I guess my heater valve is out and my shark is trying to cook me alive
I just drove about 20mi to go pick-up my GrandPrix tickets and on the way back I started Cookin.
Question ?? If your handy with a wrench how long does it take to replace the heater core valve? Anyone? I would have to do it tonight cuz The grand prix thing has to happen and Im not goin in the Ford.

 

30 minutes.
Pop off the air filter top and base.
It's right there near the fuel pressure regulator on the passenger side at the rear of the motor.

Before you replace it, check that it is getting vacuum and closes (arm pulls back) when you start the motor. If not, you can temporarily wire it shut. Here is Tony's way of doing it. You only need to do step 1.
http://members.rennlist.com/v1uhoh/summer.htm

Also, these valves can fail internally, so that even if the arm moves, the guillotine style valve does not hold back the hot water. In that case, you would need to replace the valve. There is a NAPA supposedly all metal (inside as well as outside) replacement, but I just use the stock valve as they seem to last 15+ years.

If you replace it, you will lose a fair amount of coolant. So have a gallon handy and refill the reservoir with a 50/50 mix while running the motor until it gets fully warmed up and with the heater on.

The short hose from the block to the valve is a WYAIT item. It's odd size, so you will need to get that from one of our favorite vendors.

 

thanks for the reminder. mines works intermittently, sometimes its fine, and other times its pumpin heat when you dont want it. now i have my next project.

i also assume it is NOT normal for air to always be coming through the front defroster vents, even when all of the vents are closed in the via the front register control and the fan set to zero.

 

If the valve is not closing with motor and air on you can route the vacuume line ahead of the one way valve located near the brake booster. Use a T and vac hose works fine as a patch. If you connect it ahead of the valve off of the booster every time you get on the car the vacume will drop and you will get hot air.

 

Yeah, you probably have some vacuum problems. That can be at the source or at the actuators that control the air distribution flaps or inbetween. Start at the 4-way connector near the brake booster and work your way to the actuators. There is a line off the 4-way that provides vacuum to the cabin. That goes to a vacuum manifold/solenoid device that is mounted behind the radio. It is held in by 3 screws. The center one can be a bit of a bitch - you need a small ratchet that will hold a Phillips bit at 90 degrees. It has a bunch of solenoid controlled valves that go to the actuators. You can test the solenoids and then the downstream lines that go to the actuators. There are diagrams of the vacuum line routing and line colors in the WSM. If the lines going from the manifold to the actuators do not hold vacuum, then you need to examine the actuators. Some are easy to get to. Others require the console to be pulled. It is common for the diaphragm inside the actuator to split. I believe Roger (928srus.com) sells the diaphrams (cheap) or you can just replace the whole actuator (expensive).

Oh, I just remembered John Pirtle's excellent guide on this...
http://members.rennlist.com/pirtle/svc_act.html

And he has a super guide on the heater valve.
http://members.rennlist.com/pirtle/svc_heatv.html

Jeez, I could have saved a lot of typing keystrokes.

 

thanks! the vacuum stuff is all new to me ... will have to dig in and see whats up.

 

I just pulled my console out recently to R&R the interior vac system. The orange line to the comb flap was completely disconnected from the "switching" manifold. That explains why the lower center vent blew all the air and the upper center vent was very low on airflow. Me and my passengers would always fight for the lower center A/C vent. The blue line to the fresh air flap (under blower motor) holds no vacume. This vacume pot is shot, or the line is disconnected. The combination of both of these vacume leaks would not allow anything to work. The hot water valve would not fully close, the fresh air door stayed open allowing in hot outside air, and the center comb flap stayed shut. It is a miracle that I got any cool air at all.

The defroster flap "sticks". It will open with a mighty vac, but it takes several pumps before it will break loose and open up, and then it holds vacume fine. I thought I could hear a hissing noise from behind the pod, but I think it was the orange line that was making the hissing.

 

Thanks bill. You are the man.

 

Mike,
What is up with your avatar? What/Who the hell is that and what are you/he doing?

 

piccardo
If you are in a hurry then just lock the heater valve closed with a cable tie, takes 10 minutes

marton

 

Make sure the new one is installed in the correct orientation.

Many times that valve gets installed backward which causes it to not seal properly when closed.

Look for the arrow on the valve body. Coolant flow is from the engine towards the cabin.

 

John,

The mystery man in the photo is me. I was at the river walk in San Antonio and me, my stepson and his friend all bought these "wrestler" masks. On our way back home, we put them on and my wife snapped the pics.

 

Bill, thanks for those links. I found a vacuum hose was unhooked (right off the Y splitter). hooked it up, all issues resolved ...!

 

That was too easy!

 

yea, i'm just waiting for some bizarre side effects . put 200 miles on her today including a sprint up to 130 .... not a hiccup!