motown 71

In the never ending fight against heat....
Does the shut off go between the intake and heater core or the water pump and expansion tank....
Thanks !

Wrecked82

I have them on both. Open in winter, closed first breath of warm air. Both make the difference. Otherwise, you will get a backflow heating through one or the other.

motown 71

Thanks Larry, Did you put the "lower" hose tween the pump and tank or tween the tank and heater core ?

Wrecked82

Don't know how the 71 is constructed. But on my 82 I have one on each hose connected to the water pump. Inlet and outlet.

motown 71

Thanks Larry.
71 plumbing is from intake manifold straight to heater core.
from water pump into expansion tank then to heater core.
I guess I'll go both with the lower tween the exp. tank and heater core.
Thanks again ! :flag

RMS73

I believe the water circulation route is from the intake manifold to the heater core and then back to the water pump, or at least it appears that way on my 1973. I would put the valve in the hose carrying the hottest water - the line from the intake to the heater core. Thats what I did. When I got the car both lines had manual valves. I would prefer to allow the heater to be able to "breathe". Without the valve in the return line I have notice no heat-up of the heater core.
Roger

motown 71

Sounds good.
Thanks for you help !
:flag

trw

Are both sides the same size?

What size manual valve am I looking to buy?

Summer is coming.

Thanks

Terry

RMS73

On my 73 the supply hose, from the intake manifold, is 5/8" and the return hose, to the water pump, is 3/4".
Roger

cardo0

:nono: That expansion tank would probally bust open with hot water once the car heated up. Heater core has 2 hoses: one goes to intake manifold and another goes to water pump.
Now for a shut-off valve a nice hardware store (Home Depot) ball valve will do the job. Its just that until the thermostat opens the water pump has no where to flow/circulate water. This would normaly circulate through htr core. So until the block water is hot enough (and T-stat opens) the water pump mostly cavitates with just a small amount of internal leakby/flow - not real good for pump. Easy to use 2 more valves for a manifold on the heater hoses. Two valves stop flow in & out of htr core and one valve open to allow bypass hose/flow to block. :thumbs:

kaiserbud

Its a little late tonight :crazy: - can you draw a schematic and post it? :cheers:

cardo0

Are u asking me (cardo0) for a schematic kaiserbud ? If u are my repley is no I'm not set-up here to draw graphics or even post pix.
But come-on kaiserbud your a piping designer and you need help with a by-pass hose? :troll
Use your noggen here and look there is only two heater hoses. Just splice into both and install a valve on one side/hose. Next use 2 piping Tees (I'm sure u know what this is) and install one each hose (yes, u can splice that hose again with that first valve or just run copper tubing off the end into a Tee). Secound valve goes between hoses/Tees for bypass control and yes you need to use a reducer somewhere here to mate the different size hoses but then again I'm sure you can handle this. :p:
Now I have to agree with RMS73 and the heater core needs to breath/expand/contract and only two valve should be used here. I don't recommend isolating the htr core (and should modify my first post calling for 3 valves).
So u need to exercise ur noggin again and think should u valve on the intake connected hose or should u valve on the water pump hose. One out of 2 here says u'll get it right. :troll

kaiserbud

agressive aren't we.
...enjoyed the discussion. :rolleyes:

cardo0

I'm sorry I Tee'd you off. But I am jealous of that beautiful BB of yours i see from ur profile. And a convertible too. :eek: I really think a great car like that belongs in So. Cal..
But any black car in Texas would be hot and a htr core bypass should help. Good luck. :D

Oopps. Ur pix just has the T-tops off. But hey, nice side pipes and I still want it. :)


[Modified by cardo0, 12:15 PM 3/7/2004]

RMS73

How about these:

and

Roger


[Modified by RMS73, 9:29 PM 3/7/2004]


[Modified by RMS73, 9:30 PM 3/7/2004]

kaiserbud

Thanks Roger :cheers: :cheers: :cheers: :thumbs: