Bleeder Screw on Coolant T

[joelittel]

Other than filling the cooling system what is that little bleeder screw above the temp sensor on the coolant T for?

Is it intended for bleeding out any trapped air from the system?

[redcars]

The Fiat manual tells you that is where you add coolant when you are getting the traped air out of the coolant system. It is what I use whenever I have drained the coolant system when I have work on my Spiders. Works like a charm for me.

[westy64]

could anybody show this bleeder on a picture, and maybe the whole part with this bleeder.
I am thinking of going to such a solution (bleeder on the T to ease the air bleeding).
whether I would drill a bleeder, or replace the existing part.
thanks

[RRoller123]

[azruss]

jean,
there are version of the coolant T that have a restrictor hole on the left end and some that are full open on the left end. Dont know why or what years. My 80FI is one with a restrictor hole.

[RRoller123]

I forget, but the restrictor goes to the t-stat side or radiator side??? I think I was T-stat side, and mine was rigged up with the sensor and bleeder screw caddywompus when I bought it, (bleeder bottom, sensor top (!?) although restrictor was correct. I think if you get it backwards the car will overheat pretty quickly.

[seabeelt]

Restricted side toward the thermostat definitely
R/

[RRoller123]

Yeah thanks that makes sense. So you can see in my earlier bottom picture that the sensor had been installed in the top and the bleeder screw in the bottom hole, which is backwards, although the restrictor was correctly oriented to the t-stat side. It is amazing what gets done by POs to these cars. I get surprised pretty regularly.

[westy64]

My 2 cents :

the above procedure states that the right upper hose is to be disconnected and filled manually to avoid air in the upper circuit.
right.

I would suggest the following mod to the procedure

0 - open the coolant T bleeder, and put the heater core "on".
1 - disconnect the lower hose from the T-stat.
2 - fill the radiator until this hose overflows.
3 - connect the hose to the T-stat.
4 - keep filling the radiator until it's full, then close the radiator.
5 - disconnect upper passenger hose from the coolant T and fill it until it is full, then connect it to the coolant T.
6- release the boiling tank from the firewall and lift it over the radiator level (hang it on the hood, for example).
this will push the liquid down into the whole circuit, and push air ahead to the way(s) out.
7 - add liquid into the the tank until you see the coolant T bleeder overflows ; now this part of the circuit is air-free.
8 - close the coolant T bleeder.
9 - open the upper bleeder (flush'n fill bleeder); air should get out through it, as coolant comes down from the tank into the engine circuit.
10 - keep on adding coolant into the tank until the flush'n fill bleeder overflows, then close the upper bleeder.
11 - adjust the liquid level in the tank (add or remove some) and fix it back in place on the firewall.

this allows you to remove all air from the circuit before starting the engine

just my 2 cents.