'm just having a second 10 year overhaul being done on a 3 bladed prop for my Seneca. All turned out well, but I have to admit to being nervous. I'm not a fan of MT props. I've just heard of too many maintenance related issues and less than helpful service centres. Like particular blade models no longer being made and you have to buy a new version. And buying a full set of blades when one is damaged. And issues with props just out of warranty. And 7 year overhauls instead of 10 years, along with ridiculous costs of shipping 3 bladed props. etc. Yes there is a performance and weight advantage, but that comes at a really high price. Aerodon

You can probably piggy back them, and get both. Only one device powers the transducer, but both read the same signal (signal and ground). Sometimes sides are required on the JPI, send me an email and I'll shoot you a drawing. Aerodon supercub180@gmail.com

You are overthinking this. The transducers over the years come with a variety of threads, 1/8 NPT, 1/4NPT, AN etc. JPI ships with adaptors to fit AN fittings (last time I ordered). You probably have some existing hoses for MP, Oil P etc. with AN fittings, and ideally you can try get JPI to ship an adaptor to match, but will probably fail. Order the kit from me, start your installation, and I'll steer you in the right direction to get the required hoses, adaptors etc. Once you start the installation, you will understand what I am talking about. Aerodon

and tell your insurance company about it, they are better at dealing with third parties than you are. Don

No, just add the transducers and you have an 830. I have transducers and harnesses in stock, send me an email, don supercub180@gmail.com

ill take them, don

Yes, the vacuum pipe from the rear standby vacuum pump is perfect for threading all the wires through from the back. If you installed an engine monitor, they may have used the hole through the firewall for that. That would be a real pain to redo those wires. I would reinstall the engine vacuum pump, the hose through the firewall (even if it means a new hole), the regulator, the gauge etc. Note that vacuum is needed to extend the brakes, a spring retracts them. But I still would not use an electric standby. And I would not give up the vacuum brakes unless really necessary. Aerodon

I agree, thats why I pick my subcontractors more on ability to do the work properly than the price.

So I had an excavator operator hit a gas line 5 minutes after I told him exactly where it was. There was a sorry, but nothing more than that. Cost me $3k, and I was the client not the contractor. Think of how many flat screen TV's that is. Aerodon

OK, I have yet to get a clear answer on this. In a 'normal' system, there is flow through the instruments to the vacuum pump, and the vacuum is regulated by letting in more air through the regulator. If you block off the instruments, then all the flow goes though a regulator. Can it cope? Or should one install a 'bleed valve' with a filter to simulate the instrument flow? These bleed valves are commonly used on venturis to set the vacuum and not expensive. Inline filters keep the air clean so you don't mess up the vacuum pump. And yes, not too difficult to reinstall the vacuum parts for the speedbrakes, and I plan on keeping mine working as long as possible rather than replace. Vacuum pump, manifold, regulator. Aerodon

No I haven't finished the install. Yes I have manuals for you - send me an email supercub180@gmail.com No the G500 has no grey code output, at best the Garmin equipment has a serial altitude (no use) and a baro correction. My plan is to keep a blind encoder for the KFC150, and use the GI-275 or GAD43e for the baro correction. I will have 3 'altitude sources' in the plane - ADC74 airdata (master), GI-275 and the blind encoder. My KAS297 already does not capture the correct altitude, took me a while to work out that it does work, but captures 300 feet high. And there is a blind encoder, I suspect that was installed to make the GPS and transponder accurate, and there is an error in the KEA130. Aerodon