Scorpio heater core replacement

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PeterP11c
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Re: Scorpio heater core replacement

Post by PeterP11c » Wed Jun 10, 2020 11:47 am

Well, I follow the instructions as per Shop Manual 36-74-11. These plastic ducts were covering access to the mounting screws. No, I didn't remove the vents, only the plastic ducts for access. As you said, in order to slide out the core, the box itself must be moved forward to clear core plastic hoses out of the firewall. The core itself and those 2 Phillips screws are now visible and I will proceed accordingly. I haven't done this job before, so I go slow and plan every move. Being a sideshow to my daytime job, the progress may not be spectacular. Unless, I am doing something totally wrong, these steps were necessary to properly remove the heater core.

PeterP11c
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Re: Scorpio heater core replacement

Post by PeterP11c » Sat Jun 13, 2020 3:52 pm

Progress report:
Today, is the day of days. After a couple of hours of work, I was able to remove the old heater core from the assembly box. There were a few moments from hell, like short rubber hoses connecting core to the water valve. I had to unscrew the distributor cap in order to get some access for a screwdriver. So, I got out. Next week, I will test both cores for pressure to be sure the new one works and to find out where to old one leaks. That's all for now, time for some relaxation.

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Bob Weir
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Re: Scorpio heater core replacement

Post by Bob Weir » Sun Jun 14, 2020 12:10 pm

Congrats on the progress. :cheers

I'm facing a lawn mower that decided it doesn't want to start anymore and my 2000 Sable Wgn has a CEL from Evaporative emissions circuit fault. :(

I finished upgrading my wife's Mac today. Maybe I should quit while I'm ahead.

PeterP11c
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Re: Scorpio heater core replacement

Post by PeterP11c » Sun Jun 14, 2020 1:39 pm

Thank you, Bob. Appreciate it. Needless to say, that if not for extensive research done online, studying the Manual and yours and other members advice, I wouldn't do it. The work required to gain access was laborious enough. During the process, I discovered many upper and lower dash elements either broken due to sloppy mechanic's work or in need of repair for wear and tear. Found one electrical wire with two connectors unplugged and wonder where they belong. There is a lamp inside the glove compartment but don't see any wiring leading to it. Also, need to restore the plastic end of shift gear selector frame where it meets the lower dash. Broken end piece. The short rubber hoses leading to the heater core from the water valve seemed intact, no torn edges or worn rubber. Will replace the metal clams with better ones, as these gave me a hard time to unscrew. Much work ahead, but must gratefully acknowledge the heater core slid out of the box like you said and brought a big smile to my face.

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Bob Weir
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Re: Scorpio heater core replacement

Post by Bob Weir » Sun Jun 14, 2020 2:04 pm

I know you're a glutton for punishment, so include a few other items for your frustration.
1] Vent motors at driver's foot. The plastic gears strip sometimes when the vents get stuck. Boss gears available and easy to instal on motors, but frustrating to align. I've never had to do it, but others have.

2] Fan motor controller. I forget the proper name and acronym, but it's sitting on top of the photo I provided. I have a write up on how to test and a replacement if you need it.

3] U wrote: "Found one electrical wire with two connectors unplugged and wonder where they belong. There is a lamp inside the glove compartment but don't see any wiring leading to it."
Luv to help u more, but I don't have any of my 5 Scorpios any more. I can email you piks of wiring diagram from Elec Vac & Vac Book .

Don't forget MCA sponsors for parts. These guys are really good to us Merkur crazies.

Call me anytime 610-248-1481 Leave message if I din't answer.

PeterP11c
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Re: Scorpio heater core replacement

Post by PeterP11c » Sat Jun 20, 2020 10:51 pm

Gentlemen,
I am pleased to announce that my new heater core is in. It took me 5 hours to do the job. Started nice and easy, two Phillips screws to fasten the core inside box, but trouble began with making it all fall back in the original setting. I pushed and twisted gently mindful not to break the plastic hoses and finally it went in. Putting the #13 holding nuts was easy on the right side, less so on the left. The real headache began with connecting rubber hoses to plastic ones and tightening the clams. There is virtually no room to maneuver and I put both clams to the right. Big mistake!. Started the engine and it all leaked like a sieve. Well, either the new core was bad and/or my rubber hoses were shot. Drained the coolant and pulled rubber hoses from the core, then did a rig installation of the old core just sitting on the fire wall. Kept the clams very tight and restarted the car. No leak. OK. Dismantled the temporary rig and put the rubber hoses back in. Obviously the leak came from loose clams. Tried to do it with a socket wrench and a screwdriver but both clams were there but not tight enough. Decided to take the battery out and shifted both clams in opposite direction. First, did the lower hose, first with #8 socket and short extension but no wrench. Once I got a better fit, then finished the job with flat wrench. Repeated the same with upper hose, making sure the clam was real tight. Installed battery back, filled the coolant and started the engine. Bingo. No leak, all dry and working. 5 hours of PE. No need to go to a gym. So, for posterity and others who may face a heater core job: put the clams on the left, under the water valve. You will be able to see them and ensure a proper fit. Not sure, if that was an original OEM solution but it does make sense.
Now, some rest and relaxation before next phase, putting lower and upper dashes back. Will keep you posted. :D

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