delco1946 Posted March 30, 2019 Share Posted March 30, 2019 I know a lot has been written on this, but i still can't seem to find an answer to my question. In anticipation of summer, i want to be able to stop the flow of coolant into my heater. My 1955 ford has a similar problem in that already warm outside air flowing into the cabin gets hotter. Its very unpleasant! I want to avoid this on my truck. I have the basic heater system. Do i put an open/closed valve in the heater hose line? Which one? both? do i have create a system to allow continuous flow through the hoses for the engines health (but effectively allow the heater to be cut off? What valves will hold up to the fluid corrosively, pressure, and hot temperature? Finally, is it possible to add actual ac in the future? I don't really care if it comes out of the defrost/floor vents ( i don't have face vents). Link to comment Share on other sites More sharing options...
jstone4646 Posted March 30, 2019 Share Posted March 30, 2019 I do not know if this can be done easily per say, but instead of adding bypass valves that could potentially fail, you could just completely disconnect (and plug to keep debris out) the hoses running to the heater core and use a joining connector to just completely bypass it. Then when the cold begins to come back around just normal it all back up? Just a thought! Link to comment Share on other sites More sharing options...
delco1946 Posted March 30, 2019 Author Share Posted March 30, 2019 I do not know if this can be done easily per say, but instead of adding bypass valves that could potentially fail, you could just completely disconnect (and plug to keep debris out) the hoses running to the heater core and use a joining connector to just completely bypass it. Then when the cold begins to come back around just normal it all back up? Just a thought! That is a thought. I wonder though, to do that, id have to drain the coolant each time right? Also, i admit as low tech as I'm trying to go, i would like to simply be able to pop the hood and turn the system on or off depending on weather. Link to comment Share on other sites More sharing options...
jstone4646 Posted March 30, 2019 Share Posted March 30, 2019 That is a thought. I wonder though, to do that, id have to drain the coolant each time right? Also, i admit as low tech as I'm trying to go, i would like to simply be able to pop the hood and turn the system on or off depending on weather. Well I do not know for sure if you would need to drain it. Assuming the motor was cold when you do the swap you may not need to flush the coolant. You would probably spill or loose a little, but again if the motor was cold, and since you are on the top end of the motor, if you keep the hoses as elevated as possible, gravity should keep it all in place. But you do bring up a good point, you would not want to leave stagnant coolant in the heater core all summer long, so you would likely want to put some low pressure air through there to clean it out? Sorry I do not want to give bad advice, but it was just a quick thought! Link to comment Share on other sites More sharing options...
delco1946 Posted March 30, 2019 Author Share Posted March 30, 2019 Well I do not know for sure if you would need to drain it. Assuming the motor was cold when you do the swap you may not need to flush the coolant. You would probably spill or loose a little, but again if the motor was cold, and since you are on the top end of the motor, if you keep the hoses as elevated as possible, gravity should keep it all in place. But you do bring up a good point, you would not want to leave stagnant coolant in the heater core all summer long, so you would likely want to put some low pressure air through there to clean it out? Sorry I do not want to give bad advice, but it was just a quick thought! i hadn't thought of that. I wonder if disconnecting the heater could hurt it? If i drained it, could its guts rust? Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 30, 2019 Share Posted March 30, 2019 Well I do not know for sure if you would need to drain it. Assuming the motor was cold when you do the swap you may not need to flush the coolant. You would probably spill or loose a little, but again if the motor was cold, and since you are on the top end of the motor, if you keep the hoses as elevated as possible, gravity should keep it all in place. But you do bring up a good point, you would not want to leave stagnant coolant in the heater core all summer long, so you would likely want to put some low pressure air through there to clean it out? Sorry I do not want to give bad advice, but it was just a quick thought! You might want to check out this thread which discusses that. And then this page: HVAC Systems and the Heat Shut Off tab and then the Vacuum tab, which is the only one I've populated. But there are manual valves that will easily do the job. I'll try to remember to put some info and pictures on the Manual tab on that page tomorrow. And all of the engines have a bypass system in the cooling system, so you can just put a valve in one of the heater hoses, and it doesn't matter which one. Link to comment Share on other sites More sharing options...
Frank Wyatt Posted March 30, 2019 Share Posted March 30, 2019 You might want to check out this thread which discusses that. And then this page: HVAC Systems and the Heat Shut Off tab and then the Vacuum tab, which is the only one I've populated. But there are manual valves that will easily do the job. I'll try to remember to put some info and pictures on the Manual tab on that page tomorrow. And all of the engines have a bypass system in the cooling system, so you can just put a valve in one of the heater hoses, and it doesn't matter which one. I agree with Gary in I like the Four Seasons valve{http://www.napaonline.com/en/p/BK_6601294} which recirculates the coolant when bypassing the heater core. It can also be found on some Fords like the Explorer if I remember correctly. When ever I finaly get around to replaceing my heater core, I'm thinking of useing an electric vacuum control vave like this one to operate it http://www.summitracing.com/parts/vta-11542-vus. You can get the bypass valve here also http://www.summitracing.com/parts/fss-74809. they also list the Motorcraft one http://www.summitracing.com/parts/mof-yg350?rrec=true. Link to comment Share on other sites More sharing options...
Steve83 Posted March 30, 2019 Share Posted March 30, 2019 Do i put an open/closed valve in the heater hose line? Which one? both?The 4-way valve in both lines is best, for several reasons. https://supermotors.net/getfile/992200/thumbnail/38htrvlv.jpg But there are many others available.do i have create a system to allow continuous flow through the hoses for the engines health (but effectively allow the heater to be cut off?That's what the 4-way does, because modern vehicles require flow through that circuit any time the engine is running, for several reasons. To determine if yours requires it, just look at what's in that circuit. If you see any sensors, then they can only work when coolant is flowing past them.What valves will hold up to the fluid corrosively, pressure, and hot temperature?Any of the dozens of valves made for that purpose.Finally, is it possible to add actual ac in the future?Of course. There are many options, including several configurations that Ford offered from '80-96....use a joining connector to just completely bypass it.It's easier to just disconnect opposite ends of the hoses, and then connect one of them back to the open nipple on the engine....id have to drain the coolant each time right?No, you'd barely lose any coolant each time, once you practiced your technique a few times....you would not want to leave stagnant coolant in the heater core all summer long...Stagnant or flowing is irrelevant - coolant ages at exactly the same rate no matter what (when it's in contact with metal - not in the plastic bottles).If i drained it, could its guts rust?No, for several reasons - primarily because only Iron/steel "rusts", and the heater core is brass (Copper/Zinc alloy). It would only corrode (VERY slowly) if you left it open to the elements for years. If you connect that 2nd hose back to the heater core, it won't corrode (internally) fast enough to detect at all; whether full of coolant, or dry.And all of the engines have a bypass system in the cooling system...I'm not sure what you mean, or what you're saying gets bypassed. But simply blocking the heater loop on a 300ci/4.9L will cause problems because the coolant will have nowhere to flow when the t'stat is closed....you can just put a valve in one of the heater hoses, and it doesn't matter which one.It's always better to put it on the high-pressure side; putting it on the return side will cause high pressure inside the heater core, which will lead to leaks. Link to comment Share on other sites More sharing options...
delco1946 Posted March 30, 2019 Author Share Posted March 30, 2019 Do i put an open/closed valve in the heater hose line? Which one? both?The 4-way valve in both lines is best, for several reasons. https://supermotors.net/getfile/992200/thumbnail/38htrvlv.jpg But there are many others available.do i have create a system to allow continuous flow through the hoses for the engines health (but effectively allow the heater to be cut off?That's what the 4-way does, because modern vehicles require flow through that circuit any time the engine is running, for several reasons. To determine if yours requires it, just look at what's in that circuit. If you see any sensors, then they can only work when coolant is flowing past them.What valves will hold up to the fluid corrosively, pressure, and hot temperature?Any of the dozens of valves made for that purpose.Finally, is it possible to add actual ac in the future?Of course. There are many options, including several configurations that Ford offered from '80-96....use a joining connector to just completely bypass it.It's easier to just disconnect opposite ends of the hoses, and then connect one of them back to the open nipple on the engine....id have to drain the coolant each time right?No, you'd barely lose any coolant each time, once you practiced your technique a few times....you would not want to leave stagnant coolant in the heater core all summer long...Stagnant or flowing is irrelevant - coolant ages at exactly the same rate no matter what (when it's in contact with metal - not in the plastic bottles).If i drained it, could its guts rust?No, for several reasons - primarily because only Iron/steel "rusts", and the heater core is brass (Copper/Zinc alloy). It would only corrode (VERY slowly) if you left it open to the elements for years. If you connect that 2nd hose back to the heater core, it won't corrode (internally) fast enough to detect at all; whether full of coolant, or dry.And all of the engines have a bypass system in the cooling system...I'm not sure what you mean, or what you're saying gets bypassed. But simply blocking the heater loop on a 300ci/4.9L will cause problems because the coolant will have nowhere to flow when the t'stat is closed....you can just put a valve in one of the heater hoses, and it doesn't matter which one.It's always better to put it on the high-pressure side; putting it on the return side will cause high pressure inside the heater core, which will lead to leaks. So i think this is the same kind of valve linked to before. I don't think i can use this - its vacuum operated and from what i can tell connects to your dash ac controls - which i do not have. I was hoping someone knew of a mechanically actuated valve to be simple. e.g. i pop the hood and turn a knob or two. And I know AC can be added Anything is possible. I was hoping to get an idea of what level of effort is required. Can i just switch out some parts or is it going to be major headache? Link to comment Share on other sites More sharing options...
Steve83 Posted March 30, 2019 Share Posted March 30, 2019 ...its vacuum operated and from what i can tell connects to your dash ac controls - which i do not have. I was hoping someone knew of a mechanically actuated valve to be simple. e.g. i pop the hood and turn a knob or two.Why wouldn't you have the knob in the cab, so you don't have to open the hood? Vacuum IS mechanical. But if you don't want to run a vacuum line (which is pretty simple, cheap, effective, & reliable when done properly), you can simply cut/break the vacuum motor off that valve, and hook a cable to it. Or a knob if you like opening the hood. ...what level of effort is required. Can i just switch out some parts or is it going to be major headache?IDK how to answer that - it depends on how you define your levels, and whether you consider switching some parts to be a major headache. But I don't know what tools you own & know how to use, or how much work area you have available, or what experience you have. Parts DO have to be added & or switched - yes. None of them require heavy lifting or advanced skills. You might also have to cut some thin sheet metal - I can't say for sure because I don't know exactly how your truck is built, or what condition it's in right now. If you get a complete working sealed refrigerant system from a newer donor truck, you don't even have to pay a pro for evac & recharge. I've swapped a whole A/C system on an F150 in my driveway in ~1 hr using cordless tools. Read this caption, and follow the links in it for more info & pics: https://supermotors.net/getfile/994176/thumbnail/ac95b58.jpg Link to comment Share on other sites More sharing options...
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