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Heater Valve Replacement

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bill_powell

bill_powell

Jedi Trainee
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Happy New Year:

I have a leaky heater control valve. A have never once closed this valve, and so I would like to replace it with a straight fitting.

On the later Minis (1990s w/1275) there is a factory part, #12G2534, as seen here:

https://www.minispares.com/Product.aspx?ty=pb&pid=33696

It is meant for a 5/8" hose, but that's no biggie.

Before ordering one however, I thought I would ask you guys if anyone has changed out their valve, perhaps for a straight pipe fitted to the valve base, and if so what did you use?

Thanks!
 
Some of those valves are easy to rebuild with a couple of o-rings. Have you taken it apart yet?
 
Actually, I'm in the process of re-working the heating system, and the block mounted control valve will soon be redundant and no longer needed. I only just noticed it had a (minor) leak as I was working on things. I thought I might as well just eliminate the valve...
 
$ .50 worth of O rings fixes the leak. Took 5 minutes and you can avoid plumbing changes. Besides that heater core provides additional cooling in the summer.
 
Discussion a while back about putting a cable operated valve that is free standing in the hose. Think it was a Ford valve. I did'nt keep track of it and don't know where to look now but that has merit for me. I like cool air on my legs when its hot, heat when its not and the ability to open it for extra engine cooling when I have too. The water valve on the early cars is quaint but kind of a pain. Mainly good for a conversation starter!

Kurt.
 
In-line heater valve from a '76 Volare is 1/2" and cable operated. Hasn't been available for at least 10 years that I know of but if anyone finds a stash of them I want to buy 2!!
BillM
 
Now you guys are thinking like me.

I'm considering reworking the heating system to make it more efficient and user friendly. Like including a cable operated switch, for instance. And using a bypass line so that the engine coolant flow is not restricted on cylinder #4 when the flow to the heater is closed.

Here's an interesting heater/accessory source:

https://www.t7design.co.uk/index.php?main...3c8555f43965d4a

Just considering possibilities at the moment. My question about the valve really happened by accident; I did not even realize I had a leak (it's really quite minor; oozing, really) until I began thinking about this project, and was looking over the stock system.

If I have a leaky valve, and I'm considering using a different valve anyway, then why not eliminate the leaky valve? They are not even used on other A Series designs anyway. For instance:

Miniheatertapdirectfitting.jpg


This is the factory part I mentioned in my original post, #12G2534, used on Minis after 1990. But it's a little pricey...
 
Sooo... Why not cut a plate and and weld on a bit of pipe? File the plate as flat as possible and use a thick gasket to help it seal.
 
Hey, just mention it on this forum and the possibilitys come up. Thanks. Still think the valve I was thinking of was a Ford valve and was cheaper. I personally never thought the spridgets needed a better heater. I've put a lot of miles on a MGB, they do.
If you need more heat have you tryed a hotter thermostat and covering part of the radiator. If you want to get more elaborate, how about warm air intake to the carbs. That made a world of difference on the 3 Datsun pick ups I wore out.

Kurt.
 
I have also been thinking about replacing the old valve with a cable operated one. While I was doing some work on my TR6 I found that the TR6 valve fits in the same plate that the original Midget valve fits in. Then there is the valve several of us TR6 owners have been installing. As here in Bobby D's web site: https://tr6.danielsonfamily.org/HeaterValve.htm

To operate the valve I found the TR6 cable is plenty long enough to work, in fact it would need to be shortened.

I have not gotten around to doing it in my restoration yet. Wonder what you guys think about it.
 
Tom, That would look nice if you used an adapter to get it mounted solid into the original base.
 
The reason this subject came up with me is twofold:

First, my heating system is long neglected, and needs an overhaul. Worn out fan, leaky box, core really in need of replacement. Also, I really dislike the valve on the heater tap, and the potential for high temps at cylinder #4.

Second, I drive my Midget practically every day, rain, shine, hot, cold. And it's been dang cold here lately. I wouldn't mind a little better placement of air vents, and some control over the fan speed.

Oh...and Tom, I really like that <span style="font-style: italic">easy peasy lemon squeezy</span>. Excellent.
 
Bill: Sounds like what you need is a three way ball valve that will either direct your coolant thru your heater or a bypass line back into y fitting to the water pump. I took a look on the internet but finding a suitable valve will take a while. I'll let you look!!!

Have fun,
Kurt.
 
Look on McMaster-Carr's website. I bet you can find one there.
 
nomad said:
Bill: Sounds like what you need is a three way ball valve that will either direct your coolant thru your heater or a bypass line back into y fitting to the water pump. I took a look on the internet but finding a suitable valve will take a while. I'll let you look!!!

Have fun,
Kurt.
Click to expand...

Kurt, I seem to recall from an earlier conversation that a two way will do. Either it flows through the heater rad or it doesn't, the rest of the cooling system continues to function.
 
JP, Bill also wants to direct more coolant from the back of the head to the cooling system. Most racers do that and quite a lot of street drivers do the same so a 3 way valve would let the coolant bypass the heater core and go right back to the pump. I'd have to read up on exactly what the racers do, I'd think directing it back to a fitting above the thermostat would be best so that it go's directly to the radiator. If you tapped a pipe fitting directly into the thermostat housing and directed the coolant from the 3 way valve to it it would be best.

Kurt.
 
Thanks guys; a three-way valve would be ideal, but as was mentioned finding an appropriate one, much less cable operated, has been elusive.

I was also considering fitting a hose connected directly from the intake manifold line to what is now the heater tap, bypassing the stock setup, and then adding two 'T' fittings to that hose, with two hoses then running to the heater core, with a valve placed on the 'intake' side of the core. Simple enough, but not sure how well it would work.

HeaterSchematic.jpg


HeaterSetup.jpg



EDIT: OOPS...in my diagram, I think the valve might belong between the intake and core side.
 
the problem I see with your diagram is that there is no reason for the water to flow through the heater with the valve open, considering the resistance of the core and the straight path through the T fittings. If you put the valve between the T fittings, you could divert all the flow through the core when closed or a very small effect when open.
 
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