I bought a 1962 182E with Monarch fiberglass main tanks that hold 62 gallons, 60 usable and auxiliary tanks at 18 and 17 gallons. You begin flying the plane on the mains and burn fuel down. When there is room in the main tanks, you press two buttons on a panel mounted control unit which activates transfer pumps. Fuel is transferred from the aux tanks to the mains. One side was inoperative when I bought the plane. The previous owner stated that the problem came on slowly. He would push the transfer button and the green transfer light would come on, but it began to stay on less and less. Finally it would not light at all. I called Monarch (Hartwig) and they said it was unsupported with no known service organizations. I asked if they had a schematic or other information and they sent me a schematic. A pilot friend and I reverse engineered the schematic. They protect from over current draw by the pump. They shut the pumps off when the sense no transfer flow (by a pressure transducer) as the auxiliary tank has gone empty. They also shut the pumps off if they sense the mains are nearing full, (they sense the fuel float voltages at the fuel gauges). Two control boards are housed in an aluminum enclosure, which has a connector to the pumps and a connector to the panel unit. Light sensors are in the control unit which brighten and dim the panel control lighting. It is mostly integrated circuit NOR and NAND gate logic chips with three OP amps using R-C charging to do time delay to account for fuel slosh. You don't want the pumps to shut down for a momentary loss of fuel transfer flow or a momentary rise in main fuel tank level. It must maintain the adverse condition over a time period determined by the charging of the RC capacitors before the control shuts the pumps off for the auxiliaries being empty or the mains being full. There are some yellow warning lights also. I have to look back at the schematic, i dont recall what condition activates the warning lights.

Pretty cool i thought.

Bob

So did you figure out what the issue was?

Having owned and operated a couple planes with Flint tip tanks, I'd MUCH rather use that very simple and minimalist system. Too many potential failure points means there may come a time where you really NEED that extra fuel, and can't get to it.

One of the most tragic aircraft accidents is one where an airplane crashes due to fuel exhaustion, with a bunch of gas still aboard.

I'd figure out a way to simplify that system.....

MTV

I’ve been involved with a few of these installations and I recall the pumps were only required when plumbing the aux tanks to factory mains (bladders). We installed a pair of Monarch fiberglass “slant” mains in a ‘56 180 and the Monarch Aux gravity fed to the Monarch mains. So I don’t understand why your system has pumps. If your tanks have fwd and aft fuel line nipples at the bottom it might be possible to connect them for gravity feed based on the current drawings. Either that or all the kits used pumps prior to the late 90s. Dunno.

Yes, We did identified the failed item. And I do agree that simple is better. A passive gravity feed system would be more desirable, and as is mentioned above, latter versions use gravity feed. Early installations required the transfer pumps.

Just finished replacing both the right and left Monarch Aux tanks in a 182D due to radial cracks in the tank bottoms radiating out from the low point sump drains. Both tanks were leaking around the sump drains and the reverse thread drain fittings were corroded in place. Full tank removal to replace the sump drain valves identified the otherwise unknown radial cracking problem. Luckily found a set of replacement tanks, from another flyer who could not find fuel transfer control system parts, but held onto the tanks for someone else to use.

I have the old control head, and a pressure transducer from the prior installation. Unsure if they work.

Would like to know the brand and model of the pumps, to be able to locate replacements. Mine are un marked.

I do have the complete installation instructions if someone needs a copy.

Hi Brian,

I believe these are the pumps:

https://carterengineered.com/electric-fuel-pump-p60430

You wrote in your post: "I do have the complete installation instructions if someone needs a copy."

Do you mean the instructions related to the old style aux tank setup with the 2-button controller? I have this installation on my 1955 Cessna 180 - 2x 18 gallon Monarch tanks with the pumps and control head in the panel. One of the yellow lights on the control head lights up for a few seconds (eventually goes out but worries me). I'd like to gather as much information as I can before it ever goes south.

Thanks,

Don

I can't add much more, but I have a set of Monarch aux tanks in my 185, allows me to have about 93 gal useable with 100 total.
Have always worried about the Monarch control panel but so far it has worked fine except once a couple of years ago. Mains were down below half and neither tank transfer light would come on. They always come on for maybe 6-10 seconds then go out I toggle them back on and they stay on. I think that's part of the overflow prevention. Was close to destination so no big deal and it worked fine next day. I always test it when on a flight I might need them early in the flight just to be sure.
Tom

I have now experienced failure on my second control head (obtained from Ontario scrap yard) . Does anyone out there have a functioning control head?
Is it safe to simply hard-wire the pump to a toggle switch and time the transfer (42 mins for 17 gals) from the aux to main tank? Seems like the best solution and much simpler.
My 56 C-180 performed well for 30 years with control heads but do not want another failure en-route.
Blue skies angus