I would like to install a new original harmonic damper on my 3.8 e type. The original setup has the timing markers in the very bottom at top dead center and the timing indicator on the oil pan. I have a marker as well on the side of the timing cover to be able to time from the top. I thought Could just adjust where I install the balancer to line up with the top index but the balancer lines up with a key on the crank piece which allows install only in the original location. I will have to make my own timing marks on the balancer to use from the top. Anyone know Thebes way to do this? A file?
Line up the below marks one last time after checking accuracy on the front cylinder with the double stop method. Then just mark the damper rim where the upper pointer sits. Then meaure or calculate the circumference and divide by 360 to get the distance per degree for your static timing set point and a scale up to max advance for strobing.
I’d verify it as Peter suggests, especially if it’s rebuilt. Ideally the marks would have been perfectly preserved in their original orientation but who knows? The sump pointer has a bit of side to side adjustability so after setting the piston physically to TDC, verify the pointer is zeroed.
Assuming you always set it to the standard advance advance for the 3.8, then you could simply set it to that using the bottom register, then make a new mark up top next to your upper pointer. I’d lay two pieces of tape with a tiny gap and paint a little line with nail polish.
If you want all the degree marks then you’ll need something more advanced. You could also make a similar mark on the flywheel edge to line up with the arrow on the bellhousing.
The balancer is keyed to the crank so you can’t adjust where it points.
Set the engine to TDC, check the existing marks on the bottom then just use a Dremel or a file to make marks to line up with your other pointer. I use a white paint pen to highlight the new marks.
The 3.8 bellhousing has an inspection hole on the left side, just behind the rear header pipe. The flywheel has a TDC mark there. Using that, and a dial-back timing light, you can set timing from the top with the stock damper. To re-locate the timing marks on the damper, you’d have to either have it taken apart and put back together with the outer ring rotated by a precise amount, or cut a new keyway, then have it re-balanced. Seems like a lot of time, money, and effort for so little gain.
thanks everyone-I used the #1 (rear most cylinder/firewall) and set it to tdc with a tool in spark plug hole and verified it with then installed fluid damper and it was right on. Marked crank flange to make sure it did not move when removing old damper-also had car in gear and park brake on.
Think I will do the white nail polish/file thing-great idea. use fine brush to mark out at least every 5 degrees as also mentioned. Also thanks on the flywheel mark-I have an aluminum one from Fidanza so hope it is so marked.
Peter-can you explain the “double stop method”?