Originally Posted by Luke W
If everything is tight and you still hear that sound, that's not good. I've heard engines have that same spinning metal sound, and it means a bearing is going bad. With the way you're describing the sound, I'm guessing that's what it is, I just can imagine it would happen this early. However, if you ran the engine too lean in break-in, that's probably what caused it. That same exact engine was my first racing engine and the main problem I had with mine is that the low speed needle was so rich that it wouldn't start. Other than that, nothing needed to be tweaked, for break-in at least...
Oh no... but i just got the engine brand new.
The guy at my LHS set the HSN so lean about 1 turn and ran about 3/4 tank before i get it home. I do question him on why the engine require such a lean setting brandnew and he say it normal... anyway, he did had a hardtime keeping it running at more the 2 rounds HSN from close.
i try to ran it at 2 turn but not so smooth and i reduce it to 1.1/4 turn and it works normal but abit lean. ran that for 1 tank
Day 3 (yesterday)
I finally gets it smooth running by leaning the LSN because like yours, the LSN are too rich to begin with from default setting. I also set the HSN to +/- 1.5 to 1.3/4 turn... running richer then he LHS guy's setting The sound thingy came at about 2nd tank for the day. In all i only ran 6.5 tank breakin in since i got this engine. The sound appear on the 3rd tank If what you say is true, a bearing going bad,... do you think i'm warrant for a refund or exchange? Will running the engine back to very rich setting help the situation?
Ok, let me better describe the sound... you know the 'white noise' sound you get from your TV set when there's no signal? imagine that type of sound but more metallic kind and softer. You can barely hear it behind the RPM sound but once your ear detect it, it become obvious to your hearing sense. It's not the usual engine's 'empty' metal sound you get when your RPM are low on idle, it's kind of buzzing sound type. Hope my explanation works. anyway, i'll run it later today when i get home and i'll try top record it.
Usually when the engine is running, there should only be the RPM sound and not any other sound right? Will the exhuast produce funny sound even on idling? i'm using OS exhuast too.