Heater hose size ??
Thread Starter
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Heater hose size ??
1976 Coupe, what is the proper size for the heater hoses, and are they both the same or different? I also would like to put in a manual shut off valve so if someone has a link to one that would be nice. Some kind of small unobtrusive gate valve, not a big clunky ball valve. This is all I've been able to find so far, and I dont know if it's even the right hose size:
http://www.nostalgicairparts.com/air...-valve-385.php
Thanks!
http://www.nostalgicairparts.com/air...-valve-385.php
Thanks!
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Hose is measured by the ID- one is 5/8 and the other is 3/4. There is a raft of different style valves around. Pick the one you like and go with it. Take a look at Lowe's or Home Depot too, they have several different styles there. I think an inline ball valve would be the thing if you can find one for the right price.
Thread Starter
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Can someone tell me which one goes to the manifold and which goes to the water pump? Sorry, but this car hasnt had the heater core hooked up (for the reason you might guess) since way before I got it.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I think the 3/4 hose runs to the water pump. I've got CRS so don't hold me to it. the difference in sizes, the 5/8 hose will fight you going on the 3/4 nipple but the 3/4 hose will slide on either one..
Safety Car
Joined: Jun 2004
Posts: 4,372
Likes: 223
From: Beecher Illinois
5/8" goes to the intake manifold fitting and is the one the factory put the shutoff valve on.
Last edited by KapsSA; Dec 21, 2008 at 07:44 PM.
Instructor
Joined: Sep 2008
Posts: 222
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From: penngrove ca
I have 76, 350 and I belive the 5/8" goes from the intake to the heat control valve; then out of the C valve to the heat core; the 3/4" line goes from water pump to large fitting on heat core. There is also a small vac. line on the top of the c. valve that goes into the cabin on the temp contol switch.
If you install a shut off you should make sure your valve is rated for hot water.
If you install a shut off you should make sure your valve is rated for hot water.
Thread Starter
Pro
Joined: Oct 2005
Posts: 541
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From: Freeport FL
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Joined: Aug 2006
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Heater shutoff valve
If you have a vacuum line out there you can get the correct type shutoff valve at Advance auto, part # 74610. PG.
