Originally Posted by
kwhunter
After Run Oil
There is conflicting information from various manufacturers on how to treat an engine after it was run. Everybody recommends using an after run oil, however TRAXXAS advises using WD-40:
https://traxxas.com/support/How-Perf...-run-Procedure
whereas Novarossi is firmly against it:
Frequently Asked Questions | Novarossi World - NOVAROSSI WORLD
WD-40 is widely known as a water displacement product, but nobody (except perhaps the manufacturer) knows its composition. I doubt it has any oils in its formula
After I've read the TRAXXAS article, I used WD-40 on my Kyosho engine (even though it's not a Traxxas…) Next time I ran it, it seized on the end of the crankshaft on the sealing surface behind the front bearing; not a big thing and it's already fixed, but I wonder... was it the WD-40 or was it not?!
Lacking a proper "after run oil", now I'm using a 3-in-1 product called motor oil M-20; at least it is oil, and also has a strong odour (why?).
What do you experts think, what is your experience?
It is a good idea to use after run oil after each days running. Certainly if the engine will not be run for over a week. In certain parts of the country where it can be very humid, engines start to rust quickly without after run oil. No fuel is immune to attracting moisture when left inside the engine. A common problem I see causing bearing issues is rust inside engines. This can be avoided by using the right after run oil properly.
Don't put the oil in the glow plug hole, put it into the carburetor, and turn the engine over on the starter box for 3 seconds.
It is also very important to get any residual fuel out of the crankcase before you add the oil. To do this remove the fuel line, and start the engine until it doesn't want to fire any more. The engine will likely run for a few seconds as the residual fuel is being burned.
Regarding type of after run oil. Do not use WD-40. The WD, and any other petroleum based chemicals will make the silicone in some engines swell up, and detach. Our after run is completely silicone safe. Most labeled after run oils will be safe.