James

What is the correct way heater hoses should be routed on a 69 Big Block with the expansion tank?
I'm looking in the AIM manual and it does not look super clear to me.
I also see in a number of parts catalogs the use of a "T" connector in some configurations.
To me it looks like the bottom outlet on the Heater core connects to the outlet on the intake manifold with 1 long 5/8 inch hose.
A 3/4 inch hose runs from the top outlet on the heater core to the connection on the expansion tank that faces towards the fire wall.
Then another 3/4 inch hose comes off the connection on the expansion tank that faces towards the front of the car and connects to the water pump.
Is this correct way?
:rolleyes:

marky mark

I'd have to look to be sure but that sounds correct. Also, one more hose connects to the inlet near the front of the expansion tank. This hose comes from the top of the radiator and becomes the outlet for water to flow from radiator to expansion tank.

You're on the right track.

:flag :chevy

James

Marky Mark, If you get a chance to take a look could you let me know?
Thanks.
:cheers:

marky mark

James, the hose that connects from the radiator is smaller in diameter than the other hoses. It connects to the outlet near the top of the expansion tank. Thought I'd be more specific on that one.

Just looked at my car and your description of hose routing is correct.

If you are having over-heating problems I recommend using either a 180 or even a 160 degree heavy duty thermostat (napa approx. $8).

Good Luck!

Regards, mark

James

Thanks Marky Mark for your help.
I hope not to have any over heating problems.
I purchased a Griffin Aluminum Performace radiator and a Dual 13 inch Spal fan and shrowd setup from Tom Dewitt at Dewitt's.
It looks real nice and with both fans together they can pull 2700 CFM of air through the radiator.

427_Roadster

Looking at the AIM, the top heater core hose(3/4") goes into the fitting on the bottom of the expansion tank, back out the fitting on the other side and into the water pump. The lower heater core hose(5/8") goes straight to the manifold. The fitting at the top of the expansion tank goes to the radiator. I can't confirm this on my car since I rerouted the hoses to bypass the heater core.(Going to replace the core on the next warm weekend.) But, looking at pictures of my engine, it looks like the previous owner had the hoses reversed from what the AIM described.
Hope this helps a little...
:cheers:
Tom

Wrencher

The previous posts are correct on the routing. The one thing I would add is that the cars with A/C had a hot water shut-off valve in the 5/8 hose running up to the manifold. It is mounted to the RH lower part of the heater case in front of the heater core pipe outlets. You can see it if you look in through the "gills" on the RH side.

Hans

James

Thanks everyone will wrap it up tonight.
On to the vacum lines.

Clink69

Does this matter if the large hoses are reversed on the heater core? Mine are.

marky mark

I would think it might have a negative affect as flow of water is interupted. But,if you've been driving it and she doesn't overheat, maybe it doesn't really matter?

Regards, Mark


[Modified by marky mark, 4:24 AM 3/1/2002]