Block off heater hose ?
Thread Starter
Race Director
Joined: Jan 2007
Posts: 10,684
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From: Danville Illinois
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Block off heater hose ?
How many of you block off the heater hose to the heater?
Thinking of doing this on my 75 to reduce the heat.
Block off inlet or exit? Pros/cons.
Any pics welcome.
Thinking of doing this on my 75 to reduce the heat.
Block off inlet or exit? Pros/cons.
Any pics welcome.
Instructor
Joined: Dec 2006
Posts: 105
Likes: 0
From: biloxi mississippi
i have the hose (2) bocked off on my 78. in deep south MS we dont need heat much. but went to lowes and purcased 2 in line shutoff valves cut the hose,clamped in the shutoffs and if i need the heat i pop the hood switch the valves and instant heat. used the heat last fall at Mid America would also suggest if ou use this method to ever so often open the valves to circulate new fluid through the heater core (makes the core last longer)
Pro
Joined: Feb 2012
Posts: 668
Likes: 21
I put 2 inline ball valves from Home Depot in my 79. It worked so well I can't believe that I didn't do this 15 yrs ago. I plan on by passing the heater core on my 73 in a week or two because now that its on the road I can feel the cabin heat even with the top down.
I have found it's better to block both hoses. One thing I like about this is if I need heat(not that I ever drive it in the winter) all I have to do is open up the valves and in the mean time no more burnt feet.
I also like the suggestion that is directly above mine. If the fitting would come out of my water pump and intake on my 73 I would just put in pipe plugs. I bet I would brake them since they have been in there for 39 years.
I also like the suggestion that is directly above mine. If the fitting would come out of my water pump and intake on my 73 I would just put in pipe plugs. I bet I would brake them since they have been in there for 39 years.
Last edited by superdave269; Jul 4, 2012 at 06:54 AM.
Race Director
Joined: Apr 2011
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From: North of Toronto - Ontario
Added a valve this year. Just did the one line but it made a significant difference in heat.
I tucked it in as tight as I could to the firewall
You can kind of see it here
Mooser
I tucked it in as tight as I could to the firewall
You can kind of see it here
Mooser
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Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
Block off the inlet with this valve. From Four Seasons. Has 5/8 connections. And yes my hose clamps are properly dated.
I recently replaced the original vacuum operated shut off valve so this manual valve may not be needed any more. I plan to test it here shortly. The factory set up will work if the vacuum system on the climate control system is working properly. mike..
I recently replaced the original vacuum operated shut off valve so this manual valve may not be needed any more. I plan to test it here shortly. The factory set up will work if the vacuum system on the climate control system is working properly. mike..
Intermediate
Joined: Nov 2010
Posts: 40
Likes: 4
From: California
I put a valve on my inlet hose this spring. It makes a difference. I have opened it up during brief 'cold snaps' or for defogging after rainstorms. So far no problems. I hope to drive her enough in cooler fall weather to keep the (new) heater core in good shape.
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
From the intake is the supply to the heater core. Think about the flow through the radiator. The thermostat allows the water to flow into the rad.. The water pump pulls the water into itself then pushes it through the block and out the heads into the intake. mike...
Melting Slicks
Joined: Aug 2008
Posts: 2,200
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From: Lehigh county Pennsylvania
I installed a McMaster-Carr.com #4912K99 Miniature Chrome-Plated Brass Ball Valve, Screwdriver Handle, 1/2" NPT Female X Male Connection and a Russell 1/2" NPT 45 degree hose adapter...I can turn it on/off using one thin dime. No need to carry around a screwdriver.
You might need different plumbing depending on the location of your manifold fitting.
You might need different plumbing depending on the location of your manifold fitting.
Safety Car
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From: Madeira Beach, FL
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Mine is disconnected. Kinda counter productive to expect A/C to work with a heater core passing radiant heat through the same ducts simultaneously.
My divertor doors close properly, heat seeps in still through the firewall.
Even passive heat is still felt with the valve style "fix".
My car is warm inside buttoned up on a 30 degree day w/o a heater.
A/C would be more season appropriate for the times I drive the car.
Marshal
My divertor doors close properly, heat seeps in still through the firewall.
Even passive heat is still felt with the valve style "fix".
My car is warm inside buttoned up on a 30 degree day w/o a heater.
A/C would be more season appropriate for the times I drive the car.
Marshal
Pro
Joined: Feb 2012
Posts: 668
Likes: 21
A forum memeber asked me for a pic. They may not be pretty but they work really well. I used 2 natural gas ball valves as they have nice small handles. I'll be installing this set later this week if all goes well. They 1/2 copper for the 5/8 hose the galv. rigid nipples for the 3/4 hose.
