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MG MGB Technical - Heater Valve

It seems I have a problem with the heater valve and was thinking about removing it in it's entirety for a while until I can resolve the issue. I am using an aluminum head and the lower bolt is mis-threaded. I wanted to use a blank plate for a time but I am unsure of the type of material I should use to make the blank. Ideas?
Peter Murray

You can use a flat piece of aluminum or steel at least, say, 3/16 inch thick. Cut it to size, drill the holes, bolt it on using a stock heater valve gasket (or just gasket paper) to prevent leakage. Very simple to do.

But. If your problem with the heater valve is that one of the bolts is mis-threaded and you can't securely bolt it on, you won't be able to bolt on the blanking plate any better. Any attempt to bolt on a blanking plate from only one side will result in leakage. Leverage is working against you. Either the plate will bend, or the bolt holding it will.

Resistance is useless. Buy the correct tap and fix the hole.

If the hole is mangled beyond being re-tappable, your options are:
Drill and tap to the next larger size, or
Helicoil, or
Fill the hole (aluminum filler or even JB Weld will work) and then re-drill and re-tap, or
Send head to machine shop and make it someone else's problem
Sam Good

Cut the end of the water valve/tap off
tap in a thread
screw in a hose fitting
go buy an inline cable opperated ball valve such as the RV8's used.
Any reaonalble auto store (or juck yard)
Never leaks , lasts forever,easier to operate, actually lets lots of heat through when you want, and none at all when you don't.
Peter

eg,

http://www.cibolas7.net/12272.html?*session*id*key*=*session*id*val*

I'm now using this valve,(after three failures on the standard rubber diaphragm valve).
this is on a V8, works off standard cable.


Peter Sherman

peter where did that valve come from? Nice instalation I may use it myself. RIC
RIC LLOYD


I went to the local auto shop (east coast auto) and asked an older guy with some experience for an "in line cable operated heater tap". Ovoid the spotty youth, or similarly challenged person, he will just ask you for model and year, so he can look it up on his list. You need someone who knows his stock/inventory.
As you see I got something that looks exactly like the RV8 tap. It could well be one, except it only cost $58 Australian, including tax. Something labeled RV8 would be more expensive I imagine. FYI, the MGB valves cost $65 each.
Packaged by JAYAIR Part No. HA4008
It also has a sticker on it 'Made in Mexico H38C-2211-030 0441-07 '.
It is of the metal casing and plastic Ball valve type (no rubber to perish). It turns very freely. It is rather neatly designed so that you can have it on "low". As ball valve rotates from CLOSED it first has a very narrow (few mm's) slot like opening, which then changes to the full half inch diameter opening. Be aware that it must be fitted the right way around with the cable attachment pointing away from the engine/water supply. Other way around it lets a dribble of water through to the heater. Guess how I found this out!. Right way around it seals/works perfectly, 3 yrs so far. It is a half inch diameter, so you would need to step it down for the MGB heater. I simply greased and pushed the half inch hose over a bit of the MGB hose. Obviously you can get fittings to size change if you want, I think it looks neater the way I did it. At the engine end I did use a size changing brass fitting (same auto shop) screwed directly into the outlet.
Peter Sherman

found clearer picture

Peter Sherman

Although it works in reverse (Knob on closed, valve open) there is an inline plastic valve from late 60's Ford bronco with a V8. $15 at the local Autozone.
John H

I had a leaky diaphragm on my '68 roadster block mounted heater tap. I was damned if I was going to pay $68 for a complete unit when a 50c diaphragm rubber was all it needed. In Kiwi style, I got an old farming gumboot, cut a "diaphragm" out of the side wall of the gumboot, fitted it to the pump with the piston still in, and it has been working for 10 years without a leak!!!
Kiwi Inginuity at work. Cost ? One hour's fun.
R P Shoebridge

One thing to watch out for when using other vehicle's heater valves in the B ~ the majority have input and output nipples that require a larger ID hose than the B heater uses, requiring some sort of step-down adapter. We can use about any valve that will work, but I chose to make my own so that I didn't have to add extra fittings and extra clamps ~ points where other sorts of leaks can occur.
Bob Muenchausen

Inspired by Bob Muenchausen's website, I made the ballcock heater control valve shown here. It was easy and very inexpensive to make, it worked better, and it was not subject to the usual weaknesses toward leaking. Regrettably, I sold the car some time ago and the valve with it. I'm anxious to build another one.

Allen

Allen Bachelder

I did the same as Allen, also inspired by Bob's work.

I do like the in-line valve, though, just for its simplicity.




Rick Stevens

Hope you don't mind, Rick and Allen, but I copied your photos and may add them to those already on my site. I like to show the diversity of work done from my simple basic valve to inspire others to either copy other's work or come up with their own.

The basic ball valve has been trouble free for me now for almost 10 years and tho not as elegant as some, it does present a good opportunity for folks for whom originality is not a consideration. It would be nice if someone would come up with a higher quality unit than many of those OE types currently on the market.

Someday maybe I or someone else will come up with something like the ball valve but within a housing that looks OE. That would be the best of both worlds.
Bob Muenchausen

Rick,

Ah, but yours looks so much better than mine! No excuses, but the one I made was for a car that I just drove (constantly!) for a year or two - then sold before ever restoring it - hence the funky engine bay.

Bob,

I'm honored if you saw fit to use my picture. Just don't put it right next to Rick's! 8^)

Cheers,
Allen
Allen Bachelder

Yeah, well, this is version 4.0 or something like it. A lot of plumbing got wasted before that was finished - and the cable mounting bracket is pure rookie.

Bob, you're welcome to it and thanks. Your site really has been inspirational.



Rick Stevens

This thread was discussed between 04/03/2008 and 15/03/2008

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