Heater Core Question

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Oct 30, 2010 | 06:22 PM

Old Brown F250

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Heater Core Question

I'm replacing all the heater hoses under the hood and was wondering about the heater core.
Am I right in assuming the two tube ends sticking out of the firewall are coming directly from the heater core?

1972 Ford F250, 390 V8

Thanks in advance.

Oct 30, 2010 | 06:57 PM

sandmanf250

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heater core

if you install them backwards,it will not make any difference.it is called back flushing if you reverse the hoses,but you will still get heat either way.if it ever starts not heating good,reverse the hoses and it'll usually start heating again.it's kinda like a free flush job.

Oct 31, 2010 | 09:29 AM

Victor L

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You are right that the two copper tubes 'are' the heater core tubes.
Replacing the core should allow your heater to work to its full potential, but swapping the hoses for the reverse flush might do the trick, as long as it isn't leaking.
Dont forget, the thermostat under the upper radiator hose allows your heater to warm up faster, and controls the temperature of the coolant.

Oct 31, 2010 | 10:08 AM

Old Brown F250

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Thanks for the replies.

Originally I was just going to replace the coolant temp sender in the top of the intake, the old one had high resistance. But with most of the coolant drained I went ahead and changed the thermostat and the smaller heater hoses. The two main radiator hoses are still soft. One of the 'ears' on the thermostat housing broke off so I had to get a new one.

There is one short section of heater hose between the back of the water pump and the block that I would like to change. But to do the job it looks like you would have to remove the belts, fan, alternator, power steering pump, both front brackets and then the water pump just to change that short hose. I wait till it starts leaking or the water pump needs changed.

Oct 31, 2010 | 03:12 PM

CougarJohn

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Joined: May 2001

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From: Cupertino

I change hoses and belts every five years or so. When I do, I hake a garden hose with a sharp schnozzle on the end, jam it into one if the heater hoses and clamp it, and turn on the schnozzle. It blasts crud out of the core.
One of the problems with reversing the hoses to back flush, it seems to me, that the crud coming out ends up in the radiator.
I am glad you got your problem solved and that the guys helped you.

Oct 31, 2010 | 04:17 PM

NumberDummy

Ford Parts Specialist

Joined: Nov 2006

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From: Simi Valley, CA

The by pass hose (between the water pump and the manifold) is the same diameter as the heater hoses = 5/8"

Be prepared if you have to replace it. The by pass hose clamps onto a 5/8" nipple that is pressed into the intake manifold.

When you remove the old hose, part of the nipple may come along with it, as it may be rusted out.

Autoparts stores sell a replacement, but it may be too long, so will be "cut to fit."

btw: The heater water valve (splices into the intake to heater core heater hose) is still available from Ford.

C3UZ18495A .. Heater Water Valve (Motorcraft YG133) / Fits: 1965/66 F100/1100 / 1967/72 F100/750 / 1963/74 Econoline.

Nov 2, 2010 | 06:43 PM

baitmaster

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From: nevada

I have replace my hoses a few times over the yrs, and have never found a replacement bypass hose. My trick is to cut the old one in half, slice both halves lengthwise, and pull off. If the metal is still good, I just clean it up. To put a new hose on, I cut a short piece of 5/8 hose, just a hair shorter than the orig, and soak it in a pan of very hot water. This softens up the rubber enabling you to squeeze it a bit and get both ends on. Always works for me. I also always keep the old hoses (radiator) in the toolbox just in case. And a piece of 5/8 new heater hose too.