The All Too Common Heater Problem
FTE Chapter Leader
Joined: May 2002
Posts: 42,875
Likes: 3,188
From: Fraziers Bottom, WV
You reported that the blend door in the heater box (under the hood) is good.
My question; is the cable from the controls to the blend door actuator working? I had the same problem and the cable was bent under the dash and the blend door did not move! I had great heat, but it was 85 degs out side and I was hot!
My question; is the cable from the controls to the blend door actuator working? I had the same problem and the cable was bent under the dash and the blend door did not move! I had great heat, but it was 85 degs out side and I was hot!
Thread Starter
|
Elder User
Joined: Feb 2003
Posts: 871
Likes: 0
From: Coleman, Wisconsin
Here's everything I know so far:
Water Pump Good
Hoses Good & Hot
Heater Core Good
Blend Door Shuts TIGHT
Cable Closes Door TIGHT
Nothings Plugged
What I don't know is: Why isn't the pump pumping enough fluid into the core? It should shoot out the hose a mile long. I guess there's no more questions I can ask on here, I'll have to start going to church.
Water Pump Good
Hoses Good & Hot
Heater Core Good
Blend Door Shuts TIGHT
Cable Closes Door TIGHT
Nothings Plugged
What I don't know is: Why isn't the pump pumping enough fluid into the core? It should shoot out the hose a mile long. I guess there's no more questions I can ask on here, I'll have to start going to church.
Moderator
Joined: Jan 2001
Posts: 57,027
Likes: 2,763
From: Virginia
What I would do in your case is replace the heater core again. Even though it's flowing water, it may not be transferring the heat correctly. If possible, can you rig it up so you can feel the heater core to see if it's hot? It really couldn't be if you have airflow?
Posting Guru
Joined: Sep 2003
Posts: 1,002
Likes: 1
From: Right Next to U
There is a valve on the heater hose that could be defective, its supposed to allow coolent in to the heater core, its sometimes very close to the inlet side of the hose. Check it to make sure its working, also some fans cages will spin correctly in low but won't spin very fast on high if the allen screw came loose on the fan cage. Thermostat has to be correct (180 to 195) Coolent has to be 50/50 mixture, too much coolent won't get hardly any heat....
Senior User
Joined: Dec 2003
Posts: 118
Likes: 0
I don't know if this is your problem but I had a similar one. Guy who i brought truck off had 160 degree thermostat (heater blew cold air) I changed it to 180 deg. thermo, very little change, so i put a 195 in and know it works fine. Everything was working fine (hot hoses, closed doors et. etc..) with 160 and 180 thermostats. Just a thought anyway.
Chris
Chris
Posting Guru
Joined: Sep 2003
Posts: 1,002
Likes: 1
From: Right Next to U
If the water pump isn't working, there would not be any movement of coolent in the engine or heater core, in fact, you'll have more heat then you'll ever need...and the engine would certainly be a large paperweight. If you have air still in the heater core and its trapped, it would not get HOT enough for heat warmth. You can disconnect and plug the heater hoses, and the engine would still be able to run properly. If you're getting a sweet smell and water vapor around the inside windows, you have a small leak in the heater core someplace. You should get some pressure (firm) on the rad. hoses. Rad cap should be from 14 to 16 pound cap and in good working order. These are some other facts about what you should know in order to get the warmth of the heater in the cab. and a good flush of the rad. system would confirm if you have a blockage someplace in the heater core.... and would help your engine to run cooler in the summer and fall. What does your reading on the temp gage read? Have you tested the temp of the coolent with a thermometer?
Thread Starter
|
Elder User
Joined: Feb 2003
Posts: 871
Likes: 0
From: Coleman, Wisconsin
My dad measured the vanes on the old waterpump and there was greater than or equal to .050'' wore off compared to the new one. He said judging by his experience with hydraulic pumps on 'A' John Deeres, this would probably not affect the volume, meaning the radiator would cool enough. But with over .050'' tolerance between vane and pump housing it couldn't pump any significant pressure which is needed to push enough volume to the heater core because the hoses are so much smaller. Sounds logical to me, why the radiator works but the core doesn't. I guess I'll just have to put the new pump on and find out for myself. Thermostat can't be too cold because my heater worked fine before, it just got worse and worse until there was nothing. Locknkey, there is no valve in the heater hose.
Senior User
Joined: Nov 2004
Posts: 140
Likes: 0
From: Troy, MI
where did you get the newer heater core from? i would only suggest the dealer units. i too believe the waterpump is probably not at fault, if its flowing enough to cool the motor its flowing enough for the heater core. ive had many WPs go bad on me with no change in heat. and the thermostats do play a big part in how much heat you will have, make sure you have a good working stock thermostat. ive put 160deg thermos in all my cars and lost a ton of heat because of it. good luck.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / Worst Features Of The 2025+ Ford Expedition
Brett Foote
10 Ways Ford is LOSING to the Competition
Joe Kucinski
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
Thread Starter
|
Elder User
Joined: Feb 2003
Posts: 871
Likes: 0
From: Coleman, Wisconsin
I think I got it from carquest. That's usually where I get those kinds of parts from. If the new waterpump doesn't do anything, then I'll try the core again. I just want to get my truck on the road again, heat or no heat.
New User
Joined: Jun 2004
Posts: 7
Likes: 0
Hey Boss when you figure it out let me know. I have been having the same problem with my 86 ranger. Ive done everything you have except the water pump and still only have warm air on low. I even put card board in front of my rad and it doesnt get any warmer.
More Turbo
Joined: Mar 2002
Posts: 508
Likes: 2
From: Easthampton, Ma.
Quick question: After letting your truck idle in the driveway for 20 minutes, with the heater on high, can you hang on to both heater hoses without burning your hands? Are both hoses the same temperature?
Steve G.
Steve G.
Freshman User
Joined: Oct 2004
Posts: 46
Likes: 0
From: spokane, wa
thats good you figured it out. im having the same problem with my 89 bronco, i havent tested everytihng you have , but i might start with a new water pump anyways , im not sure how old it is , but the previous owner wasnt very good at any maintance , and if that doesnt help, im getting a new heater core . i placed a smaller pice of card board in front of my radiator the other day jsut to give it a test , and it helped , not a lot , but it helped . so im going to try a larger peice today to see if theres any signifagant improvement. i have replaced the thermostat, so thats not the problem.
my 1986 f-150 heats there no tomorrow , thats why i started thinking there was something wrong with the bronco.
airrikk17
my 1986 f-150 heats there no tomorrow , thats why i started thinking there was something wrong with the bronco.
airrikk17