Magneto 500hr check/overhaul

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Flying John
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Magneto 500hr check/overhaul

Post by Flying John » Thu May 10, 2018 6:27 pm

Can anyone enlighten me and show me the official rules for magneto overhauls for Permit Aircraft at 500hrs.

Is it the same as it is for CofA types, can it be done yourself with an overhaul kit perhaps, or do we have to spend close to £500 to send them to Mclarens for a certificated overhaul.

Advice welcome.

John
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tnowak
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Re: Magneto 500hr check/overhaul

Post by tnowak » Fri May 11, 2018 8:33 am

I don't think anything is mandated but is probably a good idea.
Some magneoto manufacturers (Slick) recommend inspections at around those hours.
LAA engineering can advise if you can do the work yourself with oversight by an LAA inspector etc.
Tony
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mike newall
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Re: Magneto 500hr check/overhaul

Post by mike newall » Sat May 12, 2018 10:11 am

As it is a Service Bulletin and not mandated, it is optional on either certified or permit aeroplanes.

If all is well and you are running and starting well, carry on and spend your money on extra avgas !
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dmcnicholl
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Re: Magneto 500hr check/overhaul

Post by dmcnicholl » Sun May 13, 2018 8:40 am

If it's a Bendix I agree with Mike Newall. The relevant Service Bulletin is SB643B wherein it states "...must be inspected every 500 hours..." but that it's written into a SB not an AD makes it discretionary not mandatory.

No idea about other magneto manufacturers, though.
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Leesr
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Re: Magneto 500hr check/overhaul

Post by Leesr » Sat Jun 02, 2018 9:09 pm

It's a good idea, whether mandated or not for LAA types. Bearings corrode, points wear etc etc.

I have just overhauled a pair of Eisemann mags of unknown time since last looked at. They were in fair condition, but the impulse spring on one of them was about to let go, and although the bearings were perfect, the grease was about done. I had to replace a coil due to melting of the plastic encapsulation, so that was about to go as well.

I inspect a few LAA aircraft, the owners of which I advise to have a 500-hr inspection carried out when due.
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mike newall
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Re: Magneto 500hr check/overhaul

Post by mike newall » Sun Jun 03, 2018 10:30 pm

I will elaborate on my first post then....

If your magnetos are ancient..... and come up to 500 hours, then yes, get them looked at.

If you do lots of hours and they achieve 500 hours and are still good - crack on :lol:
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Seanjd
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Re: Magneto 500hr check/overhaul

Post by Seanjd » Sat Jul 28, 2018 6:52 pm

Mine had done 527hrs and appeared to be all ok, but my inspector suggested I get them overhauled.
One had a cracked case and had to be replaced, so I am glad they where done.
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pgpeal
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Re: Magneto 500hr check/overhaul

Post by pgpeal » Tue Jan 18, 2022 9:20 pm

I asked LAA Engineering just this question about our Slick mags, as follows:
We have a low-hours IO360 in our Vans RV8. The Slick magnetos will reach their first 500 hours late this year we reckon.

Can we do the IRAN ourselves? If not or if better to have an expert look inside, do you have a list of people known to be good at inspecting Slick magnetos please?

I got the following really helpful reply from Jerry Parr which I post with his permission:

The first thing to remember is that the 500 hour inspection is not mandatory on your aircraft, regardless of what the manufacturer and others might like to say.

As the 500 hour inspection requires the internal inspection and subsequent refitting of the magnetos, this work will have to be signed for by an LAA inspector as these maintenance tasks fall outside what is allowed under ‘pilot maintenance’. Further details on this can be found in LAA Technical Leaflet TL 2.05.

It should be remembered that the 500 hour inspection is just that – an inspection and not an overhaul.

Many of the CAA approved engine overhaul facilities (such as Nicholson-McLaren Aviation or Norvic Aero Engines) will carry out the 500 hour inspection for a (pretty reasonable) fixed price.

If you carry out the inspection yourself then you would really need access to the appropriate manual and it may not be possible for you to do all of the inspection and functional tests.

Whilst an inspection may show worn or pitted points or cracks in the distributor gear and other such physical inspections, ignition coils either work or they don’t, so the inspection will not be able to tell you how ‘good’ the coil is.

In my experience, Slick magnetos are extremely reliable and failures are normally total and occur between flights, ie it was fine on one flight and is completely dead on the next. Far more common is a gradual reduction in starting performance where the impulse couple spring has weakened.

My personal advice (based on maintaining many dozens of Slick ignited engines over many years) would be to remove the magnetos and send them off to a company such as NMA and have them inspected professionally.

If you really want to do them yourselves, I would suggest not doing them both at the same time and perhaps staggering the inspections by 10 hours of flight time. This would reduce the likelihood of making a mistake on both magnetos at the same time. As mentioned, this would have to be carried out under the supervision of your LAA inspector.
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coxargus
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Re: Magneto 500hr check/overhaul

Post by coxargus » Wed Jan 19, 2022 9:42 am

Try Soar aviation - Steve Hodge 07890 519 924 [email protected] if you would like a professional to look at it - reasonably priced too!
Frank
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LSHAvenger18
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Re: Magneto 500hr check/overhaul

Post by LSHAvenger18 » Sat Feb 19, 2022 11:15 am

Steve at SOAR has a wealth of knowledge, nice guy too.
He has provided me with a top class service over about 18 months.
Including magnetos and an A65 top overhaul.
Simon
Simon Heighway
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