Joe Flanagan Posted October 10, 2011 Report Posted October 10, 2011 I just hooked up my heater core to check for leaks, etc. There is only a slight leak at the inlet tube, otherwise it's tight. The fins do not heat up, however. I installed the two-tube control valve that is made by Four Seasons, the one that looks like the original and passes through the firewall. It is controlled by the original knob and cable. I let the engine get up to temperature before I opened the valve. Once it was up to about 170 degrees, I opened it up. The hose to the heater core gets hot. The inlet tube gets hot. But that's it. Before installing the heater core I ran water through it and it came out clean and seemed to be flowing very well. Could the thing still be clogged in its innards? Maybe it just needs to be boiled out. Quote
Rusty O'Toole Posted October 10, 2011 Report Posted October 10, 2011 (edited) Do you mean the hot water is flowing through the heater core but no heat comes out when you turn on the fan? The air comes out cold? Sounds like the water flow is restricted either the valve is not opening completely or the core is plugged but that does not seem possible after your careful work. The other possibility is an air lock. Sometimes the air does not all bleed out of the core due to the way the hoses run. The outlet from the heater should be the upper pipe. If necessary you can pull the hose nearly off the pipe and drill a tiny hole in the brass pipe. Then with the engine running pull back the rubber hose and let the air out of the core, when water comes out quickly shove the hose on and tighten the clamp. Edited October 10, 2011 by Rusty O'Toole Quote
Joe Flanagan Posted October 10, 2011 Author Report Posted October 10, 2011 Thanks, Rusty. Fan and duct are not installed yet. The heater core itself is cool to the touch. I watched the operation of the new valve and the open-close mechanism moves through its full range. It could be that the core is plugged. I think I got this one out of a salvage yard and I just ran some water through it with the hose and then took a stab in the dark and installed it. So I guess it could be clogged, though when I ran water through it, it came out the other end just fine. The outlet hose from the core to the water pump also remained cool to the touch. I might try drilling a hole in the brass tube. Quote
DJ194950 Posted October 10, 2011 Report Posted October 10, 2011 hi joe. how about, with motor off, disconnect hose from heater to heat control valve, pinch off hose with some needlenose vicegrips . have a clean conrainer avail. start motor put hose end into container and release vise grips to check for flow to control valve. if you have flow, heater core is ok. if not core is plugged. if you have flow reconnect hose to valve. disconnect hose from heater control output side to block at the block. repeat the container/vise grip flow test. see flow with heater turned on and off position. could the valve be off in the on position? if i remember right 4 seasons made very simular valves- 1 where the control PULLED opened the valve and another that PUSHED the valve was open. i looked at the one on my valve changeover and it is a valve that needs to be pulled at the cable to open with the factory control. going to need that heater! I expect your car to on the road soon. Quote
Joe Flanagan Posted October 10, 2011 Author Report Posted October 10, 2011 Thanks, Doug. I think I have the on-off thing correct. The valve matches the operation of my stock heater control. First I ran it with the valve in the off position. The hose from the valve to the heater core remained cool. Once I opened the valve, the hose got hot. The inlet tube on the heater core got hot, too. But the heater core itself stayed cool, as did the outlet hose going back to the water pump. Quote
Rusty O'Toole Posted October 11, 2011 Report Posted October 11, 2011 Could you arrange some kind of fan to blow through the heater core? It is hard to tell by touching the core, I have tried this with rads and you don't seem to feel the heat unless you touch the tank. But the air gets hot when you blow through. Quote
Robert Horne Posted October 12, 2011 Report Posted October 12, 2011 Worked on my heater from my 38 Coupe yesterday. I put in some vinegar/water solution the day before, 1 quart. I hooked up a water hose and flushed it out. I filled with water, attached a bike inner tube, added 5 lb of air pressure to check for leaks. Have 1 very small leak at the drain plug. I find a look of mud from the hornets in so much of my stuff I am working on. Spiders can clog up hoses also. Quote
Robert Horne Posted October 12, 2011 Report Posted October 12, 2011 Here is my bike tube tester. The heater core holds 1 quart of fluid. Quote
Joe Flanagan Posted October 12, 2011 Author Report Posted October 12, 2011 Ingenious. Haven't gotten back around to mine. I want to eliminate the valve first. It's brand new, so I don't think it's likely, but you never know. Quote
oldmopar Posted October 12, 2011 Report Posted October 12, 2011 Friend of mine took a heater core for his 42 dodge truck to a radiator shop to have it cleaned and checked not sure what the cost was. Quote
Cpt.Fred Posted October 12, 2011 Report Posted October 12, 2011 cunning setup, robert we did the same to my radiator last year, a big bathtub full of water, some plugs and a compressor. this was preceeded by a treatment with industrial acetic acid. helped a lot! Quote
Joe Flanagan Posted October 13, 2011 Author Report Posted October 13, 2011 And now from the Department of Unsolved Mysteries: Today I pulled one of the hoses going to the heater control valve so I could check the operation of the valve itself. It worked perfectly. I reattached the hose and ran the engine. To my surprise, the heater core heated up nicely. Hot all the way through. I don't know what happened the last time I tried it but I ran the engine for quite some time (with the valve open, I'm positive) and it never got hot. I do have a very minor leak at the inlet tube. I'd like to take a whack at that myself rather than take it to a shop. Does anyone have experience with repairing these? Quote
Robert Horne Posted October 13, 2011 Report Posted October 13, 2011 I have not done any copper plumbing repairs in many years. Today I bought some new solder and repaired the small leak in my 38 heater core. There was a steel plug in the core that leaked and would not come out. I drilled a hole in the plug, put in a brass bolt as a plug, from a toilet, soldered around the plug, and there seems to be no luck this evening. Quote
bamfordsgarage Posted October 14, 2011 Report Posted October 14, 2011 ...there seems to be no luck this evening. Don't get discouraged — this happens to all of us as we get older. Tomorrrow could be a better day. Quote
Plymouthy Adams Posted October 14, 2011 Report Posted October 14, 2011 hopefully it went well and that was a typo..as in, it had no leak as of this evening.. Quote
RobertKB Posted October 14, 2011 Report Posted October 14, 2011 Here is my bike tube tester.The heater core holds 1 quart of fluid. Great tip! Thanks for posting that. I think a lot of members will make use of your idea! Quote
Don Coatney Posted October 14, 2011 Report Posted October 14, 2011 Today I bought some new solder Is new solder better than old solder? If so why? I have a bunch of old solder. Quote
Jim Yergin Posted October 14, 2011 Report Posted October 14, 2011 Don, I think I have heard that old solder never dies, it just fades away. Jim Yergin Quote
Robert Horne Posted October 15, 2011 Report Posted October 15, 2011 Is new solder better than old solder? If so why? I have a bunch of old solder. I have not had any solder in many years, had no buy new. Quote
Robert Horne Posted October 15, 2011 Report Posted October 15, 2011 Don't get discouraged — this happens to all of us as we get older. Tomorrrow could be a better day. Sorry, my typing is not as good as my solder repair. The repair held up under 5 lbs of pressure all night. Quote
Robert Horne Posted October 15, 2011 Report Posted October 15, 2011 I installed my heater today. I used a 12 volt to 6 volt reducer to run the fan. It only has 1 speed. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.