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  1. #1

    Default Can someone tell me whats going on with the heater core?

  2. #2


    Its just got the hoses all plugged with bolts and Im not sure whats going on there.

  3. #3


    looks like someone cut the hoses off. You'll need to replace the hoses to the heater core to have heat

  4. #4

    Join Date
    Jun 2006
    River Ridge Louisiana-4 miles W of New Orleans-didn't flood-water stopped 800 yards away.


    The PO must have bypassed the heater core because it leaked.
    The leaking is a pure guess, but I can't think of a good reason to bypass it other than a leak ( where is it from-a cold climate or a warm climate).Of course the leak could have been in a hose, but most folks would just replace a hose-maybe not an entire core-big PITA to replace a core.

    1998 suburban-
    1/2 ton

    199500 miles

  5. #5


    My friend is looking at it. Its in a cold climate for the most time haha. Like canada hahaha. But its in a s10 so do you think maybe the hoses were cut when the 350 was swapped?

  6. #6


    Before connecting the system back together I'd pressure test the heater core.
    It could be disconnected because of the 350 transplant, but the heater core would help circulate anti freeze and help keep the engine running cooler.
    350 swaps are notorous for overheating, this is usually because most times they dont upgrade the radiator at the same time.

  7. #7

    Join Date
    Jun 2006
    River Ridge Louisiana-4 miles W of New Orleans-didn't flood-water stopped 800 yards away.


    Yeah, tbplus10 is probably dead on.I had no idea it was a 350 swap. The PO probably just wanted to get the swap done, so he didn't fool around trying to get the old hoses to fit.He just cut them.

    Canada-whooooo-cold climate. You need that heater!!
    I would do just what tbplus10 suggests-don't just hook it back up without testing it first-might end up with coolant all over the freakin place.

    On to a more important subject-HOW FAST IS IT?? Claimed HP of the transplant?

  8. #8


    If it was equipped w/ A/C then changing the heater core is a major PITA. It would only take 1 longer heater hose to hook the S-10 setup to the 350 as the one hose already came out to the thermostat area. I'd bet the core is bad.

    W/ out A/C you only have to remove the radio & glove box and loosen the right side of the dash.
    there is still one cover bolt that is almost impossible to get out; I left it out on my old S-10...

    W/ A/C you have to unhook the whole dash to get the larger cover out. The good thing about that is you can then reach all the cover screws...

    First time took me 5 hours [no A/C] but the 2nd time was only 2 hours...
    Still Loyal to GM after all these years...:shocked:
    2006 Impala LT 3.5L
    2005 Silverado WT small cab/longbed 4x4 4.3L V6
    1999 Grand Am 3.4L in TX w/ our youngest
    1993 GMC Jimmy 4.3L 4 door 4x4 'Ole Rusty' - 'SOLD'
    1988 S-10 small cab/longbed HT3.4L Crate Engine
    1970 Nova 250 I-6, factory 3 sp floor shifter.
    1968 Chevelle 'Nomad' Wagon 250 I-6 w/ 3 on da' tree.

  9. #9


    my guess is that they replaced the engine and wanted to do a quick test to make sure everything was running right, with the intention of going back and hooking it up later and didn't...maybe it was just a summer rat. I agree, do a pressure test of the heater core and hook it back up.

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