[JASTECH]

First of all I would like to say Howdy! I have not been on in a while do to pain issues and Dr's ect. But anyways. The family and I decided to take the F350 to get some straw for the dogs and a bit of shopping. The weather outside is cold at about 20-30 degrees F. After the truck finally started I let it warm up then we hoped in for the 15 mile trip to town. We could see our breath in the cab (after brushing our teeth) so I turned on the heater, well all we got was cold air! And I mean cold! So I looked at the idiot temp gauge and it was on N then the thermostat would open and it would drop down. Well that told me the stat was working. On our way home I repeated everything and still nothing but cold air. After we were home and the F350 cooled down I checked the radiator level and it was under teh spout but over the core so there was enough to circulate. It has a New Water pump, Heater Core and Thermostat. The radiator has been flushed and filled with CAT coolant. Any thoughts would be nice, we are getting real cold out this way like 40 degrees in the living room each morning.
P.S. I left the flush kit installed

Thanks, JASTECH

 

[M.L.S.C.]

If heater core checks out OK (feel both hoses to it, both should be nice and hot) I'd blame your blend door for the issue - Gina over at OBN seems to have the same issue, I promised I'll crawls under my dash and try to figure it out for her, I'll let you know what I find out since your '88 likely has the same setup as our '90s.

 

[JASTECH]

Thanks, that will help a lot. I can't do much crawling under the truck or working on it due to my disability so I hope you find something that I can do.

Thanks, JASTECH

 

[cdnsarguy]

When you adjust the temp switch can you hear a door slam open or closed.... Check behind the glove box is there a red and white bullet and cable lock. If there is ensure the bullet is locked by the cable lock..... IIRC pulling the white cable lock forward at the top GENTLY BUT FIRMLY try locking the bullet with only one red ring showing on the left end.

Other than that fill the rad coolant up and the overflow, ensure the heater is bleed too.

See my 7.3 coolant hose info on the photo link.......

 

[Bill1013]

If heater core checks out OK (feel both hoses to it, both should be nice and hot) I'd blame your blend door for the issue - Gina over at OBN seems to have the same issue, I promised I'll crawls under my dash and try to figure it out for her, I'll let you know what I find out since your '88 likely has the same setup as our '90s.

If both lines are not hot/warm, you may have a valve in the heater hose line, cable operated.

When you shift from -- like defrosters to floor heat is there a difference in air flow ? If not the vacuum line on or to the control may be broken . Also check the vacuum line and motor under the hood, mounted on the passengers side by the firewall, have someone shift the heater control with engine running and see if the vac motor operates. . Sounds like you have a vacuum problem somewhere . The temperature control (lever) is cable operated, and may be broke or disconnected. You have to remove the glove box lining to see the temp.control cable and door. When you move the temp. control does it feel some resistance, move the lever quickly from cold to hot, you may hear the door opening and closing.

 

[JASTECH]

I will go out and check cable as I can do that. It is very cold and windy out here now. BRB

Thanks, JASTECH

 

[JASTECH]

Ok, I was able to get under the dash a little and when I moved the lever for Panel, Floor ect. it could hear it moving something under there and resistance was felt on the lever. I then looked under the area behind the glove box with a flash light and I could see the squirrel cage fan so I reached up to the open/close for inside/outside air and went to move it and felt no resistance at all and could still see the squirrel cage then while I was looking at the squirrel cage the wind blew and the little door was shut then open repeating while the wind was blowing.

Thanks, JASTECH

 

[M.L.S.C.]

Jastech, if you open your hood in the very corner of the engine bay right on top of the squirrel cage assembly there is a vacuum servo, that's the one that controls the inside/outside air door, see if you can move the lever from there.

 

[JASTECH]

I will try that in the morning, I fell out of the truck so hurt my left side a little.

Thanks, JASTECH

 

[M.L.S.C.]

That's why I love running boards, much lower chance of slipping off than the plastic doorsill pieces you otherwise gotta step on when you got in the cab.

 

[JASTECH]

M.L.S.C., I can move the lever on that vacuum pump just fine. I don't understand the relevance due to the flap/door was opening and closing with the wind. So I am thinking that what ever is connected to the door is off or broke? Just a thought as I don't know much about these trucks.

Thanks, JASTECH

 

[M.L.S.C.]

If the recirculating door is moving with the wind then you got broken linkage indeed. What bugs me is that the recirculating door don't determine hot/cold, all it does is shut off the fresh air for max efficiency of the A/C. The temperature is controlled by the blend door, which is actuated by that cable in the picture Bill posted - what's the situation with that cable in your truck?

 

[JASTECH]

So that square that is in the picture on left side is where I was looking and could see the squirrel cage? I want to make sure I am thinking correctly before I go back out in the cold. Let me know and I will go out again. That picture is a little different then mine. My Temp. lever is on the bottom.

Thanks, JASTECH

 

[Bill1013]

JASTECH: So sorry about your fall. I'm 80 and have to slid out of the truck .
That drawing is from an 89 Ford manual, but the air blend door is controlled in much the same way.
The door that was flapping in the wind, is the door that controls air from the outside . The outside air comes from openings (Grill) across the hood next to the windshield .
You said the temp. was 20-30 deg. , driveing down the road could put enough air pressure on that door to hold it open, forceing more cold air in than the heater can put out .
Pull the glove box out and have someone watch that door while you actuate the vacuum motor under the hood, DOES IT MOVE INCONJUNCTION WITH ACTUATING THE MOTOR ? I suspect that door has come unhooked from the motor .

You still have not said wether both hoses to the heater core are hot.

Can you get any heat at all while standing still ?

Are the hoses hooked to the heater core correctly, inside hose directly from the water pump, outside hose to the engine block .

Did you replace the hoses when core was changed ? Internally Collasped hose ?
Pipe nipple into engine block plugged or partially ? Reduced coolant flow.

Heater core may be air bound. Did you bleed it when changing the core ?

Where are you located ? Some TDS member may be close that could help you ?
Pic below may help. Click on the pic when it shows up, then click on full screen for better view.

 

[JASTECH]

Sorry I didn't reply, I had to go to the Dr's again and he changed my meds sense my condition will be lifetime and he stopped one of my pain meds cold turkey and my body is having problems with it so I don't feel to good right now. I will have to lay low for a while until I feel better. When the weather isn't as cold and the wind stops blowing 24/7 I will try and test it like you say.

Thanks, JASTECH

 

[WhiteGardens]

Ya, Let us know where your located. Somebody has got to be nearby to help.

 

[JASTECH]

Western side of Nebraska close to Scottsbluff. Sorry it took so long, my memory issues are pretty bad too and they just put me on the pain patch and percocet, Lyrica ect. still trying to get control of the pain.

P.S. Hi Chuck!!!

Thanks, JASTECH

 

[JASTECH]

chuckster, Longtime no hear! I still need to fix this inside/outside air flap/door. I am on new Pain medications including the pain patch and still no peace in site. Anyways how do I access this door? I don't think anybody lives close enough to me so I will try this with the members help. I also need to need to get that line and cap kit? As the F350 is taking too much time to start so must be air leaks as mentioned. I also am thinking about replacing the mechanical fuel pump with electric. What one would you recommend?

TIA, JASTECH

 

[chuckster57]

chuckster, Longtime no hear! I still need to fix this inside/outside air flap/door. I am on new Pain medications including the pain patch and still no peace in site. Anyways how do I access this door? I don't think anybody lives close enough to me so I will try this with the members help. I also need to need to get that line and cap kit? As the F350 is taking too much time to start so must be air leaks as mentioned. I also am thinking about replacing the mechanical fuel pump with electric. What one would you recommend?

TIA, JASTECH

JAS...Sorry about that..Lots of little issues around here... I have your Phone # and I will give you call in the AM. I will try to talk you through it. Wish I was there to do it for you..talk to you in the am..