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Rotate spark plug thread heat compond

Plug Thread

I can't believe that what is done on lycomings would not be sufficient for your Rotax. Concept is all the same. Use a copper-based anti-seize compound on spark plug threads starting two full threads from the electrode.
 
Spark plug compound

Rotax plugs require the heat transferr paste, you can get small amounts at Lockwood Aviation Sebring ,Fl for a very reasonable price. A very small amount is used. GL ben
 
Rotax spark plugs required thread heat compound that is listed at 146.00 a tube. Any suitable sub around.

You can find silicone heat transfer compound in small quantities for less than 10 bucks and that amount will last for several years.
 
I can't believe that what is done on lycomings would not be sufficient for your Rotax. Concept is all the same. Use a copper-based anti-seize compound on spark plug threads starting two full threads from the electrode.

Copper based anti seize compound is for unplated, black, steel based threads on the spark plugs.

It is NOT for tri valent plating sacrificial finished NGK plugs that go in a Rotax 912.

https://ngksparkplugs.com/en/resources/5-things-you-should-know-about-spark-plugs
 
Search Amazon for "thermal paste". You can order whatever size container you want of white silicone thermal paste... dirt cheap, and the little 50 or 100g jar I bought will be a lifetime supply for at least one airplane... maybe two.
 
Roger,

FYI, please edit the title to this thread. None of the Rotax guys will be able to find it, using the search function [as is]. Having the spell checker set to "auto correct" is not always your friend! :eek:

Charlie
 
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How about $61.00 per 150gr tube?

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https://www.amazon.com/SILICONE-PAS...s=Wacker+Silicone+paste&qid=1569251960&sr=8-2
 
Thermo paste

Most heat transfer paste products are rated up to 300 degrees. I use Silicone Solutions #SS-240. It is rated for over 600 degrees. Non hardening. It comes in a 3 oz squeeze tube and is enough product to last a few life times. About $20/tube. I use it for both Lycoming and Rotax engines. The key is to use it SPARINGLY!
 
Rotax spark plugs required thread heat compound that is listed at 146.00 a tube. Any suitable sub around.

I was just talking to my buddy yesterday about spark plug anti-seize. I did a little research today on it because I need to buy (something) to keep on my shelf.

The Wacker P12 thermal paste is what is recommended (see Page 16 or 19 of the Rotax Illustrated Parts Manual for the 912 or 912iS engine). Here is the datasheet for it. The main characteristics for this silicone paste is the operating range (-40 to 200C) and thermal conductivity (0.81W/mK). It is made as a heat-sink paste for electronics, not an anti-seize paste for engines (though it does have some lubricating qualities). This posting seems to indicate that factory testing shows it "reduces spark plug temperature by 10C", though I was unable to find an authoritative source.

That said, Lockwood aero seems to have Rotax Part #897186A listed, which is a MG Chemical paste. I'm not sure where this A part # came from, as I don't see it listed in the latest Rotax manuals. Perhaps Lockwood realizes that Wacker P12 is hard to find and uses something else that they found to be adequate.

One that was mentioned earlier was MG Chemical 860.. which has slightly less thermal conductivity (0.66W/mK); SS-240 is 0.735W/mK; . Better than nothing, and probably more than adequate Search DigiKey for other options.

All that said, Hisco lists the Wacker P12 for it for $33 -- which is still theft, but not the grand larceny that CPS performs @ $164.
 
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