engine timing

[a guy]

Is there an easy way to find TDC required for timing engine. Spent an hour yesterday with no success. Thanks for your help.

[RonC]

Are you using the timing pin?

http://www.abarnyard.com/workshop/timing.htm

[Patrick L.]

As Ron mentioned, you use the timing pin thats screwed into the timing cover. Reverse it and it should fit into a dimple drilled in the cam gear. If the dimple is too small then a small phillips screw driver may work. Some folks grind a point on the timing pin or use a flashlight and small mirror.

[a guy]

Yes. Using timing pin. Will try again. Thanks

[Tom Wesenberg]

Having the plugs out will help, but just slowly pull up on the crank until you feel the timing pin drop into the dimple in the cam gear. At this point the rotor should be in this exact position. Once set, the timing shouldn't have to be messed with again unless the distributor cam has been loosened or removed for some reason.

I think a lot of timing problems arise from people wanting to readjust it when it isn't needed. Timing won't change on it's own, and won't change because a car hasn't been run for 10 years. The points cam can wear and this will make the points gap smaller and retard the timing, but when you readjust the points to .020" your timing will be right where it was set to years earlier. Keep a little lube on the cam and the points rubbing block will have very little wear.

[40 Deluxe]

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Don't forget that you're just setting the base, or initial timing to prevent kickback when starting, especially if hand cranking. You need the spark to occur at TDC or slightly after, never before top dead center. Once the engine starts and you move the spark lever, you are no longer at that initial setting. It's rather amusing how some folks get all OCD over setting the initial timing down to half a gnat's eyelash, then pull the spark lever "down 2/3 of the way and leave it there" or some other spot that they just picked out of the air without understanding why. They don't seem to realize that all their fussiness just went out the window!

[BILL WILLIAMSON]

On finding TDC: I once had a WHISTLE, that popped onto the compression tester adaptor, it whistled when coming up on compression, BUT, changed pitch when you went past TDC!
Anyone know where I could buy one? P.M. me, PLEASE.
Bill W.

[bunnyc]

On my car, I have found it very difficult to find the dimple with the timing pin. I remove #1 spark plug and watch the piston. I find it the most accurate way for me to find TDC.

[29spcoupe]

Some timing gears have a very small dimple. Use a prick punch to find the dimple and then set the distributor cam.

[Brentwood Bob]

Some will use a flash light and a mirror to verify that they have the dimple.
Bob

[James Rogers]

If you look into the #1 spark plug hole with a flashlight, you can see the top of the piston when it is full up. Just make sure both valves are down when the piston is full up and you will be done.

[Brianfrench65]

I have used a stubby Phillips screwdriver, and that was the best for me. I could even do that without a helper. I could not get it right with the timing pin.

[1crosscut]

Sometimes it helps to find the dimple by removing the plugs, pushing the timing pin in against the gear and then turning the engine over with the crank handle fairly rapidly. You will feel the dimple bump by the pin several times and get a feel for where the crank handle is relative to the dimple location. After that you can slow down and turn it slowly to make the pin drop into the dimple.

[BILL WILLIAMSON]

Remember NOT to use the knotch in the cam as an indicator for # 1. It is 180 degrees from the BUSINESS end of the rotor. As a starting point, point the BUSINESS END of the rotor toward the R/F HEADLIGHT.
Ed did his 180 degrees off, blew off the Kzhaust pipe, DESTROYED the muffler & blew big chunks of stuff into his neighbors' garage, across the street!!!
Bill W.

[aermotor]

I'm confused. I thought the cam gear on 4 cycle engines was 2
X the crankshaft gear, so how can you get 180 out?

[Fullraceflathead]

Flash light and mirror is how I do mine. It's so easy to partially pass the pin with a shallow dimple.

[Willie Krash]

I agree with Tom. I don't mess with it much. In his photo you see where the rotor should be.
I turn it over by hand and as it approaches the #1 one terminal as Tom's photo shows I stop. Insert the pin and turn it a dog's hair more, very slowly. You will feel it. Be slow, after it goes over TDC it will get by you.

[Patrick L.]

Originally Posted by aermotor

I'm confused. I thought the cam gear on 4 cycle engines was 2
X the crankshaft gear, so how can you get 180 out?

The size of the cam gear doesn't have anything with getting 180º out. But, with an 'A' once the cam gear dimple is where it should be [ across from the timing pin hole] it would be very hard to get the timing 180 out. I won't say it would be impossible because people are just about capable of anything. On some other engines it is easier to get the timing 180 out by setting it while the engine is on TDC on exhaust stroke.

[marc hildebrant]

Originally Posted by aermotor

I'm confused. I thought the cam gear on 4 cycle engines was 2
X the crankshaft gear, so how can you get 180 out?

The comment about the 180 degrees referred to the distributor cam. This is the part that the distributor rotor fits into.

Marc

[aermotor]

Meant 2X diameter