Heater core on 87 CSX

[iTurbo]

Today I removed the heater and A/C box on my 87 CSX in order to install a new heater core. I'm in the middle of cleaning and overhauling the assembly now. Thankfully there wasn't dead mice in it unlike when I did my 87 SL!

Now, the A/C doesn't work on the car and hasn't in years. I could care less about having functional A/C since I live in northern Wyoming. So it occured to me that I might be able to improve heater performance by removing the evaporator and blocking off the box and firewall where the A/C lines and H-valve were.

Waste of time or worth it? Obviously the heater is very important and I've also considered eliminating the heater control valve and making sure I have a 195' thermostat installed. Since the blower motor has to blow through the thick/dense evaporator it seems like just removing it could really help.

[cordes]

I left mine in when I was in the same situation, but I think if you have the time it may be worth it to remove the evap core. If nothing else you should get much better flow out of the blower motor.

[iTurbo]

Yeah it will be interesting to see how the blower output will be affected.

This morning I got the assembly stripped down to a bare plastic box and brought it to a local car wash to blast the nastiness that accumulated at the bottom. I have it all reassembled now with a new aluminum Vista Pro heater core from Rock Auto. I used all the foam insulating strip it came with, plus a little more similar foam strip I had lying around. I wanted to insulate it really well so all the blower air would have to go thru the heater core and not around it.


Also left the evaporator out and made a block off plate out of some 1/8" plastic and RTV'd into place on the box. I'm going to make a separate block off plate for the firewall after the box is back in. Will report back after everyhing is back together.

[turbovanman²]

As long as the area is sealed where the Evap core used to be, you'll be fine. Some box's use that core to direct air and without it being there, it will cause issues.

[looneytuner]

If you get the Modine core, it is twice as large as stock. You can drive with the windows down in winter. Leave it in. Somebody buying the car is NOT going to want to pull it apart to install what you left out.

[ScottD]

If you get the Modine core, it is twice as large as stock. You can drive with the windows down in winter. Leave it in. Somebody buying the car is NOT going to want to pull it apart to install what you left out.

+1. Unless you plan on dying and being buried in this car, while you're there put the evaporator in. Those of us who like these cars a) are primarily concentrated in the midwest and east coast where you need AC and b) are getting older and want ac. I know my days of not caring if the AC works are done and I'm actually about to remove the dash in my GLHS to put a new evaporator in.

[cordes]

That's some good advice Scott. I should probably follow it, but I've elected to get good at pulling dashboards. I can do my Shadow in no time at all.

[supercrackerbox]

I've pulled more L-body dashboards than I care to remember. One of my least favorite things to do.

I hope the heater core in my Daytona lasts forever.

[iTurbo]

So far I have the HVAC box ready to reinstall back into the car and have sealed up the pass thru for the A/C lines on both the box itself and the firewall. I also removed the h-valve and line assembly so the only thing left is the condenser up front. I will leave that there because I don't want to disturb the airflow thru the radiator by creating large gaps.

I have kept all the stock A/C parts in a box and it wouldn't be that hard to reinstall, even though I'm sure at this point in the car's life many of the components will need to be replaced with new anyhow. I will probably never sell the car and if I really need A/C then I can drive the Caliber.

I will report back when it is running and let you all know how it works. Unfortunately I accidentally broke the temp blend cable and will be attempting to order a new one on Wednesday. I'm still trying to decide if I should eliminate the heater bypass valve too. If so I will just throw it in the box with the A/C parts so it be reverted back to stock someday.

Also not sure why you guys are going so far as to remove the dash just to do the heater core? It wasn't that hard to remove the HVAC box on my CSX as outlined in the FSM. I've done my SL without removing the dash either.

[135sohc]

For the amount of crap you have to unplug/remove/disconnect just to get the dashboard pulled away from the firewall I find it is less aggravating to just take it all the way out and not have to work around it.

[cordes]

For the amount of crap you have to unplug/remove/disconnect just to get the dashboard pulled away from the firewall I find it is less aggravating to just take it all the way out and not have to work around it.

I've done it both ways and I really prefer to pull the whole dash.