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Can't find my marks!

694 Views 5 Replies 6 Participants Last post by  RTM
After installing a new MSD distributor and losing the rotor position prior to removal (doofus!), I need to manually find the TDC position but can't because I can't find my timing marks anywhere on my 289. Also, how do you crank the engine without firing the ignition? I heard it be done with a rachet? Any advice?.....THANKS
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To crank the engine without firing it, just pull off the primary coil wire.

Take some carburator cleaner or brake cleaner and wipe down the outer ring of the harmonic dampner with it. You may have to scrub lightly with some 00 steel wool to help remove the gunk that's concealing the timing marks. They are there ... you just have to uncover them.
You can turn your engine over with ratchet by putting a socket on your harmonic balancer bolt (you know, at the crankshaft pulley). IIRC that bolt is 13/16", but don't quote me on's been a year since I've done it. I use a 1/2" ratchet, because it takes a little heft to turn it. If you want to make it easier, take your spark plugs out so you won't have to work against engine compression.

Personally I verifyed TDC with my heads off, but hopefully someone can tell you a trick to use. Seems like you can do something with the the air pressure at #1 spark plug hole?

Good Luck!

After you clean any gunk off of the harmonic balancer, take some white chalk and scuff it up with that. Then wipe the chalk dust off a little with your finger. Some will stay behind inthe crevices where the marks are if they aren't totally worn away. THis worked on mine, they were almost invisible before!
I keep a bottle of white model paint in my tool box to mark the marks. Clean it up as already stated. Mark the marks.
I'd remove the plugs, crank the engine over with a ratchet, keeping my finger over the #1 hole. when you feel the compression stroke, verify the marks coming together and you'll be getting clost to TDC. A small wooden dowl can be used to "feel" when it tops out. Make it a long one so it does not get lost in the cylinder. This is not pinpoint accurate, but will get you started.
To get the TDC again I remove the valve cover and I also remove the #1 spark plug. With that done turn the motor over with a rachet, 15/16. While turning the motor over watch for the #1 cyl. intake valve to open and then close. After the intake vale closes feel for the piston to come up to the top. I use a screw driver to do this. Do not plug the hole with your finger. You will feel the piston pause at the top. If it starts to go down then reverse the rotation and try again. Once you feel you have the piston at TDC then drop the distributor in pointing towards the #1 on the cap.
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