BeechTalk - BT - Needed: Early Malibu Hydraulic Pressure Guage

Username Protected · **Posted:** 19 Jun 2020, 13:12

I am sort of "outing" myself prior to a formal announcement, but I have an urgent maintenance issue. It seems as certain as death and taxes that days after you purchase a new (to you) plane something complicated / expensive / rare will break. I am following that trend well.

I am looking for a source for a new / overhauled / suitable replacement for the hydraulic pressure gauge in a 1984 PA46-310. It's Piper part # 598-542. It hasn't been made in decades. I have tried all of the usual salvage yards and supply houses. Spruce has one that might be a good replacement, but they are on back order until July.

Any advice would be greatly appreciated. I will cross post to MMOPA as well.

Username Protected · **Posted:** 19 Jun 2020, 13:54

Partsbase shows these 2 sources although from past experience I'd almost bet they don't have stock.

598-542
Western Aircraft, Inc.
800-777-4926
Premier Vendor
INDICATOR: PRESSURE,HYD NE 1 RFQ ID, United States

598-542
AFR Enterprises
714-784-5060
FN 1 RFQ CA, United States

Username Protected · **Posted:** 19 Jun 2020, 14:25

If its the same gauge as on the piper aerostar's of similar vitage, you might try aerostar aircraft, or one of the aeorstar salvage people..

Top right corner of this picture:
https://photos.app.goo.gl/ohKawUinT8ri6JtZ8

Username Protected · **Posted:** 19 Jun 2020, 16:57

Username Protected wrote:

Any advice would be greatly appreciated. I will cross post to MMOPA as well.

have you talked to Kevin Mead?

Also this seems like an excellent opportunity for an owner produced part and/or an A&P willing to sign off a minor alteration if this is truly just a pressure gauge with no other function.

Username Protected · **Posted:** 19 Jun 2020, 19:45

Username Protected wrote:

Any advice would be greatly appreciated. I will cross post to MMOPA as well.

have you talked to Kevin Mead?

Also this seems like an excellent opportunity for an owner produced part and/or an A&P willing to sign off a minor alteration if this is truly just a pressure gauge with no other function.

Username Protected · **Posted:** 19 Jun 2020, 22:45

Thanks all ! Even as a brand new Malibu owner, Kevin was my first call. His response was along the lines of “That stinks. Those are impossible to find”. Exploring a couple of overhaul shops that claim they can fix the manufacturers part number. If that doesn’t pan out, this will definitely be an owner produced part. No real other choice.

Username Protected · **Posted:** 20 Jun 2020, 17:15

Check out Arizona Aircraft. They had a pressure switch that I recently needed.

Username Protected · **Posted:** 22 Jun 2020, 14:58

I forgot about the 'repairs capability' on Partsbase, came up with this.

598-542 Otto Instruments Service
909-930-5800
HYDRAULIC PRESSURE GAUGE CA,United States

12/30/2019

Username Protected · **Posted:** 22 Jun 2020, 16:47

Username Protected wrote:

Thanks all ! Even as a brand new Malibu owner, Kevin was my first call. His response was along the lines of “That stinks. Those are impossible to find”. Exploring a couple of overhaul shops that claim they can fix the manufacturers part number. If that doesn’t pan out, this will definitely be an owner produced part. No real other choice.

Substituting a part is not really owner produced. But it may qualify as a minor alteration if the replacement gauge has PMA or TSO.

Username Protected · **Posted:** 22 Jun 2020, 18:26

Username Protected wrote:

Thanks all ! Even as a brand new Malibu owner, Kevin was my first call. His response was along the lines of “That stinks. Those are impossible to find”. Exploring a couple of overhaul shops that claim they can fix the manufacturers part number. If that doesn’t pan out, this will definitely be an owner produced part. No real other choice.

Substituting a part is not really owner produced. But it may qualify as a minor alteration if the replacement gauge has PMA or TSO.

Username Protected · **Posted:** 22 Jun 2020, 21:47

Username Protected wrote:

Substituting a part is not really owner produced. But it may qualify as a minor alteration if the replacement gauge has PMA or TSO.

Even if it’s not pma/tso... it’s a pressure gauge. This is a well understood part. Is there anything special about aviation pressure gauges

Username Protected · **Posted:** 22 Jun 2020, 23:45

Username Protected wrote:

The original is part of the TC. So to consider it a minor it needs to have the pedigree.

Mmmmmm. No.

Username Protected · **Posted:** 23 Jun 2020, 09:03

Username Protected wrote:

The original is part of the TC. So to consider it a minor it needs to have the pedigree.

Mmmmmm. No.

Username Protected · **Posted:** 23 Jun 2020, 09:22

Major alteration means an alteration not listed in the aircraft, aircraft engine, or propeller specifications -

(1) That might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or

(2) That is not done according to accepted practices or cannot be done by elementary operations.

Minor alteration means an alteration other than a major alteration.

I have not seen this hydraulic gauge. It is possible it has some special characteristics I'm not imagining or provides some sort of feedback mechanism to the system. I am assuming it is a mechanical gauge that simply measures fluid pressure and moves a needle. In that case nothing about it breaches the major threshold.

Signoff would be. "Removed p/n XXXX, installed John Deere p/n YYYY. Ops check good."

Username Protected · **Posted:** 23 Jun 2020, 09:37

Username Protected wrote:

Major alteration means an alteration not listed in the aircraft, aircraft engine, or propeller specifications -

(1) That might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or

(2) That is not done according to accepted practices or cannot be done by elementary operations.

Minor alteration means an alteration other than a major alteration.

I have not seen this hydraulic gauge. It is possible it has some special characteristics I'm not imagining or provides some sort of feedback mechanism to the system. I am assuming it is a mechanical gauge that simply measures fluid pressure and moves a needle. In that case nothing about it breaches the major threshold.

Signoff would be. "Removed p/n XXXX, installed John Deere p/n YYYY. Ops check good."

So we agree it could be a minor, we just don't agree that the John Deere part can be installed.

How many A&Ps would install your John Deere part to replace a part that is part of the original TC?