Heater Core how to

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Grit dog

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Wanted to thank @SirRobyn0 for the very detailed write up.
I managed a couple hours yesterday with “nothing to do” (on Xmas nonetheless lol) and removed the heater core out of the 86.
The pics and instructions were AWESOME!

One minor note, the “2 bolts” on the inside that need to come out. One on the far right and the other is the middle of the truck, hooking the big heater ac box to another plastic plenum.
Can get to the bolt straight thru under the ash tray.
 

SirRobyn0

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@Grit dog Your welcome. Thanks, feedback like that is the only way I know if anyone has found it useful. Glad it went well for you, how much time do you think you have into it? and how many beers or shots of whiskey would you rate the job?
 

Grit dog

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@Grit dog Your welcome. Thanks, feedback like that is the only way I know if anyone has found it useful. Glad it went well for you, how much time do you think you have into it? and how many beers or shots of whiskey would you rate the job?
It was invaluable.
I’d rate it more than a 2 beer job, lol.
I have 1.5-2 hrs into removing it and replacing the core.
But the 2 halves aren’t lining up quite right. I think the new core is holding it from lining up. So I’ll need to fiddle with that.
I’d call it a half day job, idk won’t have time to finish it up here til maybe end of the week.
I’m sure you’re way quicker, hell you took pics along the way and it was only a 2 beer job for you!
 

sidschev

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future reference rockauto usually has the right parts.......and you can see what your buying also returns are easy
 

Soundmound

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It was invaluable.
I’d rate it more than a 2 beer job, lol.
I have 1.5-2 hrs into removing it and replacing the core.
But the 2 halves aren’t lining up quite right. I think the new core is holding it from lining up. So I’ll need to fiddle with that.
I’d call it a half day job, idk won’t have time to finish it up here til maybe end of the week.
I’m sure you’re way quicker, hell you took pics along the way and it was only a 2 beer job for you!
Had the same issue with the case. It was the aftermarket aluminum core for me. Ordered a brass unit from summitracing.com and it slipped back together silky smooth.
 

SirRobyn0

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future reference rockauto usually has the right parts.......and you can see what your buying also returns are easy
I have a VERY different experience with rockauto and lost $500 on a defect ECM I returned. For that reason I will never use them again. But we all have different experiences.
 

SirRobyn0

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It was invaluable.
I’d rate it more than a 2 beer job, lol.
I have 1.5-2 hrs into removing it and replacing the core.
But the 2 halves aren’t lining up quite right. I think the new core is holding it from lining up. So I’ll need to fiddle with that.
I’d call it a half day job, idk won’t have time to finish it up here til maybe end of the week.
I’m sure you’re way quicker, hell you took pics along the way and it was only a 2 beer job for you!
My core didn't line up perfectly either, but a little fiddling with it did the trick for me.
 

Grit dog

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Had the same issue with the case. It was the aftermarket aluminum core for me. Ordered a brass unit from summitracing.com and it slipped back together silky smooth.
Well, between you and Rob, more valuable info. That’s what I figured, just hadn’t confirmed yet.
Good to know Summit has an OE style. Just in the last couple years started buying parts from Summit and have had good luck/quick shipping.
Gosh I hate turning simple stuff like this into a project. Seems to happen with car parts more often than not though. Even newer vehicles.
I feel the more Chinesium, the more issues. Maybe I have selective memory but I don’t recall this say 25-30 years ago when Napa was quality (where I got the core) and local parts stores still existed.
Oh well, gone for 3 days again so figure it out later.
 

Soundmound

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Well, between you and Rob, more valuable info. That’s what I figured, just hadn’t confirmed yet.
Good to know Summit has an OE style. Just in the last couple years started buying parts from Summit and have had good luck/quick shipping.
Gosh I hate turning simple stuff like this into a project. Seems to happen with car parts more often than not though. Even newer vehicles.
I feel the more Chinesium, the more issues. Maybe I have selective memory but I don’t recall this say 25-30 years ago when Napa was quality (where I got the core) and local parts stores still existed.
Oh well, gone for 3 days again so figure it out later.
Don't feel bad. I spread the job over two weeks and had it in and out no less than 3 times. Partly due to needing additional parts and needing to verify the replacements worked, partially to do over some seals I wasn't happy with. Now, I know I can do it almost blindfolded and have the security of knowing it's done right and should last years to come.
 

Trucksareforwork

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Helpful write up sir Robyn.

I did my 85 today. It had started leaking back in December after a long highway drive.

Took me about 2.5 hours of actual work not counting breaks.

Biggest surprise was the amount of disassembly required on the heater box.

The under hood work wasn’t all that challenging. I used a taped wobbly on a deep socket to get at the lower outside studs.

I used the summit racing brass copper unit. Seemed to be a good fit.

Road test was successful.

Thanks for writing it up.
 

SirRobyn0

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Helpful write up sir Robyn.

I did my 85 today. It had started leaking back in December after a long highway drive.

Took me about 2.5 hours of actual work not counting breaks.

Biggest surprise was the amount of disassembly required on the heater box.

The under hood work wasn’t all that challenging. I used a taped wobbly on a deep socket to get at the lower outside studs.

I used the summit racing brass copper unit. Seemed to be a good fit.

Road test was successful.

Thanks for writing it up.
Your welcome. I used the standard parts store aluminum unit, which didn't fit great, but I was able to make it work. Had I know about the summit racing unit I might have gone that route, seems like ya'll have had good luck with it.
 

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