Heater core interchangeability?

Howdy gents.  Farm Truck, our 89 Bricky with a new used 7.3, does not provide much heat. We've flushed the core both ways, not gotten much our. Hoses aren't the problem. Recently we installed a Wix coolant filtration system. No change, still weak heater action, the ladies complain.

So here I am considering our row of parts trucks ... wondering if all the OBS heater cores, 1980-1997, are interchangeable. The cost of parts having gone nuts, my 2018 decision to buy parts trucks is paying off. I know dashboards were changed from Bully to Bricky to Aeronose, but did the heater cores also change?

Non-Bully side remark:
We have 3 Gen 1.0 SDs (99-08) with heater cores that are 20+ years old, no issues. But at work my oldest sees a lot of gen 1.2 heater cores fail within 10 years. That would roughly the 6.4 restyle, whenever the SD got that snazzy new dashboard. Well, apparently Furd also cheaped out on the heater core. Fortunately, the new dash is easier to pull. FYI

Heater core is interchangeble on AC models 1980-1997, non AC 1980-86 the system is entirely different. Bricknose non-AC may interchange as those use a fresh air vent system that is AC inside ducting and underhood lacks the AC casing.

Wondering if perhaps your problem is not the heater core but rather the blend door.

When you take off the dash to replace the heater core, you can check the blend door. I bet you it's busted. JBG is selling them at 50% off right now.

Also, seems like the only thing that could fail on the heater core, assuming it's not leaking, is that it is clogged up and not allowing enough/any flow. Why not just pull your hoses and flush it and see what kind of throughput you get?

Littlebeefy wrote

When you take off the dash to replace the heater core, you can check the blend door. I bet you it's busted. JBG is selling them at 50% off right now.

Also, seems like the only thing that could fail on the heater core, assuming it's not leaking, is that it is clogged up and not allowing enough/any flow. Why not just pull your hoses and flush it and see what kind of throughput you get?

What's JBG?  

Yes, that's a good plan for the blend door, thank you.  And yes we did flush it, both ways. Flow was fine.  I'm thinking the blend door is the culprit here.

JBG is Jeff’s Bronco Graveyard.

https://broncograveyard.com/

anyone maintaining or building a bullnose needs to know "jbg ". for reference if nothing else. great source of parts and info. sometimes parts not available anywhere else.

mat in tn wrote

anyone maintaining or building a bullnose needs to know "jbg ". for reference if nothing else. great source of parts and info. sometimes parts not available anywhere else.

Yes I have used them in the past with satisfaction. They also answer the phone, a rarity. Try calling Flaming River sometime, on the other hand. Grumpy folks.

As to the JBG acronym, IDK.

Just thinking but if the door is the issue I would think one way to check before pulling everything apart would be are both heater hoses hot?

If both are hot then I would guess heat is not being pulled out of the water through the core.
You did say you flushed the core both ways and that was good.
So if you have flow and the hoses are both hot then a guess the door could be the issue.
Dave ----