Snapping sound under load.

[Dick Steinkamp]

True dat, Dave. If the timing is advanced to the point of preignition (detonation) it will generate a lot of heat. I should have qualified my agreement .

[forever4]

Originally Posted by Dick Steinkamp

True dat, Dave. If the timing is advanced to the point of preignition (detonation) it will generate a lot of heat. I should have qualified my agreement .

Please explain

[Dick Steinkamp]

Originally Posted by forever4

Please explain

See point #3 here...

http://www.rootesparts.com/id201.htm

4th paragraph here...

http://www.automotiveu.com/SolvingOverheating.htm

the paragraph under Ignition Timing here...

http://www.speedwaymotors.com/the-to...ng-cures/28793

[Glen in Hillman MI]

Have you checked for carbon buildup in the combustion chamber yet?
Carbon buildup plus full or advanced timing plus engine under heavy load equals engine noise, especially just before you stall if you push it that far. Could this be what you're hearing?