TDC Question

[Swoboda]

I'm doing my first valve adjustment.

I've turned the crank to align TDC and the notch on the distributor.

Question: things look most aligned -- the TDC and the notch-- when the "second" mark on the pulley is aligned with the mark on the case. When the "first" mark is aligned the distributor notch appears "off". Could this be right--that the second notch is true TDC?

Thanks.

LS

[rattlsnak]

the first mark is at 5 degrees..

[boyt911sc]

Originally Posted by Swoboda

I'm doing my first valve adjustment.

I've turned the crank to align TDC and the notch on the distributor.

Question: things look most aligned -- the TDC and the notch-- when the "second" mark on the pulley is aligned with the mark on the case. When the "first" mark is aligned the distributor notch appears "off". Could this be right--that the second notch is true TDC?

Thanks.

LS

LS,

Top dead center is the 2nd. mark on the crank pulley (CW rotation). The position of the distributor rotor is to distinquish between compression and expansion (exhaust). When you are doing a valve adjustment for cylinder #1:
a). Crank shaft pulley @ Z1.
b). Distributor rotor pointing to marker on distributor housing or to #1 plug wire.
c). Follow the 1-6-2-4-3-5 sequence every 120°. After cylinder #5, you are back to cylinder #1 to check your gap.

It is imperative that you start @ cylinder #1 @ compression (ignition rotor pointing to marker). Double check your gap measurement multiple times until you are satisfied with your valve adjustments.

Tony

[T77911S]

the rotor and TDC will not align due to the advance setting of the dist.
just line up TDC with the rotor CLOSE to the mark. its not that critical. you just want to make sure you have the correct stroke for TDC.

[Swoboda]

Originally Posted by boyt911sc

LS,

Top dead center is the 2nd. mark on the crank pulley (CW rotation).

Not to sound dense, but when the two marks are at the top of the pulley, the "left" Mark is TDC?

Thanks.

[boyt911sc]

Originally Posted by Swoboda

Not to sound dense, but when the two marks are at the top of the pulley, the "left" Mark is TDC?

Thanks.

LS,

Yes. Take a look at the picture below. The two (2) marks on top of the crankshaft pulley are:
LEFT........TDC or Z1
RIGHT......Ignition timing mark @ 5°



Do you have similar markers on your pulley? Got a Bentley Shop Manual? You seem too confused about this basic information for someone doing a valve adjustment. Have you done the ignition timing before? Keep us posted. Thanks.

Tony

[DRACO A5OG]

Just go oil school and stick a wooden in the spark plug whole to confirm TDC.

Plus like everyone stated here 2nd mark is TDC or Z, Dizzy should face #1 plug wire.

Here is my Clewet Pulley Z is TDC or 2nd mark

[Omegaman]

Stick a plug in #1 only, this will tell you if you are on the compression stroke as it will be difficult to turn as it approaches TDC #1...you can do the same for the other cylinders.