My son just bought a 94 ranger with 140k miles. It runs ok but he has no heat in the cab. Checking the coolant tonight and found it to look like chocolate milk! So a flush is definitely in order but that still doesn't explain the no heat issue. Both of the heater hoses going to the firewall are not warm at all and feel like they are empty?? What causes these hoses not to get hot? Also the t-stat was just changed.

Thanks!
Mark

 

Almost sounds to me like the radiator is plugged up and you're not getting any flow... What does your temp gauge say after it's warmed up?

 

I'm having the same problem, except I get heat about half the time. I flushed the fluid and it didnt help anything. My Temp gauge reads normal like it should.

 

Wanta, try giving the cooling system a good flushing. It sounds like the entire system is plugged up.

 

do a good flush as stated. Trucks with AC have a heater control valve. this valve uses a vacuum and shuts off flow at the heater hoses to the heater core. Check that it is working. You might want to swap in new heater hoses. they can get clogged up. back flush the heater core too. I recommend Motor craft tstats.

 

Thanks for the replys....going to try and flush the entire thing this afternoon after work. I'm really thinking that it's clogged up because last night I opened the petcock on the radiator and there was barely a dribble of coolant coming out.

If it is clogged, what is the best method of flushing the system? I was thinking of putting a tee in the heater hose a doing it from there.

The temp gauge reads about middle of the "normal" range when it's warmed up.

Where is the heater control valve located and is this something I can test at home?

Oh, and I forgot, it's a 3.0 V6, 2wd, A/T.

 

Napa sells a Product by MAC that works good for flushing.I would spend the $10 for new heater hoses and change them first. I bet they are filled with crap. Your truck sounds pretty nasty. I would disconnect the heater hoses at the heater core and connect them. that way the crap will not clog up the core any more than it is already. You can back flush the heater core separately. I would pull the bottom radiator hose off and flush that all out before I started the truck. Get as much crap out before you flush the engine out when it is running. You will have to run the truck to full operating temp with water in a few times to get all the crap out. the heater control valve should be inline with the heater supply hose you can see if it is opening an closing when the AC is on. Go to Rockauto.com and you can see what it looks like. Ideally removing the T-stat during the flush is best not necessary. The goods news is that if your heater core is trashed it is a cheap and easy fix. Any Rangers after 1994 you have to pull the dash to replace the heater core.

a good signature helps a lot. If from the 1st post you had a detailed signature that included if you had AC and what transmission you had we would have know if you have a heater control valve and if you had a 5 speed we would know that pulling the radiator is a POC.

 

Pretty sure its the heater core now, flushed entire system really good and refilled. After it reached normal temp I felt the heater hoses to and from the core. The one going to the core was hot and the other was cold. Have one ordered, and it'll be in tomorrow.

Thanks to everyone for your help!!

 

Well it was a very clogged eater core! Changed it out and burped the system, all good now.

Thanks to all for the help!

~Mark

 

Yes I would say it's your heater core. Years ago I had a chevy S 10 & had the same problem.

Good luck on the replacement.

 

Thanks all for the tips & insights.

I too went through the entire cycle of replacements -water pump & thermostat.
I could not get any flow through the core. I COULD pass water directly from a garden hose through the core & no leaks were noticed inside. I put a ~6" section of clear plastic hose in-line with the heater core line back to the thermostat housing. This proved the no flow. I put the front end up on ramps & this got the 'air lock' out of the core & the water flowing. The heat is good.
I hope this helps someone else from all the testing & guesswork.

 

I put in a new heater core and never had heat since. Saw this thread and went to checking. Thought I would check the valve for obstructions. Now my valve is bad. The nipple broke as I was pulling the hose off. Now I will know if it was the valve?

 

Sounds like you need to replace the valve anyway so if, after you replace it you get heat, I'd say that would be a good indicator the valve was the culprit.

 

I was sort of mad at myself for breaking it. But it has to be original so it was probably due for a replacement . Plus I found Oreilly has it for less than $30.

This darn thing just keeps messing with me. Put in a new heater core this spring, new clutch slave cylinder and clutch during the summer. Drove it home from the shop and the ignition actuator crapped out. Got it replaced and now it's the heat.

 

Thanks for the feedback. Its good to lnow that your colling system problem is solved