The 400 Comanche development and testing. The following makes interesting historical reading regarding the 400 Comanche.

by Calvin F. Wilson, Jr; director of Engineering Piper Aircraft Corporation.

The 400 by Walter Jamouneau.

There is more information in the book, "Piper Aircraft" by Roger Peperell.

Piper Service Letter 453 - concerns the engine mount refinishing.

Service Instruction 1444 concerns the Bendix S-1200 series magneto, a service bulletin [dealing with the retard breaker]. A good one to know about; I sent my mags out for OH and they came back without this attended to - how nice! The agency even argued about the existence of this bulletin.

400 PARTS DEPARTMENT

492-084 - FUEL SELECTOR VALVE

AKA 1H11 & 1H11-1

a little boring history. These fuel selector valve and strainer assemblies were originally manufactured by Airborne Mechanisms in Cleveland, Ohio.

Shaw Aero Devices here in Naples purchased the rights; subsequently Parker Hannifin bought Shaw Aero Devices in 2007.

I was contacted by Shaw a couple years ago when there were having difficulty with their new Twin Comanche valve; i assisted in a small way. when i asked in turn for a "favor", re parts breakdown on the 400 valve to possibly have replacement parts available, guess where that went. Parker [Shaw] manufactures the new SS valves for the twins; they make no mention of the 400 valve - I tried.

This one has an illegal modification, the addition of a spacer to accommodate the shorter Twin Comanche stainless steel bowl. I have the original bowls available, freshly cadmium plated. The SS bowl is not flat-bottom; this is better because it directs water to the drain instead of cornering it aft in the flat-bottom bowl. If you want this mod, do like the owner of this one did, install it yourself.

PA24-400 Fuel Selector Valve - shown assembled.

Problems to watch for. See the photo above; click on it for another more-detailed photo. If yours has seen the rigors-of mortis via the thoughtless application of such a crude devise as a vise-grip, you may be out of luck. There are no spare parts available as I mentioned previously. In this case you'll have to locate a serviceable valve or component to send for service. Don't let this happen to your expensive valve.

If your valve shows signs of becoming difficult to rotate [i.e. select another position] do not take this route as it will render your valve a very expensive desk-top "what's that?" device. Parker's current price for a new Twin Comanche valve is $3865; what would one cost that is not available?

If yours is transferring fuel [see the AD 79-12-08 and the SL-851 part A] or difficult to rotate positions, it's time to get it fixed. I can service your valve and provide a yellow tag referencing the SCSM service procedure, and these references mentioned.

For the Flap Cable Conduit Assembly P/N 494-660

Contact Webco Aircraft.

Sales Brochure - click above.

Here are a few before and after photos. Click on the photos below for more.

24569-000 before repairs.	24569-000 after repairs.

Induction housing assembly repair brochure; this is the air filter housing. This assembly is not terrifically durable and its condition diminishes over years of service. If you need this repair please plan ahead and warn me to get started on the one I have available exchange. I stay busy and probably won't be able to do yours quickly. I'll determine the repair cost when I examine your assembly. Don't let this get to the point where the repair is not economical; it has happened!

Nearly completed repair procedure - 400 induction housing components; 24569-000 and 24568-000. Still need to install the CamLock™ latch assemblies, and the alternate air door.

Induction housing assembly continued airworthiness brochure

Completed induction housing installed.

It's possible that by repairing and properly sealing this housing assembly [as part of the repair process], one might gain some manifold pressure due to reduced leakage. I can't confirm this but it makes sense to me.

NO STOCK AT THIS TIME

Airborne fuel pump 2B6-26, Piper P/N 757-431; part of fuel pump replacement kit P/N 760-791. Click on the photo above for another view.

If you still have the old Bendix pump, this is Piper's solution.

A few exhaust parts are available.This set is new old stock; when they're gone that's all folks! As of 01/2011 I have 2 sets remaining.

Click on the photo above for more exhaust components.

Here is the installation manual I include with the rebuilt mufflers; there are some tricks. I was able to get the Piper drawings for the mufflers but without dimensions; those missing dimensions were a clue. I measured an original pair of mufflers and came up with the right numbers. Now I have a drawing and have found a shop that has been doing a great job as you can see. I have muffler cores available for rebuild, but I do not stock the rebuilt mufflers. If you need one or the pair let me know and I'll have your order ready as soon as possible.

400 Comanche Boost Pump

• 400 Airborne pump [2B6-26] - this can be a difficult item to locate. 35 years ago Piper issued a replacement kit p/n 760-791 to replace the original Bendix pump . If you still have the original Bendix pump and need the Airbrone and the mounting bracket, call me.
• There is a 337 floating around for a replacement Dukes pump; I should be able to capture that as a solution for the non-available 2B6-26 core issue soon. This will allow installation of the replacement pump which can be purchased outright, thus bypassing the difficult issue of finding an Airborne core for exchange or overhaul..
• photo #1 - installation showing special mounting bracket
• photo #2 - end view identification
• photo #3 - plan view identification
• photo #4 - mounting bracket p/n 28080-000 included in Piper kit P/N 760-791. An owner produced part; you ask and I make it for you - $145.00

Nose gear door problem-solver; read this even if you don't know you have a problem with those doors.

This relay is used in the 400 Comanche for the 24-volt staring system. $200.00 each. New old stock; when they're gone you're out of luck.