Topic: Expansion tank question
in Forum: C3 Cooling and Heating Systems
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Lifetime MemberHot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
I just want to make sure I am doing this right.
I think the expansion tank goes between the water pump and the heater core on the 3/4" line.Then the intake connects to the lower (5/8") heater core connector.
then here is the tough question. if I want to shut off the heater core should I use a bypass valve rather than a shutoff valve? wouldnt I need to place it between the heater core and the expansion tank?
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Frederick, MD - USA
Joined: 9/8/2003
Posts: 3398
Vette(s): 1969 convertible L71 427/435 4-speed black interior
I don't know if we're talking about the same thing...to me the expansion tank is for the radiator, not between the water pump and the heater core.
|UPDATED|2/3/2012 7:43:41 AM (AZT)|/UPDATED|
If you want to shut off the heater core, all you really need to do is take the heater hose and run it from the inlet to the outlet on the water pump. You can use a 3/4" to 5/8" adapter for that. It removes the heater core and valve out of the system altogether. I'm not sure if that's what you want to do, though.
|UPDATED|2/3/2012 7:43:41 AM (AZT)|/UPDATED|
Lifetime MemberHot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
the expansion tank is part of the cooling system. is is connedted via hose in between either the heater core and intake or heater core and water pump.
i know i can just disconnect a host and bypass it. but there is not alot of room and id rather not have to fight the hoses of the heater core every year to do it.
Lifetime MemberHot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
I plan to leave it in. First and foremost i just need to verify that it goes on the 3/4 side
|UPDATED|2/3/2012 10:10:23 PM (AZT)|/UPDATED|
can someone who has a car with expansion tank intact tell me if it is in between the waterpump and core or intake and core?
|UPDATED|2/3/2012 10:10:23 PM (AZT)|/UPDATED|
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On this tank, the two lower fittings would be tied into
one of the heater hoses. The upper fitting on the tank close to the neck would have a hose coming
from the radiator, and the other fitting(on the neck itself) would have the hose going to the ground.
At least, this is how I unnerstand it to be....
At least, this is how I unnerstand it to be....
Joel Adams
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Lifetime MemberHot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
Adams' Apple said: On this tank, the two lower fittings would be tied into one of the heater hoses. The upper fitting on the tank close to the neck would have a hose coming from the radiator, and the other fitting(on the neck itself) would have the hose going to the ground.
At least, this is how I unnerstand it to be....
At least, this is how I unnerstand it to be....
yep
the question I am trying to answer is which heater hose.
the 3/4" line between the core and water pump
or
the 5/8 line between the core and intake.
I have a couple of drawings for 69 to 72 expansion tanks and they show the tank inline with the hose from water pump to heater core. if you pm me with you email I will send you what I have
I asked the same question Feb. 2011. I never got the answer to which hose went to the bottom of the Expansion tank, or does it make any difference. If you find out please let me know. I still haven't installed it on my 68.
in Forum: C3 Cooling and Heating Systems
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