OS 21TM - Seal it or not?
10-24-2017, 06:19 PM
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OS 21TM - Seal it or not?
Got a brand new OS21tm sitting on the bench. Seal it or not before install? If so, with what?
Last edited by rcfan450; 10-24-2017 at 06:27 PM.
10-25-2017, 04:37 AM
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That's the way I was leaning towards. The only reason I was considering it was cause the 3.3 traxxas engine I pulled had engine leakage issues. It was about the 9th RC car engine I've had over the years, first one with leakage issues though. I'm thinking just run it!
10-25-2017, 08:31 AM
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I couldn't ever figure it out. I dissected it, sealed it putting it back together, checked gas tank seal, gas lines, air intake, exhaust... everything. Couldn't figure it out. It wouldn't hold a tune for anything. Never had an engine act like that. Bought it used so I don't know how it was treated prior, it never ran great really. So I gave up on it, bought this OS (which I've heard lots of good things about), and just wondered if I should bother sealing it from the getgo or not. I have heard of guys who won't run an engine at all w/o sealing it. If I've ever had reason to seal a motor, it was this last motor I had. But if it'll help me avoid the problems I had with this last motor, I'll do it.
10-25-2017, 03:57 PM
#6
I've had a bunch of Traxxas engines. Most of the "air leaks" people spoke about was actually just due to improper carb setup. Tons of people are told via instruction manuals that a 1.0mm idle gap is normal and that is the heart of nearly all tuning problems.
If I have an engine that won't tune right, the first thing I check is the fuel system and carburetor. If that checks out, then checking the piston/liner fit is next. A poor fitted piston will cause the engine to not idle right and nearly impossible to tune. A properly setup engine will sometimes weep a little oil from the front bearing, but it shouldn't be much and is normal.
If I have an engine that won't tune right, the first thing I check is the fuel system and carburetor. If that checks out, then checking the piston/liner fit is next. A poor fitted piston will cause the engine to not idle right and nearly impossible to tune. A properly setup engine will sometimes weep a little oil from the front bearing, but it shouldn't be much and is normal.
