912 Magnetic Plug

[LimaMike08]

Hi,

 

I am having trouble removing the magnetic plug on a rotax 912.

 

I am worried about how much force I am putting into it (and as yet it hasn't budged). Can anyone advise?

 

 

[HEON]

There has been a "new" type of nut put out by Rotax...do you have it?

 

A "sharp" hit is often required to reduce the binding...Not with steel...Brass/bronze rod required.

 

Maj, your imput please.

 

Bluearsefly, just saw your airfield! Visit hanger M to see new nut on my Speed! (small world). Your trike photo did not ring a bell.

 

 

[LimaMike08]

Hi Heon,

 

Thanks. I hope to get out to the air strip towards the end of the week. I have just moved to Warwick and have been waiting for the weather to be kind. Seems to happen when I am away for work unfortunately.

 

 

[Guest Crezzi]

Hi,I am having trouble removing the magnetic plug on a rotax 912.

I am worried about how much force I am putting into it (and as yet it hasn't budged). Can anyone advise?

Try an impact driver if there is sufficient access. If not, a sudden jerk is more effective than steady pulling.

 

I think there has been a couple of changes to the plug - the most recent is a hex nut so, as Heon suggests, replace it with one of these

 

Good Luck

 

John

 

 

[Guest Maj Millard]

I too have had a drama with the allen keyed magnetic plug on my 912uls. After a chat to Wal on the subject he informed me there are three types that can be found. The internal allen key which is 6ml. An internal torq type which requires the appropriate tool. And the aforementioned external hex head type which appears to be the way to go, as you can get a spanner or socket on it.

 

However at $60 bucks a pop it must come with a Rotax guarantee that it is indistructable, and must be forged from only melted down Mecedes Benz crankshafts !!, with a magnet that was flown direct from the moon !.

 

Personally when I get a chance I will be sourcing an appropriat substitute at my local bolt shop, or other automotive source. Until then if you are upgrading to the hex-head (recommended) Bert Flood has them..........................................................maj...

 

 

[facthunter]

Over-tight drain plugs.

 

A sharp hit straight-on with a copper, brass, or aluminium flat ended drift is a good start, especially if there is a copper washer under the head which is slightly compressed by this method. If it is an aeroplane part, it is high priced. Rotax is never cheap. Nev

 

 

[HEON]

If I am not on field, phone number on hanger.

 

 

[Guest Maj Millard]

facthunter, that's all good as long as a previous owner hasn't used the wrong size allen key and stripped out the receptical, which is not hard to do. Not to worry, when I want the sucker out, it'll come out believe me !......................................Maj ...

 

 

[facthunter]

Desperate.

 

Yes I was trying to be gentle. Weld a bit of square onto it if you get desperate. There is always a way. there has to be. The show must go on. Nev

 

 

[Mc Guyver]

Yes I was trying to be gentle. Weld a bit of square onto it if you get desperate. There is always a way. there has to be. The show must go on. Nev

Make sure that you have also warmed the motor before trying to loosen the bugger:exclamation:

 

 

[facthunter]

True--

 

Having the motor as hot as, would be a good start. Also IF you are going to weld a bit of square on , it helps to prevent thermal shock. Jeez, don't use this as the normal way fella's, but I have resorted to it. Put the minimum of heat into the casting, from the weld as it is concentrated at one point. To do it properly, dismantle the part, and preheat it. It may become quite loose once heated. Nev

 

 

[dazza 38]

Has anyone used a heat gun? To heat the surrounding area on the block.It can help sometimes.Their was a great article in august 2008 in RAA magazine, about Rotax maintence, the aricle mentioned, basicaly what the guys above have mentioned. Give it a good whack before trying to loosening it.Cheers

 

 

[JG3]

Use a sharp cold chisel to put a good nick in the outer edge, in the direction of unscrewing. If that isn't enough to loosen it already, use a pin punch in that nick to knock it loose. Works a charm, without any damage anywhere. The plug can be reused, and the notch is already there to tap it loose next time as well.

 

JG

 

 

[pudestcon]

You mean like this - as per above post & my post #4Cheers

Dexter

I like the manicure Dexter:laugh: looks just like my nails. Can I have the contact details for your manicurist please?

 

Sorry, off topic but couldn't resist:helmet:

 

Pud

 

 

[Guest Maj Millard]

Fellas, They must have some huge burly Austrian at the factory putting these damn things in. They are just too tight from new. Obviously when you put it back in (after cleaning the magnet of course) put a small amount of antiseize on the threads, same as you would on spark plug threads, and it should not be a drama next time.You want it tight enough so it doesn't come out during operation, but there is no other reason that I know of why it needs to be super tight !. Rotax states the torque for it as 225 Inch Lbs (18.75 Ft Lbs) Personally I think they need to drop it a bit, as I believe 12 Ft Lbs should be plenty IMOP...Maj...

 

 

[Tracktop]

put a small amount of antiseize on the threads, same as you would on spark plug threads, IMOP...Maj...

antiseize? doesn't the Rotax manual call for heat transfer paste?

 

Had wondered about using antiseize as I usually use it eveywhere I can - better rephrase that - I usually use it on any nut or bolt threads that I can - sure makes the job easier next time.

 

 

[Guest Maj Millard]

Tracktop, We did this one pretty good in a previous post. Rotax calls it heat transfer paste, every body else calls it Anti-seize. Comes in various colours, common in GA to use nickle antiseize which is sort of dull silver. Put some on some plugs today in fact. You certainly wouldn't need heat transfer paste on that plug...............................................Maj...

 

 

[Dieselten]

Try spraying some electronics freezing-spray on the recalcitrant plug and see if that helps shrink it slightly in the threads and makes it easier to dislodge.

 

 

[wanabigaplane]

whack - WHACK

 

US$35 from Leading Edge - ask someone going to Oshkosh to bring one back.

 

I purchased the right driver bit locally. Tried everything - actually put a twist in it!

 

I had to take the exhaust off to get a direct hit with a brass drift. It took an unbelievably big whack to loosen it.

 

The heatsink paste is for spark plugs to transfer heat. I bought some small sample sachets from Leading Edge, only to find it seems to be exactly the same as that you get in the 5 gram Unick tubes from Jaycar in the $6 range. This is NOT an anti-seize compound, so I plan to check the plugs more often. Jack:hittinghead::hittinghead:

 

 

[Tracktop]

Does the anti seize stuff transfer heat????

 

I spoke to Wal at BF recently about how critical the use of heat transfer paste was on my engine. His opinion was that the 80hp is usually fine without heat transfer paste ( well so long as it was used in the previous spark plug change so there was still some residual there ) but the >80 hp models needed it or the spark plugs can get overheated due to not being able to transfer the heat out quick enough. So I read from my discussion with him that the heat transfer paste is not there to as an anti seize medium ( a function also nice to have, I understand ) but to ensure there is good heat transfer out of the spark plug for the spark plugs sake.

 

As an aside, he also said it was important that the heat transfer paste was the non hardening type.

 

 

[Guest Maj Millard]

Not wanting to butt heads with wal as I trust his opion without question.

 

The heat range of a plug last time I was taught determines "the ability of the spark plug to dissapate, or transfer heat away from the plug tip"....this is achieved at different levels by varying the length of the ceramic conductor around the center post, amoungst other things.

 

So therefore you are transferring heat from the steel plug body, into the (water cooled) alloy heads which then dissapate it via the coolant and cooling fins.

 

I can see how a heat transfer paste would possibly assist, but it is going to happen also without it. The main reason for using anti-sieze on plug threads is so that the steel doesn't corrode with the alloy (dissimiliar metal corrosion), making the plug almost impossible to remove, or worse still pulling out any helicoil with it, as it does so, or even the standard alloy threads.

 

Most GA type engines are Helicoiled as standard, to increase the strength of the thread. You never know when somebody has cross threaded a 912 or Jab spark plug hole, and fixed it with a Helicoil either. Then you better hope they used something on the threads !!........................................................................Maj..