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Heater Valve Assembly

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J

JJS

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Hi All,

I'm putting together the heater and the assembly of the heater valve and heater valve adapter to the heater core is baffling. It looks (from the parts manual) like the assembly should be, in order from the heater valve (for BN7):

heater valve
heater valve adapter
o-ring
top of heater box
o-ring
heater core

Shouldn't the first o-ring fit between the heater valve adapter and the heater valve? Or are there two o-rings between the heater valve and heater valve adapter?

Thanks

Joe
 
Hi Joe,

One o-ring only.

There is not an o-ring between the heater top box and the heater valve adaptor, if that is your question. The o-ring goes between the valve adaptor and the valve. See one of my photos, where I show a rubber grommet was used. Close enough to an o-ring, thought the PO.

Heater core
Heater box top
Heater valve adaptor
o-ring
Heater control valve
Heater hose
 
I don't know if I'm adding confusion here or not. I'm with Roger on the location. My heater assembly didn't have an "O" ring per say. It was more like a plumbing seal for a faucet.
 

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Hey guys,

I saw this post from 2008.
I'm having the same problem. I am restoring a 60' BT7 I have assembled it like AUSMHLY did above. What keeps the heater control valve attached to the "intake tube"? Seems like it would just come off over time.

Thanks for any reply.

JB
 
It looks from the parts drawings as if the heater valve, being screwed onto the top of the heater unit box, is then held onto the pipe by the screws which hold the top onto the box. There are two o rings shown, one on the matrix pipe before the top is fitted, and the second between the valve and the box top. I assume when you screw the box top onto the box, it sandwiches and squeezes the two o rings either side to seal the joint.

Can email you a scan of the parts page if it helps. My email address is oui3@orange.fr

Ian
 
I have put it together just like AUSMHLY did above. It all fits well but seems like the heater valve itself should bolt/screw to the top of the heater box. It just "sits" on top of the box when fixed onto the tube. The "o" ring sits between the valve and the valve adaptor. I can see from the parts list that there may be 2 "o" rings but can't see a reasonable place to put the second one. I don't know what the o-ring between the radiator unit and the box top would be sealing. It's a rather odd set-up.

JB
 
Ian, you're close, but not 100% accurate :wink:

When the valve body is tightened to the adapter plate, it compresses the rubber sealer around the tube (as well as between the valve & adapter).

This is considered to be a gland type of seal, and if properly applied, and NOT over tightened, is very effective.

You may still detect some movement of the valve on the tube, but as it is fairly low pressure (about the same as your radiator cap's rating) it will still perform a leak-tight seal.

In my opinion, there should be a slight gap between the adapter and the top of the box; just a little breathing room, to allow for any expansion or contracttion while heating and cooling.
 
thank you for the reply. Your answer is what I had suspected. I wasn't sure if the adaptor itself somehow connected to the top of the heater box to secure the whole valve better. My heater, adaptor and valve were very corroded and it wouldn't have surprised me if a piece had corroded off of the adaptor plate making it impossible to tell. Just don't want to get it all together to find out I was wrong. Another question, any reason why the top plate of the heater box only has one outlet (the other has a metal plate over it)where the "elbow" attaches. Should I take this plate off and have 2 hot air outlets?

thanks again

JB
 
GREAZYFINGERS said:
thank you for the reply. Your answer is what I had suspected. I wasn't sure if the adaptor itself somehow connected to the top of the heater box to secure the whole valve better. My heater, adaptor and valve were very corroded and it wouldn't have surprised me if a piece had corroded off of the adaptor plate making it impossible to tell. Just don't want to get it all together to find out I was wrong. Another question, any reason why the top plate of the heater box only has one outlet (the other has a metal plate over it)where the "elbow" attaches. Should I take this plate off and have 2 hot air outlets?

thanks again

JB
Click to expand...
You want "two hot air outlets"?? You're kidding us...right???
Patrick
 
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