Trouble Shooting • 82 cb650sc cylinders 1 & 3 not firing
- Tue, 13 Feb 2018 04:41
I swapped the plugs and wires on each coil (1&4, 2&3) with no change ruling out those components and bad spark.
I DO have vac leaks at all boots but interesting thing I noticed is on 1&3, the trouble pair, carb spray makes engine rev and headers hot yay, but ironically the 'good' pair, 2&4 stall the engine with carb spray. I also swapped boots between the two pairs and they still behaved the same.
I dialectic greased all the connections except the ones with the shrink tube but they all looked really good.
I tried setting idle speed but 1&3 pilot scews aren't affecting the rpms at all, so I couldn't really finish that and adjustments overall didn't seem to make much difference, except with #4 which actually fires better than #2, bit hotter on the header and makes noise against my hand at the tail pipe, actually both 3&4, especially 4 pops on my hand whereas as 1&2 very slightly.
I had trouble with the timing as after searching the manual an online it still never became clear which mark is for timing, the T under the single mark or the F under the double mark? You might think T for timing but then the book shows the fixed mark lined up with the double marks over the F. So I just did the simpler "static" method. But I'd like to do the dynamic one with the light gun and do it right with the other advance something or other test. I'm new at this. Especially if it's more thorough. Tho the static method is easy and if it's accurate over a timing light I'll take it.
I did the valve clearances correctly but only after a lot of trial and error, so IDK if damaged the head. I would doubt it since I cant imagine setting the clearances on the lobes could cause anything make excessive contact with too much clearance so maybe less contact could mean more loose parts and shaky unstable movemet, idk, but I run it probably a few minutes after setting clearances incorrectly(it took me a while to learn how it all worked).
Sorry for all that but that's what it's been. So what do you think?
Statistics: Posted by juntjoo — Mon Feb 12, 2018 6:00 am
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