I have a 1974 valiant w/ a 225. It's my daily driver and I am having some seroius overheating problems. The temp gague will read over last mark in about 20 min run time. Smoke has come billowing from underneath hood many times and when i shut her off, she chuggs like she still wants to keep on runnin. I have had a new radiator cap put on and a new t-stat about 5 mo. ago. What do you suggest to fix this?
The latest problem to be added is oil spatter. I had driven about 30min to work and my laptop was on the passenger side floor. When I went to pick it up there was oil spatter all over it from somewhere what is causing that? is it related to the overheating?

Anybody and everybody's help is greatly appreciated, I have no where else to turn- Bryan

It might be two different things, but...

If you have some 'coolant' leaking out from under the dash onto your laptop, you might have a tanked heater core that needs to be replaced (this can cause some overheating issues)... does your exhaust have white 'smoke' coming out of the tail pipe? (if so that's a head gasket issue...)

You can pull your heater hoses and 'bypass' them(connect them with a peice of pipe and hose clamps, or make a 'loop' from one outlet to the other inlet) to see if that solves the problem (if so, you need to order a new heater core and replace it in the heater box...)....

If not, we'll be here to help...

-D.Idiot

is the heaterbox black and located by the passengers feet(if they were in the car)? if so, then how would I replace it??

You'll need to check with your local parts stores as most A-body heater cores are available, but a 24 hour 'wait' from the local warehouse...


You have to open up the vent door and locate the 3/8" nut and loosen so you can 'unhook' the 'j' hook off the cowl lip.
Under the hood, locate your heater hoses and remove (you may need new ones if they are petrified and you have to cut them),
then locate the black heater motor on the fire wall, it should have 3 - 1/2" nuts holding it to the wall, pull the nuts (save all fasteners in some container for reinstallation). You may also have a plate and screw by the heater core inlet/outlet on the firewall, remove this too...

Back under the dash, locate the heat control cables and firmly pull them out of their retaining clips on the box. Put towel on passenger side floor if core is tanked and leaking. Pull heater hoses off the box.

roll unit out of the firewall, and from under the dash and take to your work bench/garage floor. note where everything goes (fasteners), since you'll have some parts to put back later...

Pull the inlet/outlet bezel (plate with two holes in it, and the phillips screw),
There will also be a ground wire to the blower motor, make sure to remove the screw and let the wire hang loose. Look around the edges you'll find some 'clips' holding the box together , use a screwdriver in the outer 'slots' to pop them off. pull box apart, careful not to lose the doors in the box. Replace heater core. Wipe box out with a clean rag. If the diverter doors have some nasty fragile foam, remove from doors, and replace with closed cell foam tape from you local hardware store (this will help seal the doors better so you get positive pressure for defrosting, etc...).

Reassemble in reverse of how you disassembled it, and reinstall. Exception: Check to make sure the control cables are installed correctly (i.e. install and move the controls and see if they open and close the doors properly).



If you have an A/C box, this proceedure won't help you as it's completely different for that monster...

if not confident about how to do this proceedure, check with your local mechanic with a good reputation.

-D.Idiot

Thanks, I will try this as soon as the weekend Hits!!!!!!