the 96 astro van I just picked up has a heat problem.
The thermostat is opening and closing like it should.
the air seems to be putting out cold air.(not really warm engough out side to tell this correctly)
I also noticed the when the stat does open the temps on the engine drop to below 200 degrees.
I went looking for the heater controll valve with no luck.

It does look like some body might have put a new heater core in this van.

research on line so far says this valve is behind the washer over flow bottles in front of the heater core with a vacuum line running to it.
So far i have not located any thing like this yet.
this weekend i plan on pulling the doghouse cover and give the engine a good looking over along with replacing the coolant.
Right now my Early has more heat than this van has.

Thanks in advance for any help in this matter.

......Wookee

Joe there's quite a bit of info about this over at the Astro/Safari site.
http://www.astrosafari.com/viewforum.php?f=34

Catfish, I was at these forums all ready.
I really can not locate this heater controll valve they are talking about.



The water hoses on this Astro run from the block directly into the heater core it's self.

I have a feeling somebody has been in here eliminating things.

I also read that they have eliminated this valve and got better heat.

This vacuum line is also missing along with a vacuum ball.



Things that make you go HHHUUUMMM

.........Wookee

I have to agree with you Joe. Somebody must have removed all those controls. Ack!

That pic looks like the vacuum supply plugged directly into the check valve with no can.
I would suggest making a new canister from an old V8 juice can. (get it? coulda had a V8? )

Oh Catfish you're such a commodian.

commodian

Do the heater hoses get hot to the touch near the heater core? If so, you probably have a air bubble in your heater core. With the way the hoses come in low on the core, it is not hard to get one while swapping the core out.

Unk,honestly I have not checked that yet.
There was also an air bubble mentioned on the Astro forums.
Today as cold as it is here, 30 degrees.the temp gauge went past 210 or so and stayed there.When I drove it the last leg home the temps where in the mid 40's and the temp gauge was at like 150.
There was warm air blowing out of the vents but not hot air.

.........Wookee

Sounds like a bubble. . . They will lodge in the top of the heater core, letting SOME hot water through the bottom, giving warm air at best.

I am going to drain out all of the coolent this weekend and back flush the core inspect the rad.Change out the thermostat.

........Wookee

Up early or staying up late ?

One of those nights.
Went to bed early and woke up in the middle of the night.
a 714 would have done thew trick.......

.......Wookee

Looks like a badly clogged rad is PART of this van problems.
Draining the rest of her internal fluids tomorrow.

.......Wookee

I found some issues while doing some exploratory surgery.
I also found the heater control valve.
when i pulled it the vacuum line came out from the engine with the unit.
I really do not think the vacuum line was hooked up.The control valve does work.
my problem is I can't find the port the line was connected to.

Here is what the area looks like the line came from.



The line is laying where I found it in this picture.
I really need to find this port so i can get this van out of my shop.....

Thanks in advance.....

.......Wookee

I'll try to get some pages scanned tonight from my service manual with the vacuum routing. If memory serves, and keep in mind it betrays me more than not, the supply line plugs into one of the heat actuated vacuum valves that are screwed into the water passage beside the t-stat housing.

Crazy weekend, Sorry I didn't get them scanned, will try again this evening.

Wookie, while you have the dog house off check the cap real good for cracks and arching from the coil which is 2 common problems with these ..also clean the connector wire to the temperature sender real well...they corrode easy and this is the leading cause of Emissions failure as the sender tells the computer its cold so it runs with choke on that in turn plugs the cat...

I had these issues on my 85 and my 98 and bought a 99 for 400.00 dollars because it failed emissions and could not be put on the road...100.00 later, clean pass and sold it for 2500.00 without doing anything else...

I am still at a stand still with this issue.
I pulled up a couple of vacuum diagrams off the net which where NO help at all.
There is NO temp sensors in the stat housing on this engine.

I followed the vacuum line from the back of the switch wich disappeared from site behind the heater.I can only find one vacuum line coming out of the fire wall close to the heater box.

I really need to get this POS back together and get it out of my shop.
I am sorry I bought this thing.
I get it running again there will be a for sale sighn on it.

......Wookee

The temp senders is on the drivers side between the two back plugs if that is a help...There is also a water valve of some sort near the distributor.....can't be much of a help because the heater was the one thing that worked great on both of mine lol


The vacuum lines may be the heater plenum control as well...are the vents opening inside to let the heat in ??

Doc the vents worked.
I just need to find where this vacuum line to the heater control valve goes.
So far I have found a bunch of places it does not go.
It goes to a line that is live when you turn the switch on.
the location of the valve is such a way that the line needs to be hooked up so i can put the rest of the engine together.
IF it was running I could start the engine and listen for the vacuum leak hissing when I turn the switch on.......

.......wookee