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Discussion Starter · #1 ·
Hi, I posted this in an old thread, but maybe will get more looks here.

I need to find TDC on No. 1 to install the distributor. I can't rely on the marks on the balancer because this engine uses a balancer off a different engine, so the mark won't line up.

My understanding is that the rotor passes the No. 1 position on the cap TWICE per engine rotation, and that only ONE of those times is the compression and ignition.

I've tried the finger in the hole trick, and I get strong air pushing out EACH time the rotor passes No. 1.

I took the valve cover off and watched the valve action, and used the straw in the cylinder trick, and sure enough, each time the rotor passes No 1, the same thing happens: Both valves close, the cylinder comes up to top, then the exhaust valve opens.

When both valves are closed, I can rotate the pushrods with my fingers, so the adjustment seems right. Plus, this car was running prior to the distributor being taken out and the timing lost.

Any help would be greatly appreciated!
 

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Discussion Starter · #2 ·
Also, one thing that would help me quite a bit:

When No. 1 is at TDC compression, what is the position of some of the OTHER valves? I can use one/some of those positions to confirm I am at TDC compression on No. 1.

Thanks!
 

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Don't watch the rotor, watch the intake rocker arm....when it opens, then when the piston reaches TDC, thats when #1 should fire.
 

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I found this info. Maybe it will help. I'm assuming you have the valve covers off already.

pull #1 spark plug, cut a piece of coathangar and stick it in the hole. remove valve cover, turn engine over, while watching the valves for #1. as the piston pushes the coathangar up AFTER the intake valve opens you will know you are on #1 compression stroke...then you can use your timing pointer and '0' should be top dead center (as long as the outer ring of the balancer hasnt slipped). If you find top dead center while the exhaust valve is closing, then you are at the exhaust stroke and one complete revolution of the crankshaft to tdc again will be compression stroke, where you can drop in your dist. again for #1

This came from another site that I Googled. If you need the link, let me know. But this was basicly the only info detailing the procedure.
 

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Porschev said:
My understanding is that the rotor passes the No. 1 position on the cap TWICE per engine rotation, and that only ONE of those times is the compression and ignition.

I've tried the finger in the hole trick, and I get strong air pushing out EACH time the rotor passes No. 1.
.......
If you are speaking of the post about a sbc then you are wrong. The rotor makes one revolution to every two revolutions of the crank. You should feel air each time the rotor comes up on #1.
 

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poncho62 said:
Don't watch the rotor, watch the intake rocker arm....when it opens, then when the piston reaches TDC, thats when #1 should fire.
Poncho...
Shouldn't that read "after the intake valve CLOSES" (at BDC) and the piston is on it way back up to TDC (Compression stroke)?
HowStuffWorks
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Poschev...
Both valve will be closed on the compression stroke.

When you are on the compression stroke, it should be impossible to hold your thumb over the spark-plug hole. If not ... it's time for a compression test and (if verified to be very low) ring and valve job.
 

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Most accurate way is to use a tdc stop that screws into the # 1 spark plug hole. Once you screw in the stop slowly rotate (by hand) the engine until the piston comes up against the stop. mark the balancer. then rotate the engine in the opposite direction until it again hits the stops. mark the balance. Halfway between the two mark is tdc. Even if your balancer had slipped you can use the new mark as your "zero"
 

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GCD1962 said the best way to find TDC and mark your balancer. Ponch62 got you to findin' TDC on compression. They are both right. Look no more and put 62 in your next lottery number...

Have fun,Smokey
 

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Have a friend stick his pinky way into #1 cylinder and bump it over until he screams. Get a new friend to grab the balancer and pulley to turn the crank so the timing marks line up. Get friend #3 to pull the dizzy cap off and see where the rotor is pointing. If it's not pointing to # 1 on the cap, get friend #4 to drop the dizzy in so it is.

Buy friend # 1 some beer.

tom
 

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It would help if we knew what engine you are working on. If it is a small block chevy. #1 piston will be at the top of the stroke, both the intake and exhaust valve will be loose and the intake and exhaust valve on #6 cylinder will be open.
Take the plug out and look in the hole for the piston or use the straw. With no marks on the balancer how are you going to set the timing? Might use a vac gauge.
 
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