Hello everyone. My first time working on a project on my own, just want to verify I’m ok to move forward putting it back together. She was sitting a long time. Started by swapping most of the fluids and hit a snag flushing the radiator. Hadn’t noticed any smoke prior to, motor felt strong in first and second (can’t give it much throttle in 3rd, need to look into that). Compression was 150-160 with no leak down. During the first prestone flush, she started running a little rough on a short drive around the neighborhood…heat maybe worked too good. Did a second flush and got much worse after it was up to temp. Smoked a decent amount and could tell at least two cylinders were worse watching smoke rings out of the tail pipe. I assume some stop leak was used. Oil was clean, no milky stuff and top of head looked good (outside of a valve seals that were blown apart or cracked). Valves must have been replaced, no damage where I found the tapped piston. Straight edged the block, didn’t see any issues. I’ll take the head to a shop for a once over and verify it’s good. Anything here to worry about or anything I should be aware of?

While I’m in this deep, I’ll get 30 years of gunk off and paint block, brackets, et all. Have all new rubber when she goes back together as well.


Old gasket, part number revealed felpro

Block before cleaning

Wd-40 and green scorchbrite

#5 tapped a valve at some point

 

As far as the symptoms go from when you were first testing with the coolant flush, the issue could be the Coolant Temperature Switch. Here are symptoms of a bad CTS and the smoke which was new to you is a symptom.

• Engine Overheating. ...
• Illuminated Check Engine Light. ...
• Black Smoke from Exhaust. ...
• Difficulty Starting the Car. ...
• Fluctuating Temperature Gauge. ...
• Rough Idling. ...
• Radiator Fan Problems. ...
• Transmission Shifting Problems.

Here are testing procedures to make sure the CTS is the culprit.

1. Connect the voltmeter’s positive lead to the sensor’s signal terminal and negative to the chassis ground.

1. Cold start the engine and check the readings. The reading should be between 3V – 4V, depending on the engine’s temperature.

1. Let the engine get warmed up to its operating temperature. The voltage reading should drop (for an NTC sensor) to 1.2V – 0.5V.

1. If the voltmeter reads 5V, it implies an open circuit. They’ll check:
   • Signal terminal connection
   • Sensor’s ground contact

1. If it reads 0V, this indicates a short circuit or no power supply to the sensor.
   • Check the connecting wires from the ECM to the sensor
   • Check the power supply and ground connection for the ECM

1. If the voltmeter still reads 0V, the ECM can be faulty.

If the voltmeter’s readings are beyond the range prescribed above for a cold and hot engine and there are no connection problems, you’ll have to get the sensor replaced.

 

Thank you for the reply sandymane. I suspected an issue with that unit, gauge wouldn’t go above 1/8-1/4. Replaced thermostat and made sure coolant was flowing through system, definitely running hotter than the gauge showed. Found the boot on the wire was partially broken for the CTS. I’ll replace the wire and unit to be safe.

Attached a video of the smoke prior to the tear down, only white smoke. Motor seemed strong enough that I don’t need to rebuild it. Being that it was running well in first and second gears, the dented piston I assume isn’t an issue. My thought on 3rd bogging down is the EGR may be stuck open or a vacuum issue. I’ll test everything as it goes back together.