quote:Is it OK to use oil in a clear tube that is fitted snugly into the spark plug hole for finding TDC?
Oil will leak out of the combustion area through the ring end gaps, but you can probably make it work.
If you make the check with oil, after you are done, pull all of the spark plugs and rotate the engine by Hand through several revolutions. Then crank the engine with the starter for 20 or 30 revolutions in order to get as much oil out of the cylinder as possible. Upon engine start up, be prepared for a big cloud of smoke. Better alert the neighbors that your garage is not on fire!!
You can just do a quick check of the timing marks by bring the #1 piston up on the compression stroke. Shine a flash light into the #1 spark plug hole and watch the piston as is comes up (as you rotate the crankshaft by hand). You can get very close with this visual check, close enough to see if the timing marks are off by a significant amount. If they are, then you will know that the balancer ring has slipped. You should be able to approximate TDC and set your initial timing for a start up.
John