Originally Posted by
1QwkSport2.5r
You should never ever need to seal any part of an engine that uses o-rings to seal it. Period. If the needle moves on its own, replace the o-rings. Viton and silicone o-rings can be found at theoringstore.com.
So so many people do dumb things to their engines thinking they’re doing some good, but not knowing the reasons for the problems they’re having and the correct way of fixing them makes it that much more difficult. O-rings dry out and shrink - usually black rubber is used on the needle valves themselves. The problems with shrunk o-rings is needles moving on their own and fuel leaking OUT under high throttle. Air doesn’t leak in. Air leaks will manifest themselves in erratic ways. Most of the time, “air leaks” are actually poor carburetor settings.
on this i guess we are going to have to agree to disagree, its not so much to seal the engine that people RVT and or threadlock the MSN, its the fact that for 99% of the people that run them, do not ever adjust the midspeed needle. and as we know any metal on metal threads get threadlocked to avoid backing out. if its not going to be adjusted anyway it there is little reason to have to have it readily adjustable (i.e. need for an o-ring). and some people were having the issue of it backing out during or shortly after the break in period
i know plenty of people that are quite happy with their axial engines, seems you either got one that will last for quite a while or you had one that would die almost immediately.
Ive only had one engine that the backplate would not seal correctly on and so i did seal that one. to generalize that it is never an issue is kind of a closed minded way to view it imo, and for some after doing this it seemed to correct the issue, so i guess good on them. Most do it for no reason, but its not something i would recommend doing unless you have determined that it is an actual issue.