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84 ranger 4x4 interior heat problem

I have replaced water pump, heater core, 190 thermostat, there is no flow problems... Just hardly any flow to core UNLESS I rev the engine high speed... and still just barley warm. System is full no air pockets, Thermostat does open engine stays lower than 190 at all times. Even when totally covered radiator from air flow and have even pinched the top radiator hose to get more flow to heater core. Still just warm air but is warmer. I am thinking I need a water pump that pushes more water and higher thermostat. the heater core only gets warm...I am at a loss... Any Help?
 
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fatherdoug

Tonto Papadapolous
Is there a vacuum operated valve on the inlet to the heater core? It would be inline with the heater hose. I don't know if they still used those in '84. On the older trucks those valves tended to fail, thus not pushing much hot water through the core.

Just a thought.
 
Nope No valve everything is open to water flow. as far as I can see the thermostat should make NO difference as to being open water should flow anytime engine is running. So changing to a higher than 190 might help a little, but I feel it needs a higher pump flow if there is one. I don't know.
 

blacksnapon

Moderator
Staff member
Just for a hoot, swap sides with your heater hoses. I have seen one that this fixed it.
 

jebadiah04

Rooster Snorkler
849
27
How do you know the flow is good?

Are the heater hoses hot?

There's no reason if it's not plugged up to not be flowing. It's either got to be plugged up and not flowing or you are low on coolant or you have an air pocket. Or it would be working.

The system is very simple. If it flows...it works.

Only other thing would be your mixer is messed up. First thing would be to feel the heater hoses to see if they are hot. If they are then I would look towards the mixer. If they aren't hot, u have a flow problem.

I would swap heater hoses at the engine to see if you blow a chunk out if there isn't any flow.

But see as you rev the engine up and it works better, that to me screams low coolant. I hope you are filling the radiator up at the cap and not at the bottle.
 
I think there must be air in the line. Going to try pouring water into heat core directly by the hose to get any possible air out. I am running pretty much just water until I figure out what the problem is...I am going to run her on the hwy and pump this water at high speed for awhile that should get any possible air out. I have been filling by just the radiator NOT resivoir.
 

Beach66Bum

Moderator
Top Poster Of Month
To get rid of air in the system you need to keep the radiator cap off and turn the heater to the high setting, then go outside and look into the rad opening. After a few minutes you should start to see the collant flowing. You will also see little air bubbles too. Once the hoses start to feel quite warm put the rad cap back on. Coolant works two ways also. Keeps from freezing and aids in heating/ over heating. I personally wouldn't just put water in since you can have rust forming pretty quick in the water jackets, thus preventing flow. Have you tied a reverse flush of the cooling system? This will be a good indicator of the condition of the inside, ie. If there is a lot of rusty looking debris coming out. Try this and see if it helps.
 
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Ya I have done all that reversing, cap off radiator, she still has antifreeze in her too. I was told to put a T with a valve in the return line from core and hold it high while letting her run with thermostat open to let all air in system to evacuate then close valve in the T. But I ain't going that route. I will be taking her on the road this weekend after I get her legal and put a new carb on her. This road run should eliminate any air in system and put it in the radiator, where I can top her off. Thanks for your help. I am determined... LOL!
 

jebadiah04

Rooster Snorkler
849
27
just jack up the side of the truck that has the radiator cap and fill it up. put the cap back on, burb all the bubbles out.

by the way, make sure you overflow bottle has coolant in it too.

Simple explanation, when the air/water mixture expands in your cooling system, its forced into the overflow bottle. If you dont have enough water, it will simply push air out, but when it cools back down, it also sucks back in. So you need to make sure it has something it can suck back in thats not just air.

Also, ive seen this before, is your overflow bottle bubbling all the time, like, lots of bubbles? If so, id be thinking you have bigger problems, head gaskets, cracked head or block. Seen that before too, just pumps air into the cooling system.
 

smokey

Hitech hillbilly
Staff member
You didn't say which engine is in this one. Could be a 2.3 or the 2.8.
The 2.8 has a thermostat under the engine also. The 85 2.3 ranger I had to be parked up hill to bleed the cooling of air while filing it up.
 

jebadiah04

Rooster Snorkler
849
27
Oh..hell I thought he meant f-150 ranger. Lol
 
Took her on the road today for a run and she pushed hot air good, the radiator is still almost full maybe 1/2 3/4 inch below top just a little air in system. So I guess problem is solved. But still just little warm @ idle. I'm going to sheet off front of radiator when winter is in full force, I'll drain some water out and bring her to -20 and keep n eye on level and adjust accordingly. The engine is a 84 2.3 L. Thanks everyone for your help.
 
Took her on the road and finally got some good heat. Radiator level dropped about 1/2 inch to 3/4. will be draining some water out and refilling to -20 and top off via reservoir. I'll put a for sale sign in front of radiator to block air flow when cold hits hard. THANKS GUYS!
 

smokey

Hitech hillbilly
Staff member
My 85 2.3 was cold natured at idle also. Itt threw good heat above idle. I had stick I wedged between the seat and the gas pedal to get a fast idle to warm up and defrost the widow off in the winter.
 

jebadiah04

Rooster Snorkler
849
27
My 2.3 was the same way.
 
heating is solved

Thanks Everyone for the help.... Heating is working fine. Just needed the air out of the system, I guess... I have been driving her a bit now for awhile and shes doing fine.
 
The fluid is always full reservoir full, all the lines are clear new heater core, 160 thermostat, New water pump. She blows out warm air now, but hardly any at a idle. I just purchased another pump online A Cardone W/FINGER vanes. Going to see if it will pump better than those round vaned pumps...
 
I thought is was working anyway........I am changing pumps today to a full finger vane pump, in the hopes it pumps more water. Everything is free flowing no ex-strictions anywhere! I'll will try this and see what happens. she heats fine when going down the highway at speed, but at an idle cold air. If this does not work all I can think off is to restrict the water flow to the engine itself somehow but am afraid during the summer it will over heat..:hammer:
 
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well that didn't work either blows cold air at hwy speeds too. ill get air out of system like before and I will just have to live with this idle problem. I was hoping the finger vane pump would push more water. This ranger is the worst rig I've played with I am about to sell it.
 

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