timing question

[ben jones]

I made a Novice mistake and blew the pre amp in my distributor. In the process of resetting the timing on my motor (1981 75hp chrysler) I found it is to be set at 32 degrees BTDC. The question I have is when I initially set it up should I have it set at TDC when its starting or should I have it set at 32 degrees BTDC. Im thinking it should be at TDC when cranking and when I throttle up the advancing distributor should make it fire at the 32 degrees BTDC. Whats confusing me is the seloc book says clockwise when my motor spins counter clockwise. So when im looking at the front of the motor my 32 degree mark is to the left of TDC this means that I am actually setting the advance for the second piston in the sequence Is this right? This is the first time ive done this im mechanically inclined but this is confusing me a little. What I really need to know is should the BTDC mark be to the left of the TDC mark looking at the front or carbs on the motor. I need to know If I am setting the spark advance for the top piston or the second piston in the sequence. I will make sence to me once I know that.

 

[Frank Acampora]

Re: timing question

Looking down at the flywheel, your engine spins clockwise, like every Chrysler and Force.

To set timing you first ensure that top dead center is really top dead center and set the block pointer to match TDC line on the flywheel. Look at the distributor pulley and be certain it has the curved line matching the flywheel curve with the straight line pointing directly at the flywheel.

Next, with the top plug out and no gas in the engine, you put the control handle in wide open throttle in forward gear.

Now remove the top sparkplug and ground it where you can see it. Turn on the ignition switch and SLOWLY turn the flywheel clockwise by hand (To be safe, remove and ground the other plugs too). Note where the plug fires and adjust the timing link at the distributor until it fires at 32 degrees BTDC, that is the 32 degree mark is at the block pointer. If you want to be safer, set it at 30. Chrysler did change the timing spec to 30 in the early '80s. That's it!

Timing at idle is dependent upon the idle stop screw setting and can not be adjusted. It can vary from -2 degrees to +2. It is not a major concern.

Firing order is 1, 2, 3, with top cylinder as #1. The distributor belt MUST NOT be adjusted too tight or the engine will have trouble shifting in and out of gear. Too loose and timing will wander. The belt is at the correct tension when an .010 steel feeler gauge pointed like a finger in the middle of the belt deflects the belt about 3/16 inch before bending.