Got a 2001 F150 and it is apparent that the heater core is leaking out the AC evap/condensate drain in the firewall. Don't have the time, money, or help right now to do the dash removal to replace the heater core. So, to get the truck up and running, I was just going to cut the heater hoses & do a "U" shaped bypass on the hoses going to the the heater at the firewall, and get the truck moving again. I would also (temporarily) cap off the hoses coming from the heater core at the firewall to prevent anything getting in there. This way I could drive the truck until I have the time/money/help to do the fix correctly & completely. Use something like what is shown here.
In looking on the internet, I saw some info on a heater cable operated heater bypass which if I understand it correctly, it allows you to manually close the valve and take the heater core out of the cooling system. Apparently people have been putting these units in to help the air conditioning cool the inside of cars better because the heater core doesn't have the hot antifreeze circulating next to the AC evaporator in the dash. See picture below. Thoughts? Anyone?

 

pops - I may be wrong, but isn't there a valve there that cuts off hot fluid to the heater core when you turn the heater off? It used to work that way back in the day, but maybe now, with climate control, there is always some fluid circulating. If that is the case, I don't see why what you are proposing would not work. The heater core is not essential for cooling the engine, so it should be able to be bypassed completely.

- Jack

 

That looks absolutely ignorant, sorry to be blunt but why would you go through all this hassle all this extra effort when you could just leave the hose and bypass the heater core anyway at minimal effort and cost???

 

Thanks everybody. The reason I am wondering if it would be smart to put in a bypass valve now instead of just simply cutting the heater core out of the system (using the "U" shaped hose & clamps) is that it would allow me to get the truck running right now. And, if I understand how these bypass valves work, once I get the heater core changed out, then to get it back into the system, all I would have to do is move the bypass valve back to fully open by pulling/pushing on a cable. Furthermore, in the HOT summer months where I live, the AC struggles to get the inside of the cab cool, and there are many who install these bypass valves just to help the ac work better. So, I am wondering if these bypass valves work as described, and since I have to cut the heater hoses anyway to get the truck running now, then would it be a good idea to put in a bypass valve now for all the benefits described above. And I am wondering if anyone here has done the same thing? Never having any experiences with these type of valves, I admit I may not know if this will work as I hope, and so I defer to the more knowledgeable people here. Thanks in advance for all advice!

 

Oldpops, How did this turn out for you. Doing a heater core right now on my '02 and am considering a bypass valve to assist the AC performance. Thanks in advance!