fitting on side of block?

[longbedrick]

what is this fitting? there is a plug on the driver's side, and this fitting on the passenger side, just above the exhaust manifold

[longbedrick]

forgot to mention, it's a 1973 454 big block

[STOCKISH]

Looks like whats left of a coolant temp sensor.

[longbedrick]

whatever it is, it looks broken for sure

[bitchin85]

yea its your coolant temp sensor that got snapped off..

[CSGAS]

Have you put coolant in it this way (and does it run out the broken sensor)? My first thought was that someone tried to plug AIR passages in smog heads but that sensor looks like it broke when someone was trying to pull it to put another plug in that side; and that doesn't seem consistent with my thunk, AIR passages wouldn't have sensors...may have had vacuum switches though.

I also talked myself out of my second idea, 1973 seems too early for a knock sensor.

[bitchin85]

it wouldnt leak out.. theyre solid all the way through. the only thing wrong with this picture is that his temp guage dont work.. (unless its hooked up somewhere else)

[CSGAS]

OWAITAMINUT!!! I just pulled my TSC wiring today and should have thought of this right away.

Those retard systems (no, I'm not making fun of anyone, the systems kill the advance when installed) use a temp sensor in the head to work, and in small blocks it's at the front of the passenger head. I suppose on big blocks it would have to be the side of the passenger head, and it would be dry (no leaks even when running) instead of reading from coolant. They don't seem to show up in manuals either.

[longbedrick]

she hasn't run in over two years. I saved it from the DMV "amnesty program". I'm going to try and get her to turn over this week. I've been erradicating rodents and collecting parts since I got her. I have no idea if the gauges work

[CSGAS]

No, back to plan A...I'm too tired and distracted with a few family members in the hospital and I thought I'd get my head straight by visiting the board again...gimme a big Nelson "ha, ha..."

That is where the regular old coolant temp sensor is on big block heads...I gotta play with more big blocks again sometime soon I guess.

[spinem]

broken temp sender

[raws67]

Thats a temp sender passage. Keep in mind that there is no left head or right head so the threads for the temp sender will be on either side. One is plugged and the other will have the sensor. Early engines used a temp sender in the intake manifold but normally for your application the sender would go on the forward half of the drivers side causing the passenger side to have a plug. If it dont leak and you have a good temp sender on the drivers side head then dont mess with it. Just think of it this way, if you took the passenger head off and put it on the drivers side you would have a threaded boss to install your temp sensor. The gauge might work if they used a temp sender in the intake manifold. But either way that is the temp sender port for that year of engine. or its a place to install a plug because the sender is on the other side. Hope this clears it up for you.