I need to find top dead center on my 1988 302. My 302 hasn't had a distributor in it for some time and I've changed the damper, so finding TDC will have to be done from scratch. I know that TDC is when piston number one is at the top of it's travel, but this happens twice during the 4 stroke cycle.....so the question is how to tell which time is the real TDC. My valve cover is off, so I'm ***uming that watching the rocker arms do their thing is the way to tell, but what should I be watching for with the rocker arms/valves?
Both intake and exhaust valves will be closed when your on the correct stroke for TDC on the power (when the plug fires) stroke. If you damper timing marks are different than stock you will have to determine when the piston is at top dead center. I use a piston stop made for this purpose.
Y-Blockhead is absolutely right. You can tell when both valves are closed because there will be no tension on the pushrods on that cylinder. A piston stop is a device which screws into the #1 spark plug hole and extends into the #1 combustion chamber. One rotates the crank in one direction until the piston hits the stop. Mark the damper where the pointer points, regardless of where it is with regards to the actual timing mark. Then rotate the crank in the opposet direction until the piston hits the stop and mark the damper in the same way as before. The point exactly half way between these marks is your actual top dead center. If it corresponds to the original timing mark, great! If not you'll need to re-mark the damper to reflect the new top dead center. Rotate the crank until the pointer lines up with your new top dead center mark, check to be sure both #1 pushrods are loose, insert the distributor in the proper position with the rotor pointing to the #1 terminal on the cap and you're ready to fire it up and fine-tune the timing with a timing light. Sounds complicated, but it's not.
ok....I've been out messing with it and I think I've got it pretty close to TDC. I pulled off the p***enger side valve cover and found the point on cylinder #1 where both valves were up/closed, and it happened to be in a position where my new Professional Products Harmonic Damper has all of its timing marks on top. I'm going to need an early Mustang timing pointer because I'm using a water pump with a left facing outlet which will block the timing marks on the left side. However, the harmonic damper that I have has early Mustang timing marks on it as well and just eyeballing it....it looks like these timing marks are exactly where they need to be with the engine currently at TDC. Also...I have a hunch that the keyway on the crankshaft points straight up at TDC and I know where the keyway is on my harmonic damper and after I got it close to TDC, the keyway is pointing straight up. I appreciate the help guys....yall are always willing to lend your know-how. Currently....it's just funding that's keeping me from buying the last few bits that I need to fire this badboy up. (still need an alternator, starter, fan and the cheap stuff likes plugs, belts and hoses) Hopefully I'll be able to do that in January and post a video of it coming to life.
you stated its an 88 302 . have you bought a special balancer ? or just an old balacer . long about 80 i think ford changed the way they balanced the engines and if you use the wrong balancer it will vibrate . also when bringing the engine to tdc if you have someone hold there thum over #1 sparkplug hole while rotating the engine it will blow air out under there thum when its on the right stroke . you can also use a comp. gauge and watch it grow the pressure .
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