Topic: heater hose routing

[cool67]

On a 69 mustang (probably all models) Which the heater hoses goes to the upper most firewall heater hose hole and which to the bottom of the two vertical holes in the firewall.

[Brian Conway]

     On my 69/428 the waterpump hose goes to the upper/top opening.  Brian

[J_Speegle]

Believe there are pictures of the routing (both AC and non AC as well as different engine sizes) in the Assembly manuals

[priceless]

Now on my 69 351W in my mach1, the water pump heater hose goes to the bottom outlet. The top outlet come straight out and connects to the heat activated choke assembly attached to the carb. Then straight to the intake connection. That would only make sense since it comes straight to the carb choke assembly.

And as I remember, that the way its always been on my 351W....Hope this helps.

[fast66]

IMHO it is in fact the opposite - The heater inlet hose is routed from the intake manifold fitting to the bottom heater core tube. The heater outlet hose is routed from the top heater core tube to the water pump inlet via the choke retainer.
In fact my friend, who has a mostly untouched 1969 GT coupe with 351W, and I have discussed this several times and it certainly is connected like that on his engine. This goes for small blocks - don't know about big block engines.
jm2c
Claes

[priceless]

Should I reverse my hoses to where the upper heater hose attaches to the water pump and the lower hose attaches to the intake, or does it really matter?

[jwc66k]

Should I reverse my hoses to where the upper heater hose attaches to the water pump and the lower hose attaches to the intake, or does it really matter?

Swap them. Heater water going in the bottom then out the top of the core forces any air bubbles out of the core.
Jim