I’m having an issue with a new swap. Finally got it running correctly, took it for a drive and it started overheating. Got it back home, tested thermostat, it was bad, replaced it. Still overheating.

fan wasn’t turning on. Wired it so it’s constantly running.

Now it stays operating temp while driving for a couple minutes then randomly goes redline hot within 10 seconds. When I shut the car off it isn’t steaming or anything. I can actually rest my hand on the valve cover. Doesn’t seem over heated?

when I just have the key on it’ll be at more of a normal operating temp. But as soon as I actually start it it goes back to red. When key is off it going all the way down to cold obviously.

im mainly confused as I don’t see how it could be overheating. Wondering what steps I should take for troubleshooting

 

Probably have to get the air bubbles out of your cooling system. Some people call it burping it.

 

I ran it for like 10-15 mins with the cap off

 

Just now burped it properly. Said it was overheating within 100 yards of driving it from cold start

 

Verify temp with an infrared thermometer.

 

im pretty sure it’s the coolant temperature sensor. Gonna swap it tomorrow

 

Replaced the sending sensor and the coolant temperature sensor. Issue is not solved. Pegging red but is not hot. Not even to operating temperature, I’m baffled as I have tried 2 different clusters and both do the same thing

 

What head gasket did you use for the mini-me? Isn’t there one type of gasket for D16Y5, D16Y8, and D16Z6, and then there is another kind for D16A and D15B?

 

Zc block y8 head not sure what gasket i got the swap complete

 

Unplug the single wire from the coolant temp gauge sending unit on the distributor side of the head. Does this cause the temp gauge to read cold or does it still appear to function... and maybe even rise to full hot ? If the gauge rises, then there is some type of grounding occurring on this wire causing improper readings. If not, replace that sending unit and re-test.