74 Crewcab Heater core Question
 

I've been asked to help a friend change the heater core in a 74 CrewCab.Does the box the core is installed in come out the bottom of the dash or is there another way to replace it? This is my first heater core replacement in this body style truck so any help would be greatfull. Thanks:metal:

Re: 74 Crewcab Heater core Question
 

Don't know about crew cabs, but on the three regular cab squares I have owned, all the heater cores came out from the inside. If you can get your hands on a Haynes or Chilton manual it will help. You remove the duct from the inside and the heater core is strapped inside. So, disconnect the heater hoses, catch the coolant in a pan, disconnect wiring, remove nuts from around the blower housing, GENTLY remove the duct from the inside, remove the heater core from the straps and replace with the new heater core, reinstall the duct, connect the heater hoses, top off the coolant, enjoy heat.
Make sure you use a copper heater core - don't get an aluminum one.
If you have A/C on the truck, then you have to "feel" for the nuts under the blower housing because they are not easily visible, and the reinstall is a wiggle this way, wiggle that way affair. I used a mini socket with u-joint attachments and an inspection mirror and a scratch awl to find the holes. If you don't have these, see if you can borrow them. You can buy an inspection mirror for $2-$3 at Harbor Freight - excellent investment.
I stress - do everything gently. The plastic housings can crack easily on these old trucks, and the heater core can leak if you break the solder joints with rough handling. On the bright side, shop labor for this job is about $250, so it is always worth a shot to try it yourself.

Re: 74 Crewcab Heater core Question
 

Take it easy on things, make sure that if it comes with foam in the package to use it with the instal by wrapping it around.

alum. ones suck, I have one and it doens't even compare to the old copper core.

Re: 74 Crewcab Heater core Question
 

Yeah, if the insulation is shot (most likely), then get some foam insulation to match it from the hardware store.

Re: 74 Crewcab Heater core Question
 

Thanks for the replys. The Crewcab was a heat only tuck until somebody put an add on a/c package on it.
Thanks:metal: