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Heater valve question

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TNMGB

TNMGB

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Yeah, well it finally happened as I've read so many times in other people's posts...big puddle of coolant on the floor. I've crawled up underneath my 79B and looked at everything that would be a problem, checked hoses, etc. and when I cranked him up, then I see the dripping on the distributor cap from the heater valve...yeah, that is a stupid place to put something that has liquid flowing through it. Could be why the Brits are not a nuclear threat.

So what other parts do I need to order so that I can install this? I couldn't quite make out the tiny diagram on Moss's site but I suppose a gasket and is there anything else?

Thanks!
 
Heater valve & gasket (think gasket comes with the one from Moss)...its a bit of a bear to get to the little 3/8" bolts but patience persevears!

Before you order a new one (they're cheap though), go to my website & look at the tech tip for repairing/cleaning them

https://www.theautoist.com/cleaning_heater_valves.htm

Heck, even if you do buy a new one, its a pretty good thing to look at!
 
Since you will probably replace the valve anyway, give the article on Tony's site a look. I found it to be very informative, like most of his site.
 
And consider a swivel socket: 1/4" drive, 7/16".
MUCH easier to R&R the valve with that tool. /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
TNMGB said:
Yeah, well it finally happened as I've read so many times in other people's posts...big puddle of coolant on the floor. I've crawled up underneath my 79B and looked at everything that would be a problem, checked hoses, etc. and when I cranked him up, then I see the dripping on the distributor cap from the heater valve...yeah, that is a stupid place to put something that has liquid flowing through it. Could be why the Brits are not a nuclear threat.

So what other parts do I need to order so that I can install this? I couldn't quite make out the tiny diagram on Moss's site but I suppose a gasket and is there anything else?

Thanks!
Click to expand...

Big puddle of coolant on the floor... That indicates to me that it is more likely that you have a leak at your heater core. Either at the hose fitting, or in the core itself. If the core has a leak near the lower end of it the coolant will drip into the interior of your car, as well as run down the hose to the heater valve. It is less likely for a heater valve leak to run UP the hose and into the cockpit and drip on your floor.

I'd look into the heater box first.
 
Well, if it's the garage floor, and the coolant lines are dry up near the heater box fittings, then I'll have to agree with everyone else /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Thanks for all the input and yes, it is the garage floor I meant. Woo hoo! Another fun project to do...but it doesn't look like it will be too bad (famous last words). Since the old heater valve has been so hard to turn even after coaxing it into somewhat of an operational state, I'll just replace it.
Thanks!
 
replace the cable while you're at it. I had difficulties turning the temp knob on mine too. When I looked closely, I discovered it was because the cable sleeve was frayed and cinched too tight at the valve end. It was impossible to cinch the sleeve any looser without it slipping under normal use. So, I replaced the heater cable with a new one, and only tightened the sleeve cinching crimp just enough to hold it in place. It has been easy as pie to adjust with my bad hand (i'm right handed) ever since.
 
Was that a big deal to replace the cable as well? Just curious before I make things harder, you know.
 
Check cable operation with it disconnected from the valve to tell if it's giving resistance. It can usually be lubed to restore it to normal operation, unless it's been smushed like Rob's was.
 
TNMGB said:
Was that a big deal to replace the cable as well? Just curious before I make things harder, you know.
Click to expand...

If the old one is in good shape and works well, I'd leave it alone. Changing that cable is not a project you do just for fun! JMHO. PJ
 
Unless you're a masochistic contortionist! /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
Oh, I dunno. There are plenty of things that are WAY more difficult to do. I have a 1976 B, and changing that cable was one of the easier things I've done. To make the job as easy as possible, I highly recommend removing the adjustment knob from the dash. I think the most difficult part of swapping the cable for me was cinching the sleeve ends properly, and making sure I didn't over tighten the cable ends. I think I had the cable swapped out in under 60 minutes with normal hand tools.
 
One thing I found on replacing the valve with a new one is, after running the car a few times, re check the two bolts and make sure their snug. Mine loosened slightly and caused a weep at the flange, probably from heat expansion and cooling. I snugged them up a little and they have been good ever since. PJ
 
Is there are replacement part available for the rubber diaphram on the inside?
 
Not that I'm aware of, but I made a mold for them, and Devcon makes a two-part "rubber" I've used in the past. They were Unobtanium for a bit, but now the "usual suppliers" have 'em. I still have a couple older rebuilt ones here as spares.
 
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