My heater seems to not be working. It's just blowing air into the cab. How do I know if its the heater core or the blower? And or how do I find out what the problem is before i tear into the truck. Thanks fellas!

 

if its blowing like you say than blower is ok.from passenger sidelook at bottom of heater box . find where control cabels attach and make sure the the levers move. other than that the heater core is a small radiator that gets hot like the rad and a fan blows air thru it making heat. are the heater hoses from the motor both warm? is it ac equiped?

 

is the heater box under the hood or in the cab? also it's got an a/c but i think it's aftermarket and its not hooked up to the belts. i'll have to check the heater hoses

 

How do you operate the A/C?

If the switches are separate from the heater control panel, it's not factory integral air.

If the switches are part of the heater control panel, it is factory A/C.

When factory A/C is present, there's a heater water valve spliced into the heater hose that's controlled by vacuum, and is notorious for getting stuck in the closed position.

 

i don't operate the a/c is there is no belt on it and yes the controls are seperate from the stock ones

 

Sometime after it's sat and got cooled off, start it up and feel the heater
hoses and feel if hot water is running through them.

The part "Bill the ND" is talking about froze up on me right after my pickup
went out of warranty. I replaced it with an in-line gate valve. Since then I
replaced it with an engine-mounted ball-valve...

http://www.panix.com/~alvinj/file12/bypass.jpg

I don't know where you are but this winter you -could- just bypass the part
'til spring. ;)

But then it might be it's your heater core itself is plugged up. :/
There's been a couple guys that's found that to be the case in the last
couple months here.

Blowers can sometimes only blow air out the defrost ducts. (vacuum problems)
If it's blowing air out on the floor you're prob'ly ok with that part. :)

Alvin in AZ
ps- the "stealership" wanted close to $40 for that part in the fall of '77
pps- "that's almost 40 dollars with tax :/ I could replace it with a valve
from the hardware store for 2 dollars :(" "go ahead {smirk}" -parts guy
at the stealership in Safford AZ

 

ACH du LIEBER!!

That dealer in Stafford must be one a the in-famous Ben Dover Motors franchises.

D4AZ18495A .. Heater Water Valve (Motorcraft YG136)

MSRP: $28.72 / FTEpartsguy.com price: $17.23.

 

I know i'm gonna sound dumb and all but which hoses are the heater hoses? I'm just starting out at this stuff.

 

http://www.panix.com/~alvinj/file12/bypass.jpg

The hose hooked to the red-handled ball-valve is the heater hose that flows
hot water from the engine to the heater core.

The "other heater hose" hooked to the heater core is the "suction side" of
the heater core.

---------------------------------

The bypass hose on mine is what I took the picture for and wanted to brag
on. :) It's a 5/8" inside diameter A/C hose. LOL :) It's the short hose near
the center with the two hose clamps on it. It's always open and the water
pump is always sucking water through that hose into the pump. The water
flows from the pump into its two-iron-arms that are bolted to the block.

Water is constantly flowing around inside the engine! :)

The thermostat opens just a little when the engine warms up enough and
water starts flowing through it into the top of the radiator and gets sucked
back into the pump through the lower radiator hose.

Theoretically if you remove the thermostat, too much water will flow through
the radiator and not enough water flowing around inside the engine and can
actually cause an over heating problem.

---------------------

A service manual will answer questions that a guy could never even think
of! :) The service manuals aren't big in theory, which is important to real
understanding but the theory part is what you can get plenty of here. :)

It's the fun part to me. :)

Alvin in AZ
ps- Nothing wrong with "young n dumb" as long as you're trying! :)
pps- I was "young n dumb" but one day realized I was now "old n stupid" :/
ppps- So I'm wondering "when's the smart part supposed to happen?" :/

 

Alvin, Did you get your heater working?

 

Yep. LOL :)

Took the original vacuum operated valve out, cleaned the rust out of it and
got it working good, put it back in, but it froze up on me again right away. :/

I scrounged a used gate valve from somewhere and (bought?) an iron pipe
nipple (cut in half) and used that set-up for about 20 years then happened
to notice the wide bodied ball valve at a hardware store (with a large hole)
and installed it. :)

The problem with the dangged gate valve was I couldn't look at it and tell
if it was open or closed. :/ The ball valve kicks butt. :)

That's my story and I'm stickin to it. ;)

Alvin in AZ

 

I posted the info, as you can see, you can buy a new valve (that might last pick one: a day, a week, a year) from FTEpartsguy for $17.23 + shipping from WA to Arid Zone-a.

 

Hey Mr. Bill, I hope you are having a nice Sunday evening.