Spark Plug thermal heat paste

This always bothered me a tad but now I feel it’s time to seek an answer as a result of the latest Rotax SB 912-079 release. The new SB reminds us (twice) to apply the “…correct amount…” of compound to the spark plug threads to prevent possible piston damage. Piston damage is scary stuff.  Yet the MML provides no such quantity.  It provides subjective application quantity advice such as “apply sparingly” and “small amount”.  These are not measurable quantities. Where has Rotax published the correct amount of heat conduction compound that I should apply to the spark plug threads please?

The paste transfers heat (approx. 40F) from the plug to the head to help stave off detonation. The operating high temps allowed by these two products are up around 395F.  Apply it to the middle of the plug threads. Do not glob it on. Just fill the threads. It will spread by itself as you thread it in. Many people I know use MG 860-150 thermal paste. It's an equivalent of the Wacker and much easier to come by.

https://www.rotax-owner.com/en/videos-topmenu/rotax-minute/399-2-oil-inj247

https://www.amazon.com/MG-Chemicals-860-150G-Silicone-Transfer/dp/B005DNQWQU/ref=sr_1_1?crid=1657LROWSXUTY&dib=eyJ2IjoiMSJ9.D3T4Sq7ATTEOs6XXy11tTg.de5LSEMabZ858NFJYImnRoVl-BasqI_dQaX9l6Q6ULQ&dib_tag=se&keywords=mg%2B860-150&qid=1731503305&sprefix=mg%2B860-150%2Caps%2C191&sr=8-1&th=1

Since you are only filling the gaps between the threads when it is torqued up, the amount needed is very small. As Roger says, just apply a small amount around the middle of the threads, then I try to wipe as much off with my finger, so the threads end up being only about 3/4 filled. When you remove a plug, if you notice a lot of the white paste globbed around the gasket surface, that is telling you that you used too much. The main thing of course is to keep the paste well away from the tip of the threads. Too much at the top/gasket surface just makes a mess.

Thank you all, I will. Now on to my original question, when will Rotax place the correct amount to apply (or how) in a technical manual or bulletin? Even a detailed description such as “fill the spark plug threads beginning three full threads from the electrode ending at the uppermost threads and wipe clean any excess” or similar. I’m just saying if you tell me a dab is necessary to preclude severe damage to my aircraft engine then please tell me in a  service document approved by Rotax how much and where to apply my dab of compound. 

he all.. i

Check the latest manuals, it is pretty clear.

Cheers