85 v6 no a/c heater core hoses

[wallace]

I have an 85 notch I'm putting a 3.8 v6 in it. Car was originally a 2.3 with no A/C. There looks to be two different size hoses for the heater core 5/8" and 3/4". Which way do the coolant line go from the engine? I have a place for fittings on the water pump and one right behind the t-stat. Is it 3/4" from the water pump and 5/8" to the manifold by the t-stat? I tried to search and found some posts but nothing about this. Any help would be greatly appreciated.

[bob85gt]

i do not know about the 3.8 but the 5.0 does have two different size hoses. the larger hose goes from the water pump to the large size on the heater core . and the smaller size is the return. becareful though , the reason it is not hooked up may be the heater core is leaking. the fact that yours is a non ac car should mean that to get at the heater core is easy. (about $30 if i remember) there is suppose to be a lid that is removed and pull the heater core out. (removeing the heater on ac cars is a pain). ford later put a restriction plug on the 3/4 side. you can do the same buy taking a copper tubbing end plug and drill a 1/4 hole in it and use this to restrict the water flow.(thats what i did).

[wallace]

Hey thanks. The car ran and drove when I got it I don't think the heater core leaked. I have the heater assembly out of the car and if its just 30 bucks I'll spring for a new core. Was the reason they used two different size lines to slow the flow down out of the core? I was thinking using the 5/8" on the outlet was sort of a restrictor anyways?

[bob85gt]

if you look at the heater core (at least on the one i put in) the 3/4 is reduced to 5/8 almost right away. why they did this ??? there is almost always a story behind it, but i do not know why. good luck with the car.

[biscwgn]

I have a 86 Notch 3.8 Liter bone stock if you need pics for reference let me know