Hi to everyone out there.
I have a 69 Mach 1 Marti report 351 4v optioned with Air con. power steering, disc brakes all the spoilers optioned with a 4 speed wide ratio now running a 5speed tremec.
Heater Core with Air Con
Now I have read many comments about Heater boxes, core replacements etc so here goes... I've done it...My heater core hoses were sealed off implyiong a leaky core so okay, replace it.
Step one. You need to get the gas out of the air con system first then disconnect the hoses in the engine bay. In the Cabib you have to take the top of dash out, the clock facia and dash cluster out, the radio out, the heater control mechanism out, the bottom off the dash, black metal out and then undo a nut in engine bay and one in cabin near you that hold the heater box, disconnect associated cables 2 off, and it will slide out.
Being air con its bloody heavy as it has the air con unit , ?? evaporator thingie in there as well.
The unit is made of fibreglass so be gentle. the clips are easy to remove flat screw driver in bend of clip and pry out.. there are 12 and some are near fire Wall
so you cannot do this without complete removal.
Things the buy Heater core Brass recommended, foam filter kit, adjustable thermostat new globes for dash 5W spade type and new globes for clock .
Split the heater box remove all the slide out parts ie the swivel control pieces and the heater core. clean it all and lubricate swivel parts and silicone on all new foam parts , The kit comes with a schematic were to place me picture all great.
I must point out that BEFORE you remove heater box there is a drain through firewall its located under heater box be careful as easy to break.. this drain is to drain excess condensation from air con to ground through firewall you know car sits with air con running a puddle under it a good sign its working and not blocked.
After all cleaned new core replaced degassed etc and with car running about 2000rpm watch the air con temp drop.. put a temp probe in centre vent doors shut it should drop to say 5.5 C and air con cuts out then cuts back in at around 6 C this is so the unit will not freeze up I installed a adjustable thermostat on mine which is accessable with glove box installed but remove side screw and it drops free..
So I adjusted mine to freeze down to 5.5 cut out temp rises to 6C then cuts back in.
It is a major job probably bigger than engine removal.. but I hate things not working and as for originality well after 50 years any original car's FOAM would be cactus..
any questions please ask... I have also fitted a retro radio GRRRRRRRRRRRRRRRRRRRRRRR
will write about that soon, upgraded the headlights to look standard. Fun...Oh and for those with OLD cars that have had No master Cylinder work REMOVE It and get it checked. Mine had corrosion a piece came loose and blocked the return pressure line locking the brakes on.. another story to follow but now all good.
So to conclude.. If you have AIR CON you need to remove just about all the dash .. without air maybe just the top and the glove box a sit is a lot smaller.
By for now 69FORD John