So let me go at the mechanical advance issue in a different way. Its not a question of whether its advancing, its a question of whether its advancing properly. If the springs are weak or one is broken, the advance will come in too soon, if too stiff or gunked up, the advance comes in too late. Not too long ago I had a new old stock 2403 distributor on my Sun distributor machine. The advance was coming in way late. Took it apart, all gummed up. Good cleaning and fresh lubrication, back in specification. The mechanical advance has to not only be working, but working properly.
You are spit balling a little here. You apparently repaired the original vacuum advance but you don't know the specification for the advance. The mechanical advance is advancing but you don't know the curve and do not have the tools to sort out how fast, or slow the advance is coming in, or to what extent in terms of total distributor degrees. Couple that with I am not 100% sure that the flywheel bb is accurately positioned to indicate tdc at the bellhousing pointer. Is the flywheel original to the engine? is it original to the bellhousing?
I am not trying to be critical here but hanging parts, pouring concoctions into the fuel, is not the best way to sort this out. I think you need to go at this a little more methodically. You need a base line to get started and that means you have to first get a handle on true tdc. Not guessing, speculating, but determining true tdc. Everything relative to the ignition system is dependent on knowing that specification. From there you can confirm that the octane selector plate is installed at the 0 hash mark at tdc, confirm that the rotor is pointed at the No.1 plug wire tower on your cap. Once you know tdc, you can start methodically knocking off the rest of the low hanging fruit.
You should take the top of the distributor apart, inspect, clean and lubricate the mechanical advance. Put it back together, adjust the points, get it started, hook a tach and dwell meter up (don't have one? then you need to go get one. Indispensable for point ignitions. Used units are pretty cheap on ebay) and confirm that the dwell is within specification. If not, readjust the points until it is. Now set and confirm your timing with a timing light. Same deal. You don't need a fancy light, plenty of used working units on ebay for not a lot of $$. Now you can move on to adjustments to the carb, set the idle speed, valve adjustments, etc. But it all starts with an accurate tdc, in my opinion anyhow.
Pinging is almost always related to ignition and advance issues. If you have checked and double checked the ignition system, then you know the issue lies deeper, cracked piston, leaking water in combustion chamber, something other then ignition. .
Last edited by Dragsix; 02/02/2024 5:09 PM.
