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Leaky heater valve?

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vagt6

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There's water seeping out of the top of my heater control valve, which occurs when I tried to turn the valve to the "off" position to delete the heater summer driving.

It doesn't leak unless it's turned 100% to the off position. I have it turned about 90% off now, which lets some heat into the car but doesn't seem to leak. But when it leaks it's a pretty good stream which gets on the manifold and steams up, not good.

What gives? There's not much to go wrong the valve assembly as I look at the Moss catalog exploded diagram (p. 20). Can it be fixed, or is it time for a new valve, gaskets, etc.???

Anyone have this experience?

Thanks!
 
Not me, I put new packing in the valve stem. Packing from ace.
 
There are a couple different types. Most can be repaired with supplies from your hardware store.
 
Hay Trevor, we both belong to the "we cheep" club.
 
Heater = Auxiliary Cooling Unit for summer (HOT) driving.

YMMV

Steve
 
Heater = not needed in summer if you built the engine correctly.
 
jlaird said:
Not me, I put new packing in the valve stem. Packing from ace.
Click to expand...

Jack, could you elaborate a bit on how to replace "packing" in the valve stem? What's in there, how do you disassemble it?

It seems the valve and peripherals are the same for all spridget models, at least according to Moss catalog.

My leak comes out of the top of the valve stem.

Packing?

Thanks.
 
There is a nut that goes around the stem on mine, loosen and slide up. Put new packing inside and replace.
 

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No, they are not all the same. I have three different versions. One uses packing, the other requires o-rings, and the third I've never had apart.
 
well that is not very helpful. I think the packing one is orginal. Has a small wheel on top. Belongs on BEs for sure.

Ahh, photo above is not Miss Agatha.
 
My bugeye valve leaked and I did like Jack,
got the packing from Ace Hardware, wound it 'round the stem, lightly packed it in, and no more leak.

Ace stock # 4200366 "Graphite Valve Packing Kit"
Self-Forming 3/32" x 24" rope.
In plumbing supply hanging in a bubble pack.

Fred
 
Great suggestions, guys.

So, do you recommend applying the packing to the bottom of the valve, where the wet part is in this photo???

You can see where the water is coming out, at the brass part just below where the knob sits:


[img:center]
Valve.jpg
[/img]
 
Yes, if I am remembering this correctly. you have removed three parts at this point.

1. the wheel handle.

2. the the screw

3 the nut that pushes the packing down into the part where it is wet.

Here is how this works. additional gaskets at the bottom to make the connection for the hose come at the right angle.

The nut right under the handle wheel compressies the packing down around the shaft to seal the fluid in. Not too tight, just enough please.


I hope you have the nut part??
 

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Jack, your valve looks different. As you can see by comparing the photos, yours is taller and has the "nut" part you're talking about. Mine does not, and it isn't indicated in the Moss catalog, either.

Mine's a '74 MK III. Different animal, maybe? Your solution may not work on mine. What do you think?
 
According to the parts list the same heater valve is used from 1958 thru GAN-91407, 1974.

The next valve is an automatic one.

May I suggest you have a peice missing from your valve. See the nut under the wheel on the stem on mine. That nut has a collor that pushes the packing down and makes it tight.

I think you are missing parts.

Has it always been like that or what?? Where is the handle/wheel?
 
Hay, moss is selling em for 29.95, it might be time if you have peices missing.

Or maybe some one on the list has one they would part with.
 
Better photos

Better photos of the problemo:

Here's the valve with the knob and top nut on:

[img:center]
Valveleak001.jpg
[/img]

My finger is pointing to the source of the leak. Could it be internal? Is there an O-ring or something inside that needs replacing???

[img:center]
Valveleak002.jpg
[/img]
 
Re: Better photos

No way for that one to work like mine.

May I suggest that I would remove from car, disassemble and see what makes it work, Has to be a seal in there, Maybe an O ring that goes in from the bottom?

Or or, does that knob push down on the place where it is leaking. Or close fit anyway.

O ring then tighten with knob and nut?

Fit the knob and see if there is room, between knob and the outside valve body for an o ring.
 
Re: Better photos

Hardware store has O rings.
 
Re: Better photos

Will do, Jack. I'll perform heater valve surgery and report back. :thumbsup:
 
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