OK...So yesterday I purchased a 65 fastback with a 289. It started right up and ran fairly well every time I went to go look at this thing. So last night I got the car home, started her up and let her run for 15 or 20 minutes. Well after about 10 minutes the pressure release valve on the radiator cap began shooting fluid and fluid shot up from under the cowl. So I turned her off and then noticed a good amount of radiator fluid dripping from under the dash on the passengers side of the car. I havent had a chance to start taking things apart due to my job but I plan on getting into it this week after work. I am thinking it is the heater core but I am not entirely certain. Any thoughts on this issue would be great!

 

Most likely the heater core blew. But also check out the entire cooling system. Better to fix it all at once.

 

my heater core was leaking but it didnt blow i had the same problem also if you drive the car around sit it then get a ton of leakage after sitting its definitly the core check your hoses too though

 

to check, one way (easiest i think) it to bypass it al together, take one of the hoses that goes into the firewall, leave it connected to the motor, THEN take the other hose and disconnect it from the engine, then re attach the one that is still on the engine, and attach it to the place where the other one went in.
basicly, it makes a circle, and in that circle is the engine, hoses and heater core, and you need to bypass the heatercore

i feel like that made no sence, if it didnt tell me and ill try to re do it
good luck!

 

Cool...thanks for the input guys. I ordered a new heater rebuild kit online, might as well rebuild everything. Any idea what a job it is going to be to pull the heater core. Never done it before.

 

i havent done it, but i get to do it to a cavalier over before winter so we have heat haha. i heard that they suck to do :/

 

do you have any more pics of the car? im curious to see what it looks like in that color! looks good in that one though!

 

Just did the heater core on my 68. Its not too bad a job other than standing on your head. On a 68 you pull the whole heater box out with the core in it. I cleaned up, regasketed and painted the box while it was out. I dont know if a 65 is setup the same way or not/ Check out this link before you start.

http://www.mustangmonthly.com/howto/5769/index.html

 

bypass your heater core for the time being, by running the heater hose directly in and out of the water pump instead of running it to the firewall, plus it will let you check out the cooling system. That will provide you time, still let you drive the car, until you can pull the heater core. Just take your time, especially when you start breaking down the fiberglass box once it's out. The fiberglass is fairly brittle after 40 years. You might be better off cutting the clips off, and replacing them, rather then force them off which usually shatters the fiberglass. A new box is about $75.

 

Yeah I still haven't taken to many pictures of the car yet...I literally just got it two days ago and haven't had the time to do it yet (work/no sunlight). This afternoon I should be able to and I will get them posted. I def will try and bypass the heater core for now until the new parts come in. That way i can get her started and on the road. First things first...Title/Registration and insurance! That way I can legally drive her.