2.3L ('83-'97) Heat is always on even when system is in off position

[Sweersa]

For the past week or so I noticed my heat is on, even when the middle dial set to blue instead of red (my Ranger was never equipped with AC) and with the left dial turned all the way down, and the far right switch set to the off position. I can still feel hot air coming through the vents. Not a major issue in October in Michigan, but it gets pretty hot in the cab during the day even with the windows down.

Any ideas what this could be? I have not ripped into her yet to look. I assume it could be the blend door actuator, or a vac line. 1997 2.3 2x4 with no AC. (Never equipped with AC from factory)

 

[franklin2]

Both the older rangers I had did this same thing. I adjusted the cable for the door, etc. It always leaked. Like you said not much of a problem till summer comes with 90+ degree heat. On both I ended up putting a manual shut off valve in the heater hose to cut the water off in the summer. I just turned it back on a couple of weeks ago, starting to get chilly mornings. With the water flow off, you do not have to worry about air running through the hot heater core and leaking into the cab.

 

[SenorNoob]

Didn't Rangers have an automatic version of that on some years?

 

[franklin2]

Didn't Rangers have an automatic version of that on some years?

A little bit later, I want to say in the later 90's they did. The valve they used is a good retro fit on the larger trucks with the same problem, their doors leak also and lower the A/C performance. You can run a vacuum tee into the recirc door actuator and hook that to the ranger water valve, and it turns the water off to the heater core when you put the dash switch to "max". Works great.

But, it doesn't work that well on the earlier rangers with the smaller engines. I tried this valve on my BII when it had the 2.8 engine. I now know why the first rangers came out with all mechanical HVAC controls. After I hooked the later water valve up it worked well, I just had to get under the hood and move the vacuum line around manually. But I pull a mountain everyday to work, and noticed the vents getting hot when doing so. I had the little 2.8 wide open everyday, and it lost vacuum when doing so and the water valve would relax and let hot water through to the heater core. So I took it off and put the manual valves in place.

Looking back on it, I could have installed a vacuum reservoir and check valve to try and keep the valve supplied with vacuum, but I do not think it would be worth the trouble. Little rigs and patches have to be kept simple.

 

[franklin2]

I looked up a 1998 ranger with a 4.0 engine, here is the water valve.