atomic-4 tune up

[tracy]

I'm tuning up my 1979 atomic-4 on my Catalina 30 (new points, cap, rotor, plugs and wires) and I was wondering if I have to re-time it.If so, can I do it without taking off the flywheel cover? is the timing mark (pin) on the cam visible where you hand crank the engine. If it is on the cam, should I cut or drill an access under the dining seat since there seems to be only a couple or inches of room? THANKS

 

[Garry @ S/V TASHTEGO]

Timing the A-4

There should be a timing mark on the flywheel cover. The timing is done using the pin in the end of the crank where the hand crank connects. When it is straight up and down the no. 1 piston crank is at TDC (or BDC). To check, pull the plugs then put a finger over the plug hole for the #1 cylinder (closest to the flywheel) and turn the engine over by hand. When you feel air pushing out under your finger the engine is coming up on TDC on the power stroke. On my old A-4 there was a notch in the sheetmetal flywheel cover in the top of the opening through which the crankshaft projected. Some A-4s have a cast flywheel cover which I have never seen and I don't know where the timing mark is but it is probably somewhere on the flywheel cover near the end of the crankshaft where the cross pin is. Whenever you replace the points you must retime. Always set the gap first then the timing as changing the gap changes the timing. If you set the gap with a feeler gage then check the dwell when the engine is running remember that changing the gap/dwell will move the timing. My old Bugeye A-H Sprite had a Lucas distributor which had a link from the base plate to a threaded link outside the distributor body. You could move the timing back and forth about ten degrees by turning a knurled nut on the threaded link. This may very well be the only good thing Jacob Lucas ever invented. He is known by those who have owned English sports cars as Jacob Lucas - Prince of Darkness. I wonder if one of those Lucas distributors would fit an A-4.