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Some general maintenance tips from Mike Busch

here

Standard stuff but I think worth posting.

Administrator
Shoreham EGKA, United Kingdom

My problem has always been with getting an estimate. Almost every repairman, no matter the trade, hates to give such an estimate cause they never know what problems they may encounter after starting the work.

Im going to have to have my mags OH as per scheduled hrs which everyone one Ive talked to said it is required. Im going to ask for a quote for R& R and overhaul. Im wondering if they will do it. By the way This is a pretty straight forward out and in. I know the points have to be replaced and a NYLON gear but I wonder what else is done during a Mag Overhaul?

A side issue I have with shops and manufacturers is the, Overhaul. Especially with avionics. You get something overhauled and you expect all the parts in it to be replaced when actuality only a repair is done, the components checked, and then yellow tagged as overhauled. But the price, even if only1 resistor was replaced will reflect as if everything inside the unit was replaced.

KHTO, LHTL

C210_Flyer wrote:

My problem has always been with getting an estimate. Almost every repairman, no matter the trade, hates to give such an estimate cause they never know what problems they may encounter after starting the work.

The problem with a “blanket” , all-in" estimate is that you will end-up paying for stuff that might not be needed. So the REAL problem is the client {you] will look at the estimate and say it’s too f’ing expensive ! It’s not reasonable to expect a shop or repairman to basically “bet on” the condition of the whatever in question, and of course they don’t want to get upside-down on the job either.
C210_Flyer wrote:

This is a pretty straight forward out and in. I know the points have to be replaced and a NYLON gear but I wonder what else is done during a Mag Overhaul?

Mag overhauls are a very well known quantity. Send yours to a BIG reputable shop, pay the flat rate, no surprises with that.

C210_Flyer wrote:

You get something overhauled and you expect all the parts in it to be replaced when actuality only a repair is done, the components checked, and then yellow tagged as overhauled. But the price, even if only1 resistor was replaced will reflect as if everything inside the unit was replaced.

Your expectations are not reasonable. The FAA spell it out in very simple terms and what you just described is “New” , not overhauled.

Here’s an excerpt from FAA AC 43-11, Cng 1 :

A major overhaul consists of the complete disassembly of an
engine. The overhaul facility inspects the engine, repairs it as necessary, reassembles, tests, and
approves it for return to service within the fits and limits specified by the manufacturer’s
overhaul data This could be to new fits and limits or serviceable limits. The engine owner
should clearly understand what fits and limits should be used when the engine is presented for
overhaul. The owner should also be aware of any replaced parts, regardless of condition, as a
result of a manufacturer’s overhaul data, SB, or an Airworthiness Directive (AD).

(My emphasis)

Last Edited by Michael at 21 Feb 10:58
FAA A&P/IA
LFPN

From the article :

1) Chose the right shop—one that’s comptent, communicative, and cooperative.
2) Insist on a written discrepancy list and estimate before approving any work.
3) If it ain’t broke, don’t let them fix it.
4) Don’t let them fix it until you’re sure what’s wrong.
5) Don’t overkill the problem.

1) Unfortunately, this is becoming extremely difficult as the number of GA specialty shops has shrunk considerably in the last couple of years.

2) A must, and clearly part of “communicative” in " 1)", but remember this takes time and a reliable, concise & detailed estimate will require several hours of investigation otherwise expect a “blanket” estimate that will basically be a CYA for the shop. I use another approach: Give the shop a couple of hours to inspect, test & troubleshoot the problem before nailing down a course of action and price for it.

3) Couldn’t agree more, in fact I would add that if it ain’t broke and someone tries to fix it you can bet it will be !

4) That’s why point 2 is such a pain ! How can you expect a precise estimate if the shop hasn’t conclusively determined the cause ?

5) This goes hand-in-hand with point 3 .

Last Edited by Michael at 21 Feb 11:13
FAA A&P/IA
LFPN

1) This is why I use Quality Aircraft Accessories in Tulsa, Oklahoma, for all component overhauls.

I have had so many bad experiences with UK firms I would not touch anybody in the UK. I even got a KI256 overhauled and when it was done (6 months later!!!) they said “sorry; we can’t do any paperwork anymore”. This was an EASA 145 company! You could not make it up. A complete joke.

Plus I am in touch with so many pilots so I hear a lot of stuff which one could never post. And most people would not post the name of a bad company, in case the company sues. Even in the worst cases the name doesn’t get mentioned.

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

I have had so many bad experiences with UK firms I would not touch anybody in the UK.

+1, for the whole of Europe.

I buy EVERYTHING in the US with one exception: engine oil.

100% of all the accessories overhauls/exchanges/repairs are sent to the US.

Last Edited by Michael at 21 Feb 14:40
FAA A&P/IA
LFPN

Better make sure you never need a Trig unit repaired then as they’re based in Scotland, or perhaps a Garmin repair done in Europe, as they all go to Southampton and are fixed by European technicians!

Last Edited by wigglyamp at 21 Feb 15:38
Avionics geek.
Somewhere remote in Devon, UK.

< cynical >
No worries. People who can afford such high principles like

I would not touch anybody in the UK

will not use stuff like Trig’s anyway – it is made in Europe, it is cost effective, it has good support, it absolutely cannot be any real good!
< / cynical >

EBZH Kiewit, Belgium

C210_Flyer wrote:

Especially with avionics. You get something overhauled and you expect all the parts in it to be replaced when actuality only a repair is done,

Michael wrote:

C210_Flyer wrote:
You get something overhauled and you expect all the parts in it to be replaced when actuality only a repair is done, the components checked, and then yellow tagged as overhauled. But the price, even if only1 resistor was replaced will reflect as if everything inside the unit was replaced.
Your expectations are not reasonable. The FAA spell it out in very simple terms and what you just described is “New” , not overhauled.

It is a classic case of being taken out of context. Especially with avionics in mind. We all know about the engine overhaul double speak. Where serviceable or within limits are reused. As an example, they will continue to overhaul your Cyl until one day even though it was within tolerances but due to thermal cycles the metal will fatigue crack and cause catastrophic cyl loss. Today most owners now know enough, to reuse only their own cyl whose life’s history and number of runs they know . Most would not overhaul a cyl more than once. Smart owners opt for new each time.

In my statement I was referring to mostly Avionics and their servos but you can put the following into the heap as well: starters and alternators. I had an STEC pitch servo overhauled 2010 and here it in 2015 it crapped out again. TT about 600 hrs. Some overhaul.

The fact charges a fortune to ck to see whats wrong and then bangs you for the repair which is sometimes only a less than an OVH unit which is then that I wonder exactly what was overhauled in the unit they are selling you.

As far as European work I would definitely use Dascher (sp?) for my overhaul of my engine. In my mind German quality when it comes to machine parts are still at the top. The question is with VAT and the Euro/$ and the labor rates can I afford it. However if the world is being supplied by only 1 source of say, hydraulic Lifters and if they manufacturing crap then no matter who puts your engine together you will be screwed.

But thats getting off topic. I dont understand how you can get an quote for a job when they have to find the problem and hope it is the right diagnosis. Who pays for the time it takes to track down the problem? You can only get a quote for a fix after you know what is wrong. What happens when you get a quote and then ok the repair only to find out it still dosent work? Is it warrantee work at that point and do you then hold them to the original price quote? I’ll wager they wont want your your work after that.

KHTO, LHTL

The problem for the maintenance company is knowing how far to go in initial diagnosis before presenting an estimate for a repair, knowing that the customer is looking normally for a cheap and quick fix. Something like loss of vacuum is really simple – failed pump, sheared drive, blocked filter etc, so fairly quick to diagnose and present an accurate quote.
However, if you have a defect like porpoising in pitch on autopilot, then it becomes much more complicated. You could have a stiff flying control bearing, tight pulley, wrong cable tensions, weak servo, slipping clutch, faulty gyro, defective computer etc. So who should pay for the diagnosis and how long should be spent before getting the customer’s agreement on a potential component change? There’s no simple answer and often the maintenance company ends up writing off fault-finding time which should really be chargeable.

Avionics geek.
Somewhere remote in Devon, UK.
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