Can anyone tell me what these 3 connections on the radiator are for, where they should go, and how I'd block them off if I didn't need to use some/all of them?
<from the bottom, going up>
1. electrical spade connector
Is this a temp sensor? I have a metal "spike"-type temp sensor for the fan relay on the other side of the radiator, so do I need anything here?

2. Hexagon edged pipe thread
Not sure what this is.

3. Standard small coolant hose.
Maybe heater hose? I currently have the heater core in/out connections to the water pump and manifold.

4. Small coolant hose.
Overflow, maybe?
Any help here?
Thanks!

 

The 1 right under the radiator cap, the shiny nipple is for over flow tank.
IDK the others.

 

Tranny cooling.

 

#1 - I think thats the coolant level sensor. Not many f-bodys got this.
#2 - Hexagon thing is a transmission cooler line connection. Should be another one down below the coolant level sensor.
#3 - Thats a coolant return fitting.
#4 - Thats a coolant overflow fitting for the overflow bottle.

 

I would be wholly surprised if that was a level sensor and not just another temp sensor. That is way too far down in the radiator to be an effective level sensor. That low and you'd be cooking things.

 

I thought it wouldnt be the low coolant sensor. I thought it was too low in the radiator too but I know they put the sensor in the radiator somewhere.

 

The top one is for the overflow to overflow tank,
the one under the overflow is for the heater hose,
the third one is the trans cooling line.

 

And the one under that is a coolant level switch found on some replacement radiators. Mine happens to be an ACDelco that has it...

 

Hmm...

So if I have the heater core in/out going to/from the water pump and intake, what should I be doing with the heater hose connection on the radiator, then?

Thanks!

 

You could just block it off with a rubber cap. But for a more leak proof connection, return the heater hose to this port in the rad, and put a steel plug in the water pump.

 

The replacement radiator that I installed in my 86 is set up similiar to yours. We blew the tops off of three rubber caps and lost all of the coolant, before deciding to tap inside of the hole with a pipe thread tap and install a brass plug in it. The rubber caps are not strong enough to withstand radiator pressures, and will fail at a bad time, leaving you stranded somewhere. The fitting on my radiator is thick and made of solid brass. I placed a little RTV sealer on the threads of the brass plug, and snugged it up enough to seal, but not tight enough to break off the fitting. Painted the plug with some black paint, and no one notices that it is there. It has been that way since 2006.

We had the same thing happen on a truck that I had an aftermarket intake manifold on it that came with an extra water outlet. The mechanic who installed it, used the rubber cap provided by the company who sold us the intake, capped it, and it blew the top of of the cap a week later. Same thing, except the coolant went into the ignition, and shorted it out. That was not a cheap repair.

The previous poster who mentioned routing the return heater hose to the radiator, and screwing a plug into the old heater return post on the water pump made a great suggestion. That would be my first choice.

Either way, I would stay away from rubber caps.

Charles

 

OK - cool. Thanks for the input.

So I think I'd like to reroute an existing cooling line and block off one of the others. In the attached picture, which one should I take out and reroute to the radiator, the manifold or the water pump?

Thanks!

 

Block off the water pump, that's the heatercore "return" line which is the same line that also goes to the radiator on the later model 3rd gen's that have the radiator mount. Those cars don't have a port on their water pump which is the only difference.

 

Ive had a rubber cap on my rad heater outlet for a year (GTA is not my dd) and it has held up fine; tighten it on with a hose clamp and from my experience you should be fine.
But i agree with the others on running your heater hose to the rad for a guaranteed no leak fix.

 

Ditto

A 1/2 plug with pipe threads should fit your waterpump housing where the heater return fitting is now.