Sudden overheating

[steve1]

I have a 1980 spider and just started having overheating issues - I have driven the car occasionally thru the winter and did not have any issues with the car running hot. I have not done any work on the cooling system. The engine timing was adjusted by a mechanic to get the emissions to pass. The past 2 days the temp gauge gets close to red - I had to pull over and wait for the car to cool down. I verified the fan comes on when shorting the wires and the fan did come on the first day the car ran hot when I pulled into the drive and turned off the car. I tried to burp the radiator (took about 20 minutes to get close to 190 degrees) and got a few small bubbles if I bounced the front end but the antifreeze kept overflowing the radiator. Does this sound like a air block or something else?

[Odoyle]

Could be the ignition is too far advanced, causing pinging. Guy Croft talks about this being a common causes of head gasket failure (specifically on newly rebuilt engines). You can buy a timing light from harbor freight and check to see if the distributor is at 10°.

[courtenay]

Could be the temperature sensor that pegs the needle is faulty. There are two sensors in the centre section of the block (between the spark plugs). The one nearest the front of the block pegs the needle the one nearest the firewall measures the temperature of the engine coolant. Disconnect the front one and go for a drive and see what the temperature gauge does.

[Nut124]

If it started to happen right after your mechanic adjusted timing, then I would suspect the timing is off and causing the heat.