Thermostat and Gear Oil

[tercle]

Why does the lower radiator hose connect to the thermostat housing on a 3A engine?
Isn't the thermostat usually at the top hose of a vertical radiator?
How does it even work?

Does the gearbox and the differential have separate oil supplies, or does it all get mixed together?

[ARCHINSTL]

I can't answer for the t-stat questions.
The transmission and differential share oil through common passages. If changing, BE SURE to loosen the filler plugs BEFORE the drain plugs - and definitely read the several threads concerning the softness of the drain plugs (and modified tools to open them) as well as the entire filling procedure.
Tom M.

[takza]

The cooling system is sort of bassackwards...but it works. Wait till you deal with the rad fan switch....default is ON.

[Petros]

cooling systems have become more complicated since the earlier systems where the t-stat was on the outlet side. The lower radiator hose actually connects to plenum or manifold of sorts that controls both temp and where coolant flow is directed. When the temp is cold right at start up the t-stat forces all the coolant to circulate through the heater core only, giving you heat in the passenger compartment first. When the coolant temp warms up the flow is slowly sifted from the heater to to the radiator, but always allowing the warmest coolant through the heater first. when fully warmed up to operating temp the t-stat than regulates and maintains coolant temp in the engine, never being fully open unless you have exceeded the cooling capacity of the radiator, which should never happen if everything is functioning properly. So the t-stat and all the associated plumping is a true thermostat not just an open/close valve.