testwest

You are welcome! Glad to help. If you read some of the posts over in the Modern Mooney section, you'll see I'm payin' it forward, several great people over there bent over backwards to help me out with some strobe info. Edit: Here is a picture of the CHT piggy-back probe!

Jose wrote: "I am installing an EDM 700 in my 1968 M20C and I will be replacing the existing CHT bayonet probe in cyl# 3 with the JPI probe but I want to retain CHT information in the factory EGHT gauge." So, the only way to legally do this is to install the JPI piggy-back CHT probe, it is JPI part # 5050A. Just remove your factory probe from the cylinder. The 5050A screws into the cylinder at that same boss, and then your old factory CHT gauge probe screws into the back of the piggy-back adapter, hence the name. The piggy back has wires coming from it (type K) and an engine ground, hook those to the JPI and the engine case, respectively. Your factory CHT will work just like always, all four of your JPI CHTs will be accurate too, and you won't use your poopy language when changing the #3 spark plug. These were about $75 from JPI but I am not seeing them on their web site right now. But, Jose, you are in luck. I have a 5050A that is now surplus to my needs, since we are installing a JPI 930 that has primary certification. I'll sell it to you for $50 plus shipping. Or, if you have not bought your EDM-700 yet, I have a complete EDM-700 with the latest factory refurbishment, fuel flow and the entire complement of BRAND NEW probes. $1000 for everything and I'll throw in the 5050A for free. Don't try to splice your factory CHT probe, don't inop the gauge or try any other substitutions listed above. There really are only two correct ways to do this with a CHT advisory instrument, that is the spark plug probe on #3 while retaining the factory CHT probe, or the piggy-back. Also, by way of education, make sure you know what is meant by primary indications versus advisory indications. I'll leave that as an exercise for the reader....but not knowing this and simultaneously contemplating some of the alterations to the factory CHT outlined above could easily lead to making your airplane unairworthy.

Most definitely a Hoskins strobe there. The two screws and the "bumpy" fairing around the strobe tube base are the giveaway. A Whelen tip assembly looks like the attached picture. Note there is only one screw holding the fairing in place, in the center. Unfortunately, the A490 Whelen power supply that replaces the Hoskins power supply can't be synchronized with another. Not true, Normy! The Whelen A490ATSC power supply has a synchronization capability. See here. http://www.whelen.com/_AVIATION/catalog/Power%20Supplies.pdf These are about $298 from Aircraft Spruce. Watch your power loading, though, these are 4 amps each, you put three of them on the stock 7.5 switch/cb and it will break (as in un-make) the connection. If you have a J earlier than 24-0764, you do not have the synch wire install and would have to fish a wire thru the wings to match the wiring diagram #800330 E2, which applied to s/n 764-900. We don't have a rotating beacon, only the tip strobes...and the tail strobe is being installed.

So, for jetdriven, ya can't give me anything for this, it is my pleasure to share the information!!!! We have a very early M20J, s/n 24-0042 to be exact. We have been upgrading this airplane extensively to reflect later improvements and gain efficiency. One of the upgrades was the retrofit of the streamlined wingtips found on M20s after s/n 764...these have the nav and strobes in the tip, but they do not have the forward recognition light (they are pretty problematic, search this forum and you will find lots of info). They also do not have the trailing position light in the tip, either. These tips duplicate the factory install exactly, that also involves changing the outboard aileron rib, the counterweight and the outboard wing skin. Once this is done, however, the spherical coverage of the wing tip strobes no longer meets the FAA requirement for anti-collision lighting in the aft quadrant, since the strobes are buried in the tips under plexiglass. Therefore, the tail light in the rudder must be upgraded to a tail/strobe. Here is where it gets interesting. Many M20Js have upgraded some components of their strobe lights. The original Hoskins power supplies for the wing tip strobes are also mounted in the wings, near the tip on an inspection plate. I am pretty sure those supplies are not easily or economically repairable. Whelen makes a replacement power supply, but the wires have to be changed in the connector going to the Hoskins flash tube. Approved data here: http://www.whelen.com/install/137/13706.pdf So this is what we have on 201JX. One of the Hoskins power supplies failed back around 1990 or so. Both wing power supplies were changed for Whelen double-flash A490s. I know this because the wingtip light is a Hoskins (the fairing between the nav light and the strobe light has a little bump for the flash tube base, and on a Whelen light the fairing is smooth)...but the strobes go FLASHflash, which indicates a Whelen DF power supply. AFAIK, no Hoskins power supplies have multiple flashing capability. Of course it would have been nice to simply read this in the logbook, but........ We have a good Hoskins power supply...and we have a good Whelen A500 tail position/strobe to replace the Grimes position light on the rudder. I knew later configurations of the J had the Hoskins tail power supply mounted somewhere, this information came from looking at the wiring diagrams. But the actual physical mounting was not well documented on paper, which is why I needed the pictures! BTW, the same 7.5 amp switch/circuit breaker is used for both the two and three power supply configurations. One additional 18 gauge wire goes from the switch to the lower fuselage wiring connector, pin 16 to be exact. Then, an 18 gauge shielded wire (with the shield open at the forward end and grounded back near the supply at the tail) goes to the power supply. If we had 3 Hoskins supplies, I would also hook all three yellow synch wires up and have synched strobes. But, we will have the two wings going FLASHflash, each on his own drummer, and the tail going flash-flash-flash, at some other frequency. It will provide anti collision protection, for sure. No one with a sense of rhythm will want to be anywhere close.

duplicate post, sorry

jetdriven wrote: "Does anyone know how to substitute a Whelen or some other flash tube in the Hoskins wingtip to keep it going?" I do. And so does Whelen, here: http://www.whelen.com/install/137/13706.pdf Assuming a Whelen flash tube will physically fit the nav light assembly on the wing tip, you will need to swap the lines in the Molex connector attached to the flash tube. Hoskins and Whelen strobe power supplies use the exact same 3-pin Molex connector to connect flash tubes to power supplies, but they do not use the same pin out. Hoskins goes anode(red-labeled B+ on the supply) - trigger(white) - ground(black) and Whelen goes anode (red) - ground (black) - trigger (white). So, buy a new Whelen flash tube. Make sure it fits in the wing tip assembly. Then, look at the three-pin Molex connector attached to the Whelen flash tube, and get a Molex pin extraction tool (GC/Waldron, .093" extraction tool p/n W-HT-2038-P, Radio Shack, Fry's or online). Leave the red wire where it is, push out the black and white wires from the connector using the Molex extraction tool, and snap the wires back into the opposite holes, so you have red-white-black. Plug in the flash tube to your Hoskins power supply in the matching Molex receptacle on the black box, and you are done!

So, Jet, you are correct, the yellow wire coming from the Hoskins power supply is a synchronization signal. Unfortunately, the earlier Whelen A490 power supplies can't be synch'ed to a Hoskins....or even each other. There are version of the 490 that have a snych capability, but they are 4 amps each, and your strobe cb switch is 10 amps, so three power supplies may pop the switch.

Dave, got those pictures, you are the BOMB!!!!! I can now duplicate the tail strobe install used for Mooneys from s/n 764 thru 942 or so, the electrical information is on the wiring diagrams in the Service Manual and the pictures will allow a physical duplication of the installation. Thanks! Drinks on me when we meet, I'll be at Edwards AFB in a couple weeks, you are at El Monte, right? BTW, the BFG and Hoskins are identical, looks like Goodrich took over the manufacturing from Hoskins/Symbolic Displays for awhile there.

I know, dude, that is just awesome! I'll pay it forward in info and pictures of our upgrade. I am making the new instrument panel myself, the material is 6061-T6 aluminum of .100" thickness, mounted on 10 mounts like the Lord mounts except allowing for flush screws instead of the acorn nuts, etc etc. Stand By!

Outstanding!!! If you feel like taking off that cover and showing the install details too that would be AWESOME! Right now it looks like we will have Whelen power supplies flashing Hoskins tubes in the wings, and a Hoskins supply running a Whelen strobe in the tail. Definitely not a purebred dog here.

Bumping this, any takers out there???

Thanks a whole lot to Peter and Scott McCray!!!! Not only did they get the shots I needed, Scott sent me a baker's dozen highly detailed shots of the alternate static valve on his airplane. So, the early M20Js mount that valve directly to the back of the instrument panel, and they only have two rocker switches to the left of it, namely the master switch and the avionics master switch/circuit breaker. Later versions have up to four rocker switches in that location, so Mooney got a longer actuating shaft for the valve and mounted it a couple inches forward on longer screws and standoffs to make room for more switches. We are doing an Aspen upgrade on ours, and need to put in an "EFIS Power" rocker sw/cb next to the Avionics Master to run it. Guess what, Mooney has dedicated "EFIS Power" rockers available, 8 amp, just right. The black ones are in stock and the white ones are 5 weeks ARO. Got it thru Dan at LASAR, they are doing great work there, and deserve your business! Less than $200 for a switch that looks like the others, instead of some of the kludge jobs I see on other installs out there. But to get that, we have to go to the later config on the alternate static valve. Now I have all the answers I need to make that happen, just for the nominal cost of a future beer (or 6) for my buds here. Mooneyspace is GRRRRREAT!!!!!

No $25 for you!! But I'll buy a round somewhere just 'cause you made me laugh. Anyone else? $25 is 1/4 of an aviation cheezboyger.........

You'll earn this one, I need pictures of the install of the panel mounted alternate static valve from the back....on an M20J that has the 4 rocker switches left of the pilots control column. Ours only has two switches (the master and the avionics master) and I want to add a third rocker for our Aspen (it will be labeled EFIS POWER and look just like the other switches....a Klixon 20TC2-7.5 to be exact). However, on our airplane the alternate static valve is mounted sideways and the fittings would interfere with any switch bodies aft of the panel other than the two originals. And yet, later M20Js have 4 rockers there and the alt static valve right next to that. All the part numbers are the same and the parts diagram does not show a vertical mount........ So $25 via Paypal for the first usable pictures of that installation, the higher-def the better. No pictures of the late install of the alt static down by the nose gear box, puh leeze!

Hi everyone I need pictures of the installation of a Hoskins single power supply for the tail strobe of a later model M20J....this would be one with the swept wing tips but no trailing edge wing tip white lights. The more detailed and hi-definition the better. I think the supply mounts on or near an aft tail inspection panel. I'll send $25 via Paypal to the first person that can email me enough photos so I can duplicate the install on our 1977 M20J. Please, no shots of a Whelen A413 or HDACF in the avionics/battery bay, or pictures of your strobe on the rudder, thanks!

Gone already!

Thanks dude! Your cut is in the form of a beer when we meet. Or something like that.

It is, I'll check my PMs.

We are going to be selling a used JPI EDM-700-4 engine analyzer with the Fuel Flow Option and a COMPLETE set of brand new EGT, CHT, and Oil Temp Probes and the Fuel Flow transducer (injected engine) next week. This would cost new $1648 plus $600 for the FF plus $185 for the oil temp probe. See here: http://www.jpinstruments.com/Price_List.pdf Best offer over $900, or first guy to offer more than $1K gets it plus free shipping. Game on!

PM sent!

How about don't use a mac cause they're junk... I sure don't know who wrote this......not me!!!!

I think it was 210hp or so. And you are right, it is possible to reduce margins if you pile up a few mods....

Yes, indeed! What you said.

TAS calculation from Byron's sheet #2 KIAS: 141 KIAS (IC): 141 since we don't have an instrument correction card. Byron! Homework for your next pitot-static check! KCAS: 139 (from the Mooney POH Airspeed Calibration Chart) Ind Alt: 4500' Altimeter Setting: 30.23 OAT: 48 de F: From the "MyE6B" app on the iPad: TAS: 148 (you calculated 152) Density Altitude: 4479 feet Pressure Altitude: 4215 feet. If your TAS is verified correct by some other method like a low altitude speed course or GPS speed course, I still think you have an issue with that airspeed indicator, and it is reading about 3 or 4 knots low.

That 15.13 factor is based on compression ratio, and is correct for an 8.7:1 CR engine like we have in the IO-360-A*. Interestingly, if you happened to have the Firewall Forward STC for the IO-360, it would be a 10:1 CR, and that gives a factor of 16.6. So at 9gph LOP in a standard IO-360, you get 135 hp (67.5% power, a very good place to cruise) and in the Firewall Forward STC, that same LOP fuel flow gives you 148 hp (74% power). For this reason, I have always been surprised that STC has not been more popular. It is also the reason I avoided all of the low compression ratio options on the Aerostar...they are terrible as far as efficiency goes.